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TRP quadiem brakes - lever not in place Today I got my new YT Tues bike and I've noticed that front brake lever came off the piston and I have no idea how to get it in place if it is even possible? Is it defective or can I fix it? Rear brake works just fine... <Q> You can see in the first picture that a snap ring is out of place. <S> I’m not familiar with these brakes <S> but I’d have to assume there is something very wrong that must be dealt with by a qualified mechanic or the manufacturer. <S> You don’t want to mess around with brakes, especially on a downhill bike. <S> as <A> It appears that the ball end of the rod should be in the socket with the washer in place, and then the c-shaped snap ring gets snapped into position to hold it all together. <S> That is how it appears to me, however if there are any missing pieces I couldn't say, perhaps an exploded assembly diagram would help. <S> It would appear that the ball has been ripped out of the socket somehow, presumably after the bike was assembled and PDI checked. <S> From the first two photos, the rod also looks a little bent, not an encouraging sign. <S> The best thing for you to do would be to return it to the shop or seller for a repair. <S> YT indicate a 2 year warranty on all components. <S> Depending on where you bought it <S> you'd have a couple of options. <S> If it was from a shop, they should be able to repair the brake under warranty. <S> It wouldn't matter to you; if they do a safe repair, you would have a sound bike afterwards. <S> If you bought it online, contact the seller and contact YT. <S> They might want you to send the bike off somewhere, but it could be more convenient to take it to a local shop to be inspected and repaired. <S> You might be able to ask one of them to contribute to the cost of the repair. <S> Not having to pay to send the bike away would be a good start for you. <S> If you want to attempt the repair or replace the lever yourself <S> that's ok if you fully understand the risks, but <S> if you're here asking the question, it isn't something you've fixed yourself before. <S> Being a new bike, that is liability and risk you don't have to take on yourself, it's what the warranty is for. <A> Here's a parts diagram for the lever from TRPs website for this part <S> In your pictures we can see part number 4 and the shaded out lock ring and washer to the right of part number 4. <S> There is a set of parts that are in number 7. <S> In your pictures I don't see the left most cone shaped washer. <S> It looks like a part might be missing. <S> On their website the part numbers have names. <S> Part number 4 is the "detented pushrod" <S> Part number 7 is the "master cylinder piston" Knowing the names might help in your conversation with YT.
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As it’s a new bike, take it straight back to where you purchased it and get it fixed or replaced under warranty. Maybe they can repair the lever after an inspection in person, or maybe they would need to swap the lever for a new one.
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How to remove hex crank bolt I have been looking online for tutorials on replacing a chainring (or three) for my Scott mountain bike: https://www.thebikelist.co.uk/scott/aspect-40-2012 When trying to take off the chainset so that I can remove a chainring to replace it, the crank bolt holding the chainset on looks different to most of the tutorials I've been watching online. I am wondering what tools and what procedure I would require to remove this so that I can replace my chainset. The bolt is a hex bolt which has 'CH 12.9' printed on it. Here are some photos: <Q> A 13 mm (or possibly a 15 mm) <S> socket should do the trick for removal. <S> You won't be able to budge the crank arms after removal of these. <S> For this you'll need a Crank puller. <S> One aspect of this tool threads into the center of the crank arms (not the same spot as the fastener you just removed but right around there). <S> Then a second bolt tool with a special head threads into the first part, pushes on the spindle of the bottom bracket which affects the movement of the crankarm off the spindle. <S> Here's a link to a Crank puller <S> .Here's a couple "for instance" chainsets that are around the level of your current one: Shimano Tourney , SRAM <S> Should you choose to remove and change your bottom bracket, which the specs for your bike state is a Shimano cartridge-type BB-UN26, you will need a bottom-bracket tool . <S> Cartridge bottom brackets last a long time, so it's likely you don't necessarily have to change it as long a the spindle is in good shape and there doesn't appear to be any grinding or roughness when you spin the cranks (with the chain off <S> is best as you get a better feel for the status of the bearings without the noise and vibration of the chain).One aspect to think about, is if you choose to remove your old bottom bracket, that will open up your options as far as cranksets go. <S> Now days, the bearings are external to the bottom bracket shell, are far lighter than cartridge bearing BB's, and the cranksets are two piece: the right arm with it's chainwheels also has a spindle attached which the left arm slips on to and connects the system together. <S> While they sell and advise the use of special tools for these bottom brackets and an aspect of the crank, one can get by with more common tools used with good sense <A> The ‘CH 12.9’ hex bolt just needs removing with a hex socket, try a 14mm first. <S> The bolt on both sides is right-hand threaded so perfectly normal. <S> It is a hex socket instead of an Allen key fitting, but is doing the same job. <S> When it is removed you will likely see the square outline of a square taper B.B. spindle, or else be able to identify the spindle type from the tutorial you are following. <S> You then need the cotterless crank puller tool to suit <S> and away you go with the tutorial for pulling the crank. <A> There’s a bit of a terminology confusion here. <S> To replace the chainrings, or replace the crank, you don’t need to take the bottom bracket out if the frame. <S> (The bottom bracket is the set of bearings the crank spindle runs in), You have a ‘3-piece’ crank where both the crank arms are separate from the spindle and the spindle is integral to the bottom bracket, so you just need to pull the cranks off. <S> Some spindles have a hole in the end into which a crank bolt threads, others have a threaded extension onto which a nut threads. <S> Some crank bolts have an Allen key fitting, some have a head for a hex socket - you have the latter. <S> The link you provided to the specs of the bike imply the crank is Shimano Tourney, or another low end model. <S> Often these don’t have removable chain rings so you’d have to replace the entire crankset <S> if this is the case with your crank.
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The bolt on the end of the spindle needs to be removed and the cranks pulled off with a special crank puller tool.
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How can I offer a test ride while selling a bike? I am selling a bike to someone I don't know from Craigslist. I expect that the prospective purchaser will want to test ride the bike before making the purchase. How can I prevent them from riding away with my bike during a test ride? <Q> The simplest answers are ask for their ID, or for their car keys if they arrive by car. <S> There are plenty of other options on various forums like https://www.bikeforums.net/general-cycling-discussion/446194-selling-bike-craigslist-test-rides.html https://www.bikeforums.net/general-cycling-discussion/687171-how-do-you-let-potential-buyer-test-ride-your-bike.html <A> Cash in hand. <S> They give you the purchase price, in cash, and it sits in your pocket while they do the test ride. <A> If you can't do that, then I'd suggest you have the person test riding <S> give you something valuable to them <S> so they come back to claim it. <A> Go to a Skatepark, usually there you have access limited by one or two doors, they are usually free, it's a good place to test a whip, you have mostly good visibility and riders, and depending on your location it may even have guards. <S> In this kind of eviroments if you shout "thief" or "help" skaters and bikers will help in my experience, they like their skate parks to have a good rep <S> and they tend to push away sketchy people, altough YMMV. <A> I've just sold a bike. <S> The buyer left their bike locked to the fence next to myself place. <S> I offered to test ride as long and far as they consider necessary. <S> If they wouldn't have turned up I should have waited there until they recovered their bike. <S> If that would have taken unusually long I should have put my own lock at their bike and inform them via email or text message. <A> A lot of people are saying to take the ID, but isn't checking the ID sufficient? <S> Besides, there are other things, like a bank statement, which confirm the name and on top of that their address. <S> I guess if you live close to the buyer you could ask to meet them at theirs. <S> You see them leaving their house, how exactly are they going to hide from you? <S> Another idea is to pick a good spot. <S> A tennis court for example would be naturally closed off, stand next to the only gate and voila, they'd have to use force to get away with the bike. <S> Also, sometimes just the good-old first impression is sufficient. <S> You can base the decision of whether you will let them try it out on that.
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If you have another bike that you are not selling, you can ride next to the person test riding the bike to make sure they don't take off with it.
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Replacing multiple spokes (9/36): more like replacing spokes or rebuilding a wheel? I've never built a wheel and while I'd like to learn one day I'm not going to learn on this one. On Saturday my rear wheel ate my derailleur (and bent the steel hanger in the process)*. No spokes broke at the time. After straightening the hanger I fitted the RD of my MTB (both are Shimano 9 speed) and it worked quite well. After about 130 km I heard a ping, and shortly afterwards the broken spoke snagged the chain and I came to a sudden stop. 20 km gently home and I go to change the spoke (it's a tourer, came with 3 spares). When I get the cassette off I find another has gone, and all 9 of those that come outwards on the drive side are damaged. So clearly 9 spokes need replacing. Is it reasonable to buy 9 new spokes and lace them in and tension them one by one then true the wheel? Or is that a stupid idea? I've got time to spend on the former approach as getting the wheel to a shop is a considerable hassle. * there are some pictures on Strava for anyone who's interested in that bit. <Q> In your case, spokes broke because they were damaged. <S> The other spokes are presumably not weakened, so you can just replace the damaged ones. <S> Of course, if the wheel has a lot of miles on it you may elect to rebuild. <A> The wheels got two missing spokes already - its not true now. <S> I'd fit the replacement spokes, add a tape flag <S> so you know which ones are new, and roughly tension. <S> Then replace any damaged spokes that look iffy. <S> Do the worst ones, and keep replacing until you feel the remaining damage is more cosmetic, or till you run out of spare spokes. <S> All spokes is probably a bit drastic, but all on one side is your upper bound, at $2ish each its still $40iish of spokes. <S> Then once all the damage is removed/mitigated work through the process of truing, or get a LBS to do it. <S> I see its a disk brake, so runout doesn't have to be approaching zero <S> :) <S> Do shout yourself a good (park or pedro) <S> spoke key if you don't have one. <A> The wheel is repairable and it's a bad but not uncommon incident. <S> Only a very cheap wheel is worth replacing completely in this instance - I get that it's only a 9-speed, <S> but I also see a disc brake in there. <S> Spoke replacement one by one is the way to go. <S> Not long to do, but all in all it might take up to half a day to true the wheel. <S> The spokes themselves should cost about a quarter each, give or take.
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If a wheel starts breaking spokes, the general advice is to have the wheel rebuilt with all new spokes, because all the spokes are likely weakened by fatigue and will keep breaking. A wheel rebuild should cost around $50 at a LBS.
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How do I get a cleat that's stuck in a pedal, detached from the shoe, out? While out riding on my XC bike today, I encountered an issue with my cleat: The connector between the cleat and the shoe - the part that you screw into - died, and I lost a screw. So I had the shoe attached to the pedal, unable to unclip - because I was able to completely turn the shoe around without the cleat detaching. (The other cleat still worked, and I noticed that I couldn't unclip in a safe enough situation that I avoided biting the dust.) When I got home, I detached the shoe my turning it around enough times that it unscrewed. (Trying to tighten it by screwing it the other way didn't work.) Unfortunately, now the shoe is detached, leaving the cleat itself still inside the pedal, with a single screw sticking out: How do I get the cleat loose? <Q> Your goal is to apply torque to the cleat as you would with your foot in a shoe. <S> So essentially you need something like a gigantic flat screwdriver. <S> I have a mini crowbar that would do the job, for example, but if you have any metal tyre levers they might be big enough. <S> Slacken off any tension adjusting screw first <A> Grip the cleat and turn it either clock-wise or anti-clock-wise <S> Mind fingers and eyes, though! <S> It might be a good idea for both methods to reduce the spring tension of the pedal by turning the adjustment screw as far to the '-' sign as possible with a hex key. <A> Other answers are good, but I'll add these possible options if you're short of the tools they require: <S> Use an appropriately sized punch or drift and tap the cleat out witha hammer. <S> Hit the back but from the side, you need to be pretty handy but a quick blow in just the right spot should do it. <S> If you can't figure out what Imean, then it's best you don't try it. <S> Unscrew the Phillip's CSK screws and see whathappens. <S> As the cleat is under compression, the front bit might popoff with a wee bit of gusto at some point. <S> If yousee any coloured residue on the threads of those screws afterwardsthat is some kind of threadlock, best apply the same when youreinstall them. <S> An amount of lubricant around the rear of the cleat would likely help in most of these discussed cases.
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Alternatively a medium sized screwdriver used as a lever at the rear 'nose' of the cleat will pop it out. Use water-pump-pliers or locking pliers (vise-grip).
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Maximum weight of a pedal vehicle I can't seem to find a straight (approximate) answer to this question. What is the maximum weight of a pedal vehicle (cargo bike, rickshaw etc) an average person can drive at a decent speed, say 15-20 km/h? <Q> How quickly a person can move load of that weight will depend on his or her physical condition. <S> Someone in reasonable physical condition can generally pull a 300 lb load at 10 mph (16 km/hr) on level ground if there's no wind. <S> A person exerting the same effort could pull a load of 600 lb. <S> (275 kg) at a speed of about 8 mph (11-13 km/hr), and a 1000 lb load at about 6 mph. <S> At the page linked above there is a calculator: to estimate how much weight a typical healthy individual could transport on a warm day in still air using a bike and trailer or cargo trike. <S> Things like wind speed, equipment condition, and personal health can have an enormous impact on results, so use this only for rough approximations. <S> Bikes At Work is talking about a bike pulling a cargo trailer but the information can be extended to other pedaled vehicles. <S> Once you get a weight moving on the flat you can move a lot of weight - given the right gearing given a reasonable level of fitness. <S> Hills are a whole other world. <A> You question is difficult to answer directly because bike and rider mass isn't a major factor that determines velocity for a given rider power output. <S> A rider exerts force on the pedals which translates into a force that moves the bike forward. <S> At a constant speed the forward motion is opposed by aerodynamic drag, all the friction in drivetrain components and the rolling resistance of the tires. <S> The limiting factors would actually be the acceleration a rider could achieve or the maximum slope they could ride up at a given speed. <S> In these cases rider output power and total mass directly determine the answer. <A> First we need to agree on the power we are willing to contribute. <S> A trained cyclist may produce 400 W that is already not easy. <S> Then the load is limited by the hill gradient we want to be able to overcome at the reasonable speed (4 km/h I think). <S> As power = speed * force, 400 W means we can have 400 N at 1 m/s (3.6 km/h, reasonable). <S> If the gradient is say 5 degrees (a serious but manageable gradient for a train), 400 N / sin(5 degrees) = <S> 4590 <S> N = <S> 459 kg. <S> This includes also the weight of the bicycle and the cyclist, not just the payload. <S> Another limit is the acceleration. <S> We probably want to reach that 1 m/s in 1 second or about, otherwise it is difficult to stay standing. <S> This means moving with 1 m/s^2 acceleration. <S> As the force is acceleration by mass, our 400 N can provide the wanted acceleration for 400 kg that is about just right. <S> Of course, something like a third wheel would allow longer time for acceleration. <S> Hence it looks like about 300 kg could be transported. <S> For such a load, the friction may not significantly increase with the mass, a big part of the friction comes from the air. <S> While 400 W are not easy to produce for longer, we would only need that much uphill and for starting, so overall may be doable. <S> This payload is also consistent with capacity of the cycle rickshaw bike that is usually built for the two passengers at most. <S> For a less trained person seeking a comfortable ride, I would reduce the power requirement to 200 W or about. <S> This means that about 200 kg of the total mass, or 100 kg of the payload should be possible.
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Aerodynamic drag and rolling resistance only depend in part on mass (heavier bike is bigger, bigger tires have more resistance). According to Bikes At Work : Our experience has been that most people can comfortably pull 300 lbs (137 kg) with a typical mountain bike and cargo trailer or cargo trike.
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How to create a bicycle that rolls backwards when you pedal forward? This may seem like a crazy question, but I am currently trying to design a kinetic machine where pilots are facing away from the direction of motion, adding whimsy and curiosity. As someone who doesn’t have a lot of experience with redesigning bicycles, I am struggling with coming up with a functional design where the gears of the bicycle could still be changed. The first idea I had was to arrange the chain in a figure eight shape, making the back wheel of the bike turn backwards while still pedalling forward. Although I haven’t prototyped this design, something tells me that having the chain cross like that would create too much resistance to reliably change gears. Another idea is to add an extra gear between the pedals and the chain, changing the direction the chain is going entirely. However, I’m not sure if the size of said gear would interfere with gear ratios on the bike? If anyone is interested in helping me out, I would greatly appreciate it! <Q> I refer to a bike throughout, though I suspect you're actually going for something with more than two wheels, and likely more than one rider. <S> Multi speed bike gear systems generally can't be driven backwards. <S> This means that if you really want gears, the chain that drives the rear cassette or hub gears must move forwards. <S> Fixed gears are designed to be driven backwards for braking. <S> If you really want a range of gears the best thing would probably be to install a geared hub the wrong way round. <S> This would need a left side chain, but you should be able to achieve that with tandem or BMX components (tandem parts are more likely to be compatible with other types of bike). <S> This approach would leave the bike as effectively a front wheel drive, rear steer machine, which would be very unstable. <S> You might be better off driving the bike as normal (rear wheel drive, front steering) and turning the rider round. <S> This would be (conceptually) as simple as clamping a saddle onto the top tube and putting your figure of eight chain in place as above, but would work with normal derailleur gears as the chain would be pulling correctly. <S> A single chainring and a couple of idler sprockets with guides would be a good idea to maintain reasonable angles in the vertical plane. <S> For a little inspiration you might want to read up on the retro direct drive. <S> This had one gear ratio pedalling normally and another driven (still forwards) by back pedalling, and the bike could still freewheel fowards. <S> Your point about intermediate gears is easily dealt with by making both gears on any intermediate axle the same size. <A> Taking a hint from some recumbents that have weird gearing, you could get a couple of plastic tubes, run the chain through them, then twist one against the other, so that the chain is in a figure 8, similar to what you suggested. <S> You'd need a long chainline, and probably fixed gears vs derailers. <A> Going with some recumbent designs, have your drive train as usual with a bike but instead of driving a wheel you drive a cogwheel, from which you can drive your wheel or whatever you used to drive your 'bike'. <S> Do you know about the Human Powered Vehicle Association? <S> http://www.whpva.org/hpv.html <S> They have many more vehicles than I did see in the site. <S> Some of them are back to back tandem recumbent cycles, where one of the riders sits back to the drive direction. <S> For those they have to worked out how to switch the direction of leg movements compared to direction of travel. <S> (Link to a drawing of one of those tandems.)
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You could easily choose to go for fixed gears on a machine like this, in which case your figure of eight chain would work, but you'd want a chain tensioner with guides in the slack side, so the chain doesn't touch itself at the cross.
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Help identifying make of steel elevated chain stay mountain bike frame Could anyone tell me what is the make or model of this bike there are no visible numbers or name except for this sticker of the maker of the seat tube. I appreciate all the help. you guys know your stuff. <Q> Roadmaster Techno Trac. <S> Sears never made bikes, they bought them from other companies like Steyr, AMF-Roadmaster and Murray. <S> see one here with the original decals still intact (and a broken frame) https://www.flickr.com/photos/rickpaulos/49958454372/ <A> Sears F.S. (Free Spirit) Elite. <S> Came in Teal or Blue. <S> Made out of high tensile steel. <S> So heavy <S> it feels like it was made from lead and pig iron. <S> Came with cheap parts. <S> Made at a time when everyone and their brother was climbing aboard the e-stay bandwagon in the early nineties. <S> I've only seen a few of them, and all were 19" frames. <S> I have one in storage. <A> As pointed in many threads on this site, (for example this one: <S> Why shouldn't I care what model/make/year my bicycle is? ), it is rarely necessary to know the exact make and model of your bike, unless if happens to be something so special that it has high collector value. <S> What might you need to know about this frame? <S> 1) <S> the material: Conveniently provided by the sticker. <S> 2) what components will it take? <S> Based on the design, it was almost certainly produced between 1989 and about 1995 (when steel elevated chainstays frames were briefly popular and a ton of different companies made them). <S> It's a mountain bike that is intended to take 26 in wheels and post-mounted brakes, such as cantilevers or v-brakes. <S> The bottom bracket shell is very likely to be a standard threaded, 68 mm wide. <S> This will accept a wide variety of bottom brackets, so you can set it up with just about any type of crank you want. <S> The fork is threaded, so you will need to use a quill stem or a quill adaptor. <S> The rear dropouts are probably 130mm (this can easily be measured to check), so using modern 8-10 spd rear wheels (with 135 mm width) will require spreading them a bit. <S> Older 7-speed rear wheels should fit. <S> The bent seat tube is an easy to spot feature, as is the ovalization of the down tube where it meets the head tube. <S> Also the U-shape of the chainstays and seatstays and the lack of any extra cross pieces in the rear triangle. <S> Whether you find it is just a matter of luck, as so many different frames of this style were made that you'll only find images of a small fraction of them. <A>
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If for some reason you still really want to know the exact make and model, you can sift through pictures online of this style of bike (search something like "90s elevated chainstay mountain bikes") and compare the frame designs. It’s a road master techno trac Based on the frame material and design of your bike, it is clear that it is a decent, but fairly generic frame, so it is extremely unlikely to be of high value.
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What can cause the front wheel to lock up when going over a small bump? I was going over a bump. When the front wheel hit the bump, it suddenly stopped moving, the rear wheel lifted off the ground, and I was thrown face-first onto the road. I sustained injuries to the face, hands, chest and knees, and had to go to emergency (see edit 2 for photograph of injuries). I'm fine now, but I wanted to understand this so that I can be safe next time. This happened with two different cycles, so I know it's not a defect specific to a unit or to a model. One was an e-bike, with small wheels (maybe a foot in diameter), poor or no suspension, and was going at its maximum speed of 25kph. Since I was asked, here's a photo of my riding posture: The brake: And the brake lever: (These were taken on another unit of the same model, but they're identical AFAIK.) The other cycle has the usual-sized wheels, no suspension, and was going at 25kph or slightly slower. In both cases: I was going more or less straight. The road was dry. I never pressed either brake. The bump was tiny, half a cm at most, and the bike can navigate much bigger bumps at full speed safely. The road was otherwise smooth. It was the front wheel that caught the bump. I was thrown over the handlebars. There was no indication of anything going wrong before I was thrown over the handlebars — no skidding, no scraping sound, no loss of balance, nothing. The vehicle didn't have apparent damage either before or after the incident. I wasn't carrying any loads. I didn't have loose clothing that can get stuck somewhere. I wasn't applying the brakes. Is it because the bump caused the front brake to apply spontaneously? Is there anything I can do to be safe, because at this point, I'm a little concerned about using bicycles or e-bikes any more. <Q> If you have quick-release or bolt-up front axle that is not properly tightened, then going over a bump could cause it to come out of the fork dropouts. <S> Normally dropouts are equipped with lawyer tabs to prevent this, but they aren't 100% effective or your bike may not even have them. <S> Once it drops out of the dropout, the fork would then no longer be supported and would drop onto the tyre brining it to an abrupt stop, likely catapulting the rider over the bars. <A> This is inexplicable and we're missing some details. <S> Any modern bike tyre will be 20mm wide as a bare minimum. <S> Your electric scooter appears to have approximately 2" or 50mm tyres from the photos. <S> As such a 5 mm bump will be no more than a quarter of the tyre - its not even going to snake-bite at normal pressures. <S> At 10% the height of the scooter's tyre it shouldn't even be noticeable. <S> Here's my guesses and why The rental bike was poorly maintained <S> and there's something significantly wrong with it. <S> The electric brake "suffered an uncommanded activation" - that is it came on without your input <S> (less likely - would have been a big skid not an OTB) <S> This would have broken/dented/bent spokes and probably put a mark on the fork. <S> Something you're carrying caught a spoke unnoticed. <S> Something you're carrying wedged in between a wheel and the frame, or a wheel and the brake. <S> Something was across the road that you didn't see - a trip wire. <S> The hole was much deeper than you realised? <S> Perhaps measure it. <S> All in all I feel there's some assumed knowledge that we're missing, hence the request for photos. <S> I'm not doubting you, just there's something unstated. <S> Given <S> This is a fascinating question - please add more info and we'll see where it goes. <A> Something getting stuck between the spokes <S> It's feasible that some foreign object gets in between the spokes and locks the wheel on contact with the fork. <S> It can be a stick laying on the road, but given that OP hasn't noticed it it could be something hanging on the bike, maybe there's some accessory you used on both bikes when the accidents happened? <A> If both bikes can / have navigated bigger bumps without issue then I'd suspect that the 'half a centimeter' bump wasn't the cause of you being thrown off the bike, that it just happened to be there on the road where you fell off. <S> If these both happened at the same point in the road I'd be more suspicious about it being the large scale road geometry rather than the small scale road geometry of the bump. <S> Maybe the surface has a longish hump followed by a dip, such that it pushes the front of the bike up (several inches) and then a bike length later drops the front wheel into a dip while pushing the back wheel up... <S> the effect would be to tip you forward as the handle bars dropped and the saddle kicked up under you. <S> If you're way forward on the bike or you ride a short framed bike that might be enough to tip you off. <S> I know from experience that some un-flat road surfaces have kicked me up on the saddle... and have dropped the bars out from under my hands... <S> and I've learned to ride over that sort of terrain with my weight not fully on the saddle letting the bike buck around underneath me and using legs as suspension. <S> With poor road maintenance where I live I'm regularly riding routes with bumps much bigger than half a centimeter on 23mm racing tyres running at 90+ psi. <S> As to why no-one else notices it? <S> maybe they aren't travelling as fast. <S> Maybe they ride in a different geometry. <S> Try riding that part of the journey much slower, you should (1) not get thrown off and (2) have more time to feel the sequence of movements of the bike under you. <S> Photos of the road surface may help give a clue. <A> Since there's not much detail provided about the physical surroundings of the crash <S> (i.e. no pictures of the road surface or the bump you hit), we're all really stabbing in the dark here. <S> I'll continue that trend... <S> Looking at the front brake of the bike, it appears to be cable actuated and the cable pulls back on that brass arm. <S> If your front tire passed just to the right of said object, the object could impact that arm from the front causing the front brake to suddenly engage. <S> I.e. in your second picture: <S> Such an object would only have to be a few inches tall, one of the risks to such a small wheel with so much of the brake mechanics exposed like that. <S> After flying through the air, being injured, dazed, etc., it would be easy to not notice the object, which may also have been tossed out of the way by the impact.
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Complete and unexpected failure of a bearing would jerk the bike suddenly. Some other rider shoved an obstruction into your wheel unnoticed, or a stick lodged into your wheel unnoticed. Suppose there was a small hard object in the road that you didn't notice, e.g. a dusty rock or piece of wood that could easily blend into the road surface and be missed at your acknowledged speed of 25kph. there's two different bikes, with similar reactions, I am wondering if the common factor is the rider, your technique, your clothing, your shoes, or even something you're not aware of, like your physical ratios, or your bone structure affecting posture leading to something.
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Fixing leg position while turning I've recently landed on asphalt because I've met the ground with the left pedal when turning left... It was painful, but no visible damage to me or bike... The problem is, that my natural position when not pedaling is with left leg down, every other position (right leg down, or middle position) are in long perspective exhausting for my muscles... I don't know if it has to do with some asymmetry in my pelvis or false muscle memory/training (I rarely stand in upright position as well). Are there any exercises targeted at muscles responsible for good position while riding? When I try this while riding, it's quite exhausting and often makes me making dangerous errors, so I hope there's some exercise I could do at home. <Q> Assuming you don't have fixed gears, i.e. the wheel can roll forwards without the pedals turning, the best way to corner is with the outside foot down, and weight on that foot. <S> The thing is that you don't have to hold this (outside foot down) position for more than a few seconds per corner. <S> If you can pedal without trouble you should be able to hold it briefly without trouble. <S> I suspect that your comfortable coasting position is mostly a learned habit <S> - I know that I habitually unweight the saddle for bumpy descents with my right foot back, for example, and don't even notice for a few minutes. <S> A conscious effort to hold a more appropriate position is worth trying before anything else - that would be a useful start even if you do find you have to do something else. <A> I'm not trying to be snarky or condescending so please don't take it that way. <S> Proper pedal position for whatever maneuver you're performing is one of the fine points of learning how to ride. <S> I'm 60 <S> + and expect to be learning as long as I'm still breathing. <S> Don't expect it to be quick or easy. <A> I'm going to make this an answer because I believe it is the only truly correct answer we can give you. <S> Do not ask the Internet at large for medical advice! <S> As you yourself note, there could be a number of different causes; I can think of a couple more you didn't list. <S> Some of those are biomechanical, and you definitely need to see someone in that case. <S> Doing the wrong exercises can cause injury if you have a biomechanical issue you're not dealing with. <S> Ask other cyclists for recommendations for a good physiotherapist. <S> In my experience they're a good first point of contact; they can do a lot for you, but they can also make qualified referrals if they can't help. <S> And unlike a chiro, they're pretty good at knowing what they can't do. <S> (If you're dead set on dealing with it on your own, go to YouTube and look up unilateral leg exercises; it's on you to pick the right ones and do them properly.)
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If a sports medicine specialist can't find any underlying condition that could be giving you trouble, you need to develop some new habits. And actually if you're cornering at modest speeds you can hold your pedals with the cranks horizontal and avoid the ground. Changing a long held habit is one of the most difficult things a human can do.
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Is there a way to calculate the correct bicycle tire pressure? I have 57-559 (57 mm width, 559 mm diameter) / 26"x2.125" tires.I weigh about 95 kg / 210 lbs.The tire's sidewall shows a single pressure value of 300 kPa / 43 psi. However, this calculator shows that given a fixed tire size, different rider + bike weights would have different optimal tire pressures. Is there a way to calculate such an optimal pressure? <Q> I looked into it and found this PDF: 2004, Berto: "All About Tire Inflation" ,where the optimal tire pressures were found experimentally from a Tire Drop test, where Tire Drop is the distance that the tire sags under the weight of the rider and the bike. <S> For a given tire size and load, the optimum inflation pressure for comfort and rolling resistance produces a Tire Drop of about 15% of W (the Section Width) or about 20% of H (the height from the ground to the rim). <S> For my case, that document shows the minimum tire pressure somewhere around 25 psi / <S> 172 kPa for a 26"x2.125" tire. <A> The desired tire pressure depends on where do you want to ride, and to a reasonable extent on what you "feel" - which might be different than what a different person of your same size/weight feels. <S> What you can do is find a "recommended" tire pressure and work from there. <S> In time tire pressure drops, at some time you will find the pressure too low - measure it and remember it as your "minimal" tire pressure. <S> Try with higher pressure than recommended and "feel the ride" - MTB tires with an extreme thread pattern at high pressure rumble very much on asphalt, a lower pressure "mellows" the ride (vibration into the hands). <A> There is no such thing as optimal tyre pressure. <S> Tyre pressure is always a compromise between comfort, rolling resistance, grip and likelihood of puncturing. <S> This depends not only on tyre dimensions and rider/bike weight but also on the terrain you're riding on and the weather. <A> Most tires are labeled by the manufacturer with maximum load - inflation numbers. <S> These depend on the design, materials and construction of the tire as much or more so than its dimensions. <S> While a manufacturer may be able to provide optimum inflation info I don't see any way to develop a calculator that would do more than give you a wild guess. <A> Even if by "optimal" we mean something specific and measurable like "least rolling resistance", there is no such pressure. <S> Minimum rolling resistance depends on the surface. <S> On a smooth surface, like a varnished wooden velodrome track, high pressure is best: the higher the better, with diminishing returns. <S> On a bumpy surface, there is an optimal pressure with negative returns if it is changed either way. <S> (And note, by the way, that an off-road tire with "knobs" constitutes a bumpy surface, even if ridden on a smooth surface.) <S> The pressure depends on how big the bumps are, and the load on the wheel as well as suspension details. <S> Practically speaking, it can only be experimentally determined; and for that to be valid, we actually need a way to measure the rolling resistance of that specific equipment on that specific surface.
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You can have an "optimum" tire pressure - unfortunately, when riding on road you want higher pressure, when riding on low grip surfaces you want lower pressure (more tire in contact with the ground), when riding on very uneven terrain you want again higher pressure to prevent flats, when jumping you want higher pressures, and so on and so on.
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Should I avoid hard-packed crusher dust trails with my hybrid? I ride a Trek FX 7.2 , with 35mm Bontrager hard-case lite hybrid tires . I'm still fairly new and inexperienced with cycling, and I've driven exclusively on roads so far. I'm looking to start increasing my distance and speed, with the goal being to be able to perform a 50K ride by the end of summer (my longest ride so far was 25k). To this end, I've started looking for new routes to go cycling on. One route I've found that seems like a great choice is the Rum Runners Trail , which is part of a much larger trail system going across the entire province. Most of the trail is made up of hard-packed crusher dust , which I believe looks like this: The website above says it's a great surface for hybrid bicycles like mine, but the product page for my tires makes me concerned this isn't the case. Specifically, there's this answer from a Trek employee at the bottom of the page: The H2 tires are going to be designed for pavement riding and not really for gravel riding So essentially right now, I'm not really sure if I should be riding on this trail with my hybrid. I've considered just going on the trail and finding out first hand, but I'm still fairly new to cycling, so I'm worried about damaging the bike (or myself!) due to driving on terrain the bike isn't made for. Is my bicycle a good choice for this hard-packed crusher dust trail? The H2 aren't what the bike shipped with. I bought the H2 late last year, after the original tires got a flat. <Q> You are absolutely fine riding the Trek FX 7.2 with the Bontrager tires on that trail. <S> That gravel surface is not any worse than rough, worn tarmac so go ahead and enjoy those trails. <S> You don't really need much tire tread (or any) on flat crushed gravel trails, 35mm wide tires have plenty of volume. <S> Be aware that you will have less grip, both in cornering and braking. <S> Try running slightly lower pressure than you would on the road. <S> Avoid big bumps and potholes. <S> Carry a spare tube, tire levers and CO 2 inflator or mini pump in case you get a flat. <A> For that trail you've got a very suitable combination of bike and tyres. <S> I'd happily ride all day that on my 32mm marathon supremes, which are more of a road tyre than you've got. <S> We have a similar surface on parts of a local trail ; some riders will happily ride 25mm slicks on that but others are less happy on 28mm or smaller. <S> Looser gravel is OK for shorter distances on 32-35mm <S> so don't worry unduly if you encounter a bad patch. <S> If any has degraded to the point of being muddy take it gently and avoid sharp steering; the same applies if the surface has been recently repaired and there's some loose mnaterial on the surface. <A> There are three factors to consider with gravel roads: <S> Smoothness of surface <S> A gravel road that's been abused by cars for a while develops first small, regular ripples. <S> These are a PITA to ride on without suspension, as the ripples tend to be hard to avoid, and hard to see in the first place. <S> After those ripples form, some of them develop into veritable potholes. <S> A single, shallow pothole can generally be ridden through if you flex your muscles in time, but deep ones need to be avoided as they can be quite hard on the material. <S> Especially without suspension. <S> A newly built or refurbished gravel road does not have either problem, and may be significantly smoother than a shoddy, old, little-used pavement road. <S> Softness of surface <S> Pavement does not give in a bit when a bike's tire rolls over it. <S> Gravel does. <S> A tiny bit. <S> Some of the grains of dirt get dislodged, and the energy for that movement comes from you. <S> Many gravel roads are quite good at this point, even though you may find that your speed does drop a bit on the gravel road due to this effect. <S> However, some gravel roads lack the components that lock the grains of dirt in place, so your tires dig deep, visible trail, which drains a lot of energy. <S> Punctures Gravel roads consist of many, many little stones. <S> Some of them round and smooth, some of them rather pointy. <S> (I don't want to ride any road without puncture proof tires, as a matter of fact.) <S> But I do avoid bad ones. <S> Both the ones that are too soft, and the ones that are too rough. <S> It only becomes impossible to ride a road when the road becomes so soft that it's basically deep, unbound sand. <S> Such surfaces can drain more power than I'm able to put out. <S> Roughness, on the other hand, is never a factor that forces me to dismount. <S> It forces me to slow down, to navigate the potholes one by one, but it's still "ridable". <A> Just posting an answer to confirm that I've now gone on this trail multiple times, and my bike has handled it perfectly fine. <S> It's not quite as good as pavement, but the difference is small. <S> I also took a picture of the trail itself to help other others wondering about similiar trails (the one from question is from the trail website):
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You don't want to be riding gravel roads without puncture proof tires. From my experience with puncture proof 32mm tires: I can ride on pretty much any gravel road.
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How to recognize a bad tire? The most expensive "consumable" while operating a bicycle would probably be tires. Enthusiasts endlessly debate the relative merits of different sizes, profiles, tread patterns,inflation pressures and just about anything else that might help define the best tire. I use my bike for primary transportation and moderate cardio averaging 15K - 20K daily. The terrain is fairly level but the traffic is dense and the road surface varies from virgin concrete to "what road?". For the time being I'm still running 27 X 1 3/8 (37-630). Unless I want to pay obscene import prices my choices are limited. Is there anything to look for on a cheap, odd brand, tire that would provide clues about how long it will last? What do you look for when trying to assess how well a new tire rides? Like I said, to me a tire is a consumable. I'd rather have something usable that I bought cheap enough I can throw it out without an internal struggle when it gets worn or damaged, than running something I paid so much for I'm trying to squeeze every last K of service life out of it. What is the average life of a tire in my sort of riding? Additional info. On the bike;Badly weather checked, practically treadless, Bridgestone. If it fails catastrophically in local traffic I'll probably die. The choices (low to high);Leo Tires "Diablo", Philippine made, under $10 including new tube.Other tires in same price range from other nearby countries that have rubber plantations. Paying for a rim swap to let me use mid-price tires with known name brands. Paying astronomical single unit import fees to get those same brands in my current tire size. The budget doesn't allow a rim swap for at least a couple of weeks. So I'm mounting the Diablo before I leave the driveway again. There are no visually obvious defects or damage. Are there less obvious but still noticeable things I should look for? Small details that might keep this piece of crap from killing me if I catch them during a pre-ride inspection? <Q> There are many factors that go into determining the performance of a tyre. <S> The material and thread count (TPI) of the carcass, the rubber compound, thickness and tread pattern. <S> Tubed vs tubeless, and many different varieties of puncture protection layers. <S> Unfortunately as a consumer (especially with lesser known brands) its virtually impossible to be sure of the exactly how the tyre will perform without trying it. <S> This is why bike forums are always full to the brim of threads about x/y/z tyres. <S> The average life of a tyre varies significantly, based both on the tyre construction, the weight and riding style of the rider, and the terrain being ridden. <S> A light rider riding tyre 'X' on flat smooth roads may get 4500km out of a tyre, but give the same tyre to a heavy rider in hilly terrain and a coarse surface <S> and it may only last 1500km. <S> If you are looking at a tyre purely as a consumable item, and only care about how many km you can get out of them, then you probably want to look for tyres that are advertised as 'touring' tyres. <S> They typically have thicker rubber and a harder compound for durability, along with thick puncture protection layers which whilst designed to provide reliability in remote areas, also work superbly in urban environments <A> Quality of tires is mainly quality of rubber. <S> The rubber is responsible for the grip of the tire (braking and cornering) time to wear down rolling resistance <S> The second strongest indicator for quality is the carcass. <S> This determines things like puncture resistance behavior when cornering (you don't want to ride tires that "crawl away" in the corners) rolling resistance <S> All other features of bike tires (ignoring size, thickness is very important for application) are mainly cosmetic. <S> This includes the tread: You simply don't ride a bike at speeds that require tread to deal with water. <S> A fine tread may deliver better grip as it can lock into the stones within the road's surface, but a tread that looks like water-channeling does not give you significant gain in wet performance. <S> A good tire still works fine when it's a complete slick, a bad tire won't work with the "grippiest" tread. <S> TL;DR: <S> Quality of tires is largely invisible. <S> But you cannot judge a tires quality without taking the invisible stuff into account, which means you have to go by brands. <S> Sorry, I really hate having to say "look at the brand", but for bike tires, it's the only good quality indicator short of riding it. <A> Andy's answer is excellent. <S> In an attempt to add a little value... <S> It is difficult to know which tire will last longer when comparing between brands without experience. <S> However, within a brand you can get a pretty solid idea which tire will perform best based on the criteria you select by checking the company website. <S> Tire makers create products with specific characteristics and they rank their tires according to those characteristic. <S> For example (not a recommendation): <S> Continental <S> - Does not have categories like Schwalbe and Vredestein <S> but they do provide information that will tell you which tires fit performance categories. <S> As with anything, some companies provide clearer information than others. <S> If you are looking at two (or more) off brand tires you can get a rough "best guess" on durability by comparing the feel of the tire. <S> Max mileage will be found in tires with harder and thicker rubber which means they tend to be heavier. <S> It's all about trade-offs. <S> One of the trade-offs is cost. <S> It would take a lot of work to arrive at a miles per dollar statistic for enough tires to have a meaningful comparison. <S> For example, if I buy a tire for $20 that lasts 2000 miles and another tire for $40 that lasts 4000 miles (just making up numbers as an example) aren't I getting the same miles per dollar? <S> To really get picky you'd have to add in how much your time is worth to trade out tires. <A> Also worth noting, that some brands offer models of tyre that initially look the same. <S> Sometimes you will see a "bargain" online. <S> But manufacturers often ship lower qulaity OEM tyres (those that come with the bike) to those that are sold separatley. <S> It used to be the case that some Panaracer where made in Japan, but others came from China, with poorer quality rubber, threads per inch etc. <S> Other brands like Maxis might offer half a dozen variants of the same tyre, ranging from the cheapest rubber, to duo or triple compound versions, twin wall etc, which might cost twice the price. <A> Answering the follow-up <S> There are no visually obvious defects or damage. <S> Are there less obvious but still noticeable things I should look for? <S> Small details that might keep this piece of crap from killing me if I catch them during a pre-ride inspection? <S> I don’t think a sudden, catastrophic failure is likely. <S> I’d inflate them to the maximum pressure or slightly higher, then release air until you are at the desired pressure. <S> This is always a good idea to make sure the tire is properly seated and the tube isn’t pinched anywhere. <S> Make sure the tire isn’t bulging anywhere. <S> As long as the treads are intact even cracks or cuts in the rubber shouldn’t be an issue. <S> I think it’s a bad sign if a tire is really easy to install, since this could mean that it also comes off easily. <S> You can get an idea of the grip on various surfaces by braking with the rear wheel until it locks up. <S> I’ve had tires with terrible grip on wet surfaces, especially surface markings or manhole covers.
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You have to try a tire to gauge its quality. It might be possible to get better value from multiple less expensive tires than from one expensive one. Or check what other people say about the brand. Schwalbe = Rolling, Road Grip, Off-road grip, Protection, Durability Vredestein has: Rolling resistance, Comfort, Grip, Durability, Puncture Resistance
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New bike, tubeless tire will not inflate I got a new road bike with tubeless tires. I can't get the back tire to hold air. I got the front tire inflated but for some reason, as I am pumping the air all I hear is it coming out somewhere from the tire. I don't see a hole. It was shipped from another state and it came completely flat. <Q> There could be many causes for a flat tubeless tyre, especially on first installation. <S> Check <S> the tyre is actually tubeless compatible <S> Check <S> the tyre beads are seated the whole way round Check the nut on the valve is tightened (finger tight) With the wheel off the bike, shake the wheel and listen for sealant. <S> If any of these conditions are not met, rectify the problem before trying again. <S> To find the hole, get a helper to operate the pump for you, whilst you carefully inspect/listen to where the air is escaping. <S> Whilst still pumping (to generate some air pressure), rotate the wheel so the hole is at the bottom. <S> This will cause the sealant to pool in that area and plug the hole. <A> Tubeless tyres hold air only after being seated properly. <S> That means the bead is at the shoulder of the rim's flange. <S> Many tyres have to be inflated and under pressure to seal the bead. <S> One has to inflate them with more air per second going in through the valve then getting lost along the yet unseated bead. <S> For many MTB tyre-rim combinations a workshop compressor or tubeless charger (pump with air tank) is necessary. <S> Since you were able to seat the front tyre with your pump the following might be enough: Push each bead as far on the shoulder as possible. <S> Then pump very vigorously until you hear the beads pop into their place. <S> This can be very loud. <S> Also, a little sealant spread on the shoulders might help to increase the initial seal just enough. <A> Larger volume tubeless tyres need a good blast of air to get them seated, a track pump often won't get it done, especially if you've had a few tries and have got tired. <S> A compressor will do the trick but they're not always available, consider a tubeless inflator like an Airshot or the Bontrager FlashCharger. <S> When my tubeless tyres won't mount it can often be down to the tubeless rim tape. <S> Once it gets wrinkled or dirty with sealant the tyre can't slide up to the rim quick enough. <S> If this fails I generally replace the rim tape with new and it works first time.
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If they are all met, then you have a hole in the tyre - not at all unheard of in tubeless ready tyres which are designed for use with sealant. Try cleaning the rim tape and inner rim walls.
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Can this frame be used or is it done? I have a cheap mens Huffy mountain bike which I noticed has 2 holes in the frame. Would this be too unsafe to ride? <Q> It appears there is a crack connecting the two holes. <S> This would indicate there has been enough flex to cause the frame to crack. <A> I wouldn't chance it. <S> The entire frame appears to be extremely rusty. <A> The fork does not seem aligned with the headtube. <S> So, yes, the bike is unsafe to ride. <S> and there on the frame. <S> And they are in dangerous positions. <S> Finally: think about yourself sprinting through an intersection (possibly green-turning-yellow traffic light), the frame cracks and your bike comes to a sudden stop (frame hitting rear wheel, rear wheel locking). <S> It is not dangerous, as long as a truck is not coasting for the red-turning-green traffic light in the other direction ...
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If it were mine I wouldn't ride. If by chance the fork is straight, the two holes you see there are just a sign of what can happen to the other spots rusting here
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Commuter bike for better performance: less weight, or internal gear-hub? Background I commute daily to work, the ride is about 10 km each way, across the city. The path is mostly streets with intersections, and a few long cycling lanes. Some hills here and there: Strava cycling app says 'Elevation Gain' is 80m. I'm currently riding a Trek Valencia hybrid bike (2011), it's getting a bit old, and I'd like to replace it. I'm looking for the same kind of acceleration / responsiveness / sporty ride, but possibly getting me to make less effort to get the same performance (or get earlier at work). Options I want hydraulic disk brakes, good quality gear set, and rather an aluminum frame. I checked what local bike shops recommend, and I'm now hesitating between two options. Unfortunately, trying the bikes is not an option, as no shop has them in stock. Stevens Strada 900 (2019) product page It has quality components and is lightweight. I'll need to add mudguards and a rear carrier though, so it will be a bit heavier than the announced 9.4 kg. Gears: 2 x 11 Shimano Ultegra R8000 Cube Editor black'n'purple (2019) product page This one looks interesting to me because of the belt drive. This would make the rides smoother, and avoid loss of efficiency in the long run. Gears: Alfine 11 gear hub Questions I read posts with figures about the gear ranges of both systems, but I'm having trouble getting a clear picture. Some articles: stackExchange post , internal gear rations measurement , this post and that one . How likely am I to get in situations where the speeds of the Alfine 11 gear hub don't switch correctly anymore? Are the 2 kg less from the Stevens likely to make a noticeable difference in terms of energy efficiency? Will any of the bikes above provide a range of speeds comparable with what I currently have (mid-end 3 x 8 derailleur)? I had the opportunity to try a bike equipped with a Shimano Nexus 8 gear hub, and there were definitely not enough 'high' speeds. This would prevent me from riding fast enough on flat lanes, or downhill. Or to summarize, perhaps: more lightweight bike with derailleur or Alfine 11 gear hub, which would you recommend for my use case? Any input and tips appreciated. Thanks, P.S.I also read the answers to How to improve my performance on a commute? and will probably follow some of the recommendations in there, like getting clipless pedals. <Q> I use 2 bikes, with a train ride in between. <S> The bike I use at my work town rarely gets maintained. <S> I take it home 2 times each year. <S> The only things I do regularly is pump the tires and lubricate the chain. <S> Even then it keep riding as good as new. <S> The derailer bike I had here before that needed a lot more care. <S> The things I learned over the past years: <S> The simpler the better. <S> If the terrain is flat enough to get by with a bike without gears, do so. <S> 80 <S> m elevation is on the edge, and depends on your physical condition. <S> If you feel the upper gear on a Nexus 8 is not large enough, you're riding quite fast (35Km/h+) already. <S> I ride a bike with an Alfine 11, and have no problem doing 35 in 8th gear. <S> Another thing is adjusting your style to spin faster (85+RPM), which generally is also better on the knees. <S> No front shock absorber. <S> The good ones are too expensive, and the other ones too heavy and crap No V-brakes or cantilever brakes. <S> At least hydraulic rim (Magura) or disc brakes Mudguard! <S> A rack to hang bags <S> (I am very happy with bags like this ). <S> No backpacks for me. <S> A IGH is a lot more carefree then a derailer. <S> being able to shift at red lights is very handy <S> The lights have to be driven by a dynamo and fixed to the bike (battery lights get empty or forgotten at the worst possible time) <S> No NuVinci. <S> It is heavy, and you can't shift when stationary <S> So I would not use either of the bikes you suggested, but something like this or this <S> I don't have an opinion on chain vs belt. <S> My girlfriend has a bike with a belt, and that tends to stay cleaner then the chain on my bike, but I don't know whether it is worth the extra expense. <A> I have only three things to add: I would definitely get a bike with hub dynamo and fixed light. <S> Even if you ride during daytime, having the lights on gives you added visibility in traffic and the price you pay in weight and added resistance is negligable. <S> If your hills are not as steep to need all the lower gearing of the Alfine, you could make it faster by simply exchanging the chainring for a larger one. <S> Don't buy the bike without a test ride. <S> I disagree that you should use a cheap bike for commuting if you can afford a better one, as long as you have a safe place to put it at work. <S> Simply because those 100 km/week will probably be a major (if not the biggest) part of your overall cycling, and why use bad equipment if you don't have to? <S> Compared to using a car, even a mid-upper range bike is still very cost-efficient. <A> An extra two kilograms on your bike would weigh against your total mass (you plus the bicycle plus your backpack plus your water bottle plus your helmet and sunglasses and ...). <S> When rolling slowly (and not accelerating) or climbing hard, there's little difference between my fat bike and my road bike with 25mm tires, with the difference in mass being 105 to 110 kg (rider, water, backpack, bicycle, helmet, ...). <S> (when accelerating, the 26x4.0 wheels on the fat bike gives it a majestic and ponderous feel - fortunately, braking performance with hydraulic discs is superb). <S> As for the efficiency losses... current top of the line chain and gears are 97+% or so percent efficient (based on numbers thrown by the GCN for CeramicSpeed bearings and that new gearshaft transmission for bicycles), so any improvement on that is worth only for races (you might choose the "no maintenance" mode of belt drive and internal gear hub, but any efficiency deficiency can be ignored). <A> I have an Alfine 8 with the Gates belt as pictured on that Cube. <S> I use it for commuting, and carry about 5kg of stuff in my rear panier, bringing the total weight up around 15kg. <S> Add on top of that the Gates belt, and you're avoiding most of the issues that come along with a chain. <S> I don't know the quality of that specific brand of bike, but the components are top notch. <S> The internal gear hubs do sometimes take a bit to switch, just like an automatic transmission in a car. <S> If you keep your foot on the gas pedal, you're less likely to have it gear up; similar to this, the bike hub will typically avoid switching while there's active force being applied through the system. <S> Stop pedalling for a split second while you switch gears and you shouldn't have any issues. <S> In my experience, the gear ratio between an internal hub will out pace a typical derailleur commuting bike. <S> Typical cruising speed is 20km/h. <S> My Alfine 8 tops out at around 35km/h, where the pedals just don't do anything in top gear after that. <S> The 11 might have a bit of a higher top speed, but commuting tends to be a lot of stop signs and red lights that you will stop at.
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When you use your bike every day, reliability is as important as weight. With the Alfine 11, you may find that you skip pretty quickly past the first couple gears, but they'll help your acceleration and reduce the amount of torsion you place on your crank. You likely won't be able to compete with a road bike. I haven't ridden on a derailleur bike in almost two decades because the internal hub is so much more reliable in the weather.
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Am I over weight for this bike I bought My weight is 240 pounds (109 kilograms). I bought a miele velo gr1 they said it will hold my weight but wheels only have 32 spokes. Are they right? <Q> The bike should be fine for your weight, assuming you use the bike for its intended purpose. <S> Which would be on-road riding, not off-road riding or other high impact activities. <S> For your information, 32 spokes is not that little, wheels with less spokes are also often rated for up to 109KG. <A> After searching the Miele site for a rider weight rating and finding no rider weight limit specification I turned to Trek for a roughly equivalent bike thinking that a similar bike would have a similar rider weight limit. <S> (per pateksan's suggestion) <S> Trek rates their bike at: <S> Weight limit <S> This bike has a maximum total weight limit (combined weight of bicycle, rider, and cargo) of 300 pounds (136 kg). <S> I've ridden a bike with three full grown men on it - point A to B on a smooth surface - with no problems. <S> You will be fine. <A> Apparently this is a Tour de France bicycle, so the rider would probably weigh less than 70 kg (or some 150 pounds). <S> However, it has 16 or 18 spokes on the front <S> (I think).So, a well made wheel should be strong enough for its intended use. <S> However, check the warranty terms related to wheels "out of true" or broken spokes - and considering you are at the top weight range, use the maximum recommended pressure in tires and check often.
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Even Trek's least expensive hybrid bike, the FX 1, is rated at 300 pounds. The Trek Verve 2 disk bike is in the same price range with an aluminum frame and 32 spoke alloy wheels.
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The palms of my hands really hurt I understand that the pressure on my hands causes it.I also understand how the nerves run through my hand. What I don't understand is how to implement the advise of, "Take the weight off your hands" A fellow told me, "Put 90% of your weight on the pedals, 10% on the seat, and barely touch the bars with your hands." I dunno how to do this! With the seat up in order to get a full pedal, the angle of your body is going to naturally push down on your hands. The only way I know to "put weight in the pedals" is to stand up. Short of getting a raised handle bar or lowering my seat, how do you get the weight off your hands? Is there some kind of posture magic I can't figure out? <Q> You are correct that a leant-forward riding position will naturally tend to make a rider support some of their weight with their arms and hands. <S> The more rotated forward the rider is, the more weigh the arms tend to have to support - which is one reason <S> tri-bars have forearm rests. <S> Good core strength is what allows a rider to take weight off the arms. <S> Strong lower back and abdominal muscles support the torso, taking weight off of the arms. <S> You can try doing some core strength building exercises (which will likely make you a stronger rider and help prevent injury as well). <S> You should look at your fit on the bike, you may in fact have the bars too far forward and down. <S> Raising and pulling them back may help while you build core strength. <A> You use your glutes (and maybe a bit of your erector muscles) to hold your torso up. <S> If you're significantly forward, like an aero posture, then your hamstrings will probably be engaged too. <S> The more pressure you keep on the pedals the easier <S> it is. <S> Lean forward 45 degrees from your hips. <S> You'll get tired eventually, but you can probably hold that for at least a few minutes. <S> If necessary you can do exercises to strengthen your glutes. <S> One of the show-off things I used to do is run at a hill, then charge up it with my hands clasped behind me. <S> It looks impressive, but it's actually easier to ride (bent over) without your hands on the bars if you're working harder, and especially if you're going uphill. :) <A> Fairly hard to answer and probably requires a play with bike fit - a visit to a bike fitter could be worth considering. <S> Geometry and size - some bikes are more likely to force you into a position that loads the arms than others. <S> You can look to address this though adjustments such as bar height, seat position, stem length. <S> Note the current MTB trend of super wide bars effectively lengthens the cockpit. <S> Narrow bars might help - you can trial this by moving the grips (if the style allows it) and controls inboard before cutting bars down. <S> Riding style <S> - When you ride are your shoulders and arms relaxed and guiding the bike, or tense and controlling it. <S> Is your position correct (attack position, bent arms, torso level), allowing the bike to freely move around under you, or is it upright and tense, forcing you to move with the bike. <S> Fitness - whats you upper body stamina like? <S> Hows you core strength? <S> If you riding style is perfect, you can do a lot of riding without relying on brute strength, but few riders (I do not include myself in that group) have perfect style and a bit of fitness helps a lot. <S> One thing that will sap arm strength is gripping the bars - either holding on tight or brakes - poor brakes and over use of brakes. <S> Braking should be gentle and controlled (Ideally with one finger), not jabbing them on with the whole hand. <S> If you holding too tight, it saps energy and you loose feel for the bike on the trail. <S> Think of it as a soft touch in partnership with the bike rather than a firm hand fighting and controlling the bike. <A> Something that isn't mentioned in the other answers is the attitude of your saddle. <S> If it's tipped forwards (front lower than back), that will tend to shift weight onto your arms. <S> You might want it at a slight angle for, ahem, comfort down there, but it should probably be within a few degrees of level. <A> If you have the correct sized bike, correctly set up, with a pair of decent gloves, you'll need some saddle time so your body becomes accustom to riding. <S> However; if you really want to ease the pressure on your hands you will need to start engaging your core, you need to work on your abs/glutes and supporting muscles. <S> While riding on a flat, even, quite road, make sure you're in the correct riding position and put your hands behind your back keeping your body where it is. <S> See how long you can hold this for. <S> If you want to take this exercise to the extreme, use a stationary indoor exercise bike (spinning bike). <S> Make sure you've got enough resistance to support your weight(need to look after the knees), stand straight up on the bike as if you're on a tough climb and slowly remove your hands from the bars, your abs should be supporting your upper body, you should maintain a proper pedal stroke. <S> This exercise, if done correctly, will do two things; point out flaws in your pedal strokes and will force you to use your abs. <S> If you have an 8/10 resistance and can transfer from a seated position to a standing position with no hands, no wobbles and no messed up pedal strokes you'll notice how much better your hands and shoulder/neck feels after long rides. <A> Go down to your local friendly bike shop and make sure that the bike is fitted correctly to you. <S> There are so many variables at work here that it is difficult to pinpoint any one cause. <S> The best place to start is at the beginning. <S> After you have made sure that the bike correctly fitted to you, than you can work on a solution (if your palms still hurt). <S> There are also many articles on how to fit a bike, if a bike shop is not readily available, perhaps they can help.
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Either way the hands need to be relaxed on the bars, holding on enough to guide the bike and keep the rider connected (both physically and mentally) to the bike. Swept bars can also help reduce the effective cockpit length. Stand with your feet planted.
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Converting 3x7 to a 1x7. Is it possible with only existing parts? I own a 2000 model Specialized Ground Control full suspension. The front derailleur is rusty and temperamental so my solution is to remove it as well as 2 chain rings (they are removable on mine) and convert to a 1x7. This bike is not worth high spendings on upgrades so would this work if I just bought a 1x drivetrain specific chain ring and kept everything else stock? Better yet would it even work on the current middle size chain ring with maybe a chain guide attached to keep it held on? If spacers are required that's all good. I am only a novice MTB rider and the bike will predominantly be used for downhill and small jumps, no hectic double blacks or anything. I am aware that 1x7 isn't very versatile but it will be plenty for me to have fun. <Q> You have a zero cost solution, which is to keep the front derailleur but remove the cable (and shifter if you like). <S> Then use the FD limit screws to fix it in the right position to act as a chain guide. <S> You don't need a 1x chainring, in fact using one with a 7 speed chain is probably less than ideal, so you're actually better off sticking with an existing chainring. <A> If the chainrings are in good order, I would recommend servicing the front derailleur and continue to run it as 3x. <S> The reason is that front dérailleurs rust quickly but are often chrome plated and it’s actually easy to remove the rust. <S> If the derailleur is temperamental it is typically solved by replacing the shifter inner cable ($1 on eBay) and readjusting the limit screws. <S> Yes it will take up some of your time, but it would cost close to nothing and you will probably appreciate the wider gearing on some occasions. <S> Also, as noted by others, you’ll still need the front derailleur as a chain guide so you would still see the rusty thing if you would run 1x. <A> Yes, it's doable. <S> You'll have terrible gear ratio range <S> but you realize this and don't mind. <S> Either find a narrow-wide chainring that fits the crank, or leave the middle ring in place. <S> You may need shorter chainring bolts as the existing ones have to be long enough to go through the middle and large rings. <S> You can remove the shifter but leave the front derailleur in place to act as a chain guide, if you can wind out the lower limit enough or otherwise fix it over the middle ring. <A> I've done this, converting a bike from 2x11 to 1x11. <S> I removed the big ring, front derailleur, and the shift cable. <S> I did need parts, but only shorter chainring bolts. <S> If you don't want to do that, you could leave the big ring in place, or rig some kind of shim or spacer. <S> I did run into one problem, which was that the chain dropped off the chainring several times an hour. <S> There are many gadgets on the market which try to prevent dropped chains. <S> I ended up getting one of them (a chain guide), and I'm quite happy with the bike. <S> But if you want a minimum-cost solution, Chris H's suggestion -- to use the front derailleur as a guide and adjust the limit screws to position it -- sounds good to me. <A> I run a small bicycle hobby shop. <S> I have been doing 21 to 7, and 24 to 8 conversions for as long as I can remember. <S> The conversion can even be done with a riveted crankset that has no bolts in it. <S> I carefully drill out the rivets or spot weld that hold the 3 chainrings together, throw away the big and small ring, and keep the middle ring. <S> Typically in these one piece setups the crank arm is fastened to the middle in 9 out of 10 cases. <S> Then remove the front derailleur, shifter and cable. <S> I remove between 4 to 8 links from the chain. <S> I have never had any one complain about their chains jumping off the front sprocket. <S> Sometimes I will change the bottom bracket to improve chainline. <S> This conversion has been fool proof for me and my customers.
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You may not be able to get rid of the big chainring, or you may need to get shorter chainring bolts if you do, depending on how the big and middle rings are mounted.
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Why doesn't my new SRAM XG-1295 cassette bolt turn freely? I am trying to install a brand new SRAM XG-1295 cassette. I watched many videos and it seems very straight forward. Place the cassette on the freehub, match the splines in back, tighten with a cassette tool. But for some reason, the bolt(?) on the cassette does not turn. This has nothing to do with the freehub. I'm holding the cassette in my hand, trying to turn the bolt but it does not turn. Any help would be appreciated :) -MIke <Q> It sounds like you solved the problem, so I'm going to hijack this thread slightly to provide some general info. <S> The cassette you have uses the SRAM "XD" technology, which is unusual in using a "lock tube" instead of a traditional lock ring. <S> The lock tube is integrated into the cassette and enables the cassette to have the otherwise too small 10-tooth cog. <S> The tube is the part marked in the OP's photo. <S> Although the OP's problem is with the movement of the locktube within the cassette, there have been a number of complaints in the past few years about the locktube seizing against the freehub, since there is a significant surface area of contact between them. <S> Very often the result is that both the cassette and freehub body must be replaced. <S> Search "SRAM XD cassette seizing up" for stories. <S> The take-home message is that you should liberally apply grease or anti-seize to the freehub body whenever installing this type of cassette! <A> I'll add an update for those who come looking for help with this... <S> AS I DID! <S> I called SRAM tech support, and they said the tube not spinning in a new XG1195 (X01 10-42 11 speed <S> ) cassette is normal. <S> The tech told me thread it on with the proper ParkTool FR-5.2GT tool (which I have) and take your wrench to it. <S> When it bottoms out, use your inch pound torque wrench and tighten to 40NM. <S> I asked about peoples comments in forums saying people break the tabs with that tightening spec, and he said if your tools are good and your torque wrench is remotely accurate, in no way should that be a concern! <A> I had the exact issue - a new SRAM XG-1295 cassette whose lock tube would not turn. <S> Since it was new I didn't want to apply too much force and strip the splines or break something. <S> After reading this and a few other discussions it became clear that the lock tube was probably stuck. <S> I put a bit of chain lube between the smallest cog and the large shiny clip that holds the cogs to the lock tube. <S> After giving it a couple of minutes to penetrate I tried to get the lock tube to move <S> and it freed up with much less force, but not too easily. <S> It was too tight to hand-turn which made me a little nervous threading it onto the rotor with a big wrench. <S> All is well though, it went on just fine without cross-threading - time to ride! <A> So the problem was that the locking nut mechanism was stuck. <S> This is a $495 cassette <S> so obviously I didn't want to force the thing for nothing. <S> I put the tool in a vide and wrapped a chain whip around the cassette and forced it. <S> It made a little snap sounds and now it moves. <S> Though not very freely. <S> Usually you can hand tighten to start off, I'll have to use a tool the whole way. <S> Thanks to those who commented and tried to help :)
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Compounding the problem is the fact that the splines on the lock tube have a very low profile, so when excessive torque is applied to try to turn a seized lock tube, the splines shear off. The tech told me if the tube spun freely by hand on a new cassette that would likely be a problem.
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Old time bike. Can I put a rear derailleur? Hi guys,I am looking to build up an old timer bike and I have found this frame. Can I put a rear derailleur in that socket? <Q> Yes, that is a standard derailleur hanger. <S> Before attaching a derailleur, make sure that the hanger is aligned straight. <S> There are tools to do this, but you can usually tell by eye if it's out of alignment. <S> On a steel frame like that one, you can typically bend the hanger back into alignment with no problems. <S> Also check that the threads are not stripped. <S> If you're not familiar with a helicoil, search "rear derailleur hanger helicoil" for examples. <S> They will usually come with instructions for installation. <S> With regard to the dropouts, horizontal dropouts were standard on bicycles for many decades, whether they were single-speed or multi-geared. <S> Look at pretty much any picture of a bike from before the late 80's. <S> The only difference from a vertical dropout frame is that you have to pay a bit more attention to aligning the wheel properly in the frame when you put it on. <S> Check that the wheel is properly positioned with respect to the brake pads and that the rim is equidistant from the chainstays. <S> From your picture, though, it appears that the dropouts on this frame have stops in them, so that you can simply pull the wheel back against the stops. <S> If they are set up correctly, the wheel should be aligned properly when seated against them. <A> Shouldn't be a problem as the frame/bike originally came with a rear derailleur. <S> Since the frame is steel, you can spread the rear dropouts to accommodate just about any width rear hub out there. <S> There are many articles on the web on how to do this. <S> You should be fine with any narrow six, seven and eight speed group of components as they are all pretty much the same width. <S> If you run an older five speed chain, then the freewheel and cluster must match as those chains are a little wider, the same for a ten plus speed as they are narrower. <S> I have run nine speed derailleurs with eight speed clusters and nine speed chainrings with eight speed derailleurs with good results without having to shim the jockey wheels or the chainrings. <S> I have a bunch of steel bikes dating back to the late sixties and yours is definitely worth saving. <A> Thank you guys for your info and everything. <S> The first bike was a little bit strange with the brakes, rear dropouts and all this stuff <S> so I found another one. <S> Road bike, 57cm, 2×6 speed. <S> I'll start by putting a flat bar, flat bar brake levers and that's it. <S> Later I'll try to put a 9 or 10 cassette.
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Just make sure that the chain, derailleur and freewheel/freehub match in respect to speeds! If the threads are damaged, you may be able to use a thread tap to clean them up, or in the worst case, insert a helicoil.
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Removing powder paint from threads Bought a aluminum frame with rear suspension, got it sanded and powder paint. While they matched the color perfectly, it's smooth and evenly distributed BUT UNFORTUNATELY totally forgot to cover any threads. Managed to remove the paint from bottom bracket threads, seat post tube and frame head tube with a copper brush, sandpaper and gently using an awl. Problem is the #5, #6 threads for equipment and derailleur which is a part of a frame. Could use a tap on #5 and #6, but the threads aren't damaged so there's no need as they are undamaged. Any way to remove the paint chemically? Tried a hydrocarbon solvent that I left for 4 hours without slightest effect. <Q> Derailleur mounting bolts are an unusual size, but assuming you've got a removable hanger that should be held on by a normal metric screw (M6). <S> Metric M5 screws are common for bottle cages, mudguards etc. <S> Normally you'd put a few drops of oil on the tap for actually cutting a thread. <S> When cleaning a thread, grease can be better as you'll pick up more of the muck with it (and leave the threads nicely greased). <S> If you've got a full set of taps, a second cut tap or even plug tap is enough for cleaning threads, and easier to start without cross-threading than a taper tap. <A> A die (of tap & die ) is exactly what you need to use. <S> It will clean the powder off the threads in a single pass. <S> When you use the die, remember they are directional and you want the bottom of the die facing away from the wheel. <A> I got my frame powder coated and asked what to use to degrease it <S> should I want to paint some pin striping or place some decals. <S> So perhaps try acetone <S> (the same the ladies use to remove their nail paint, only they use the small bottles and men use the litre bottles) to soften the coating where it needs to be stripped? <S> Be careful not to run it on the surfaces that must stay intact.
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Taps are useful for cleaning threads, and much better than forcing a screw down the hole (though that can sometime be enough). They told me not to use acetone because acetone will make the powder-coat dull and will soften it.
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Do I need a shock-proof watch for cycling? I've just started cycling longer distances as a hobby (I cycle for my commute daily). My watch isn't waterproof at all so I don't take it with me but on my last ride I found myself getting annoyed at regularly having to rummage in my bag for my phone to check what time it was. I don't want a fancy GPS or sports watch that measures anything except time. Obviously it would need to be waterproof enough for heavy rain (100m+? 30m?). Would a simple digital (no moving parts to dislodge on a rough road) waterproof watch do the job or does it need to be shock proof (ie. G-Shock or similar) as well? <Q> There are no special requirements for a watch for cycling. <S> Rain or road buzz might damage rather sensitive watches. <S> Fixing a defect, loading the bike, or a crash also gives opportunities to damage a watch. <S> Common sense will suffice to know when to take your horological masterpiece or leave it at home. <S> In other words, there's a difference between riding to an opera and doing sports. <S> Most mechanical watches, for example a Seiko or something with an ETA movement, shouldn't be troubled by road buzz or the occasional cobble stretch. <S> Please check reasonable voices in a watch forum. <S> Much sports riding is on a different level of impact, vibration, and risk of damage. <S> In other words, mechanical watches are perhaps not the best choice for downhill MTB. <S> A decent quartz watch or a G-Shock (analogue or digital doesn't matter) are preferable. <S> Still, a dollar store digital will perform as well as the G. <A> Why not go for a cheap and simple bicycle speedometer? <S> Apart from the time it can also show you speed and distance which is always nice to know. <S> As gschenk said, there are no special requirements for a watch while bicycling, but I do think that it can get uncomfortable. <A> I've got a digital G-shock that's lasted >12 years cycling, kayaking, etc. <S> It's massive overkill, and rather massive which is occasionally uncomfortable (some combinations of winter gear and hand positions). <S> A rather slim water resistant digital Casio with a backlight would be plenty (<£/$/€20). <S> They're pretty tough, surviving most things except impacts dircetly on the face. <S> I suggest digital after killing a G-shock by dropping it from head height onto tiles and breaking off the second hand; analog watches have extra failure modes. <A> Durability is only an advantage if you don't overpay for it. <S> Identify the situations that will happen regularly: rain, having to carry your bike, etc. <S> Then find out how much a watch which is able to withstand these situations cost. <S> Such a watch will last several years on average, before a rare accident (hard crash, falling into water, etc.) will kill it. <S> Now check out the price of that fancy shock-proof watch you wanted to buy. <S> Do you think it will last twice as long? <S> In that case, only buy it if it costs at most twice as much. <S> I know this sounds very approximate, but <S> with many fancy sport watches you'll find out that it will take more than a lifetime to justify the price. <A> In my opionion, if there is only need to know hour/speed/distance - basic information , then there is no need of expensive watch, just buy normal bicycle counter which usually are waterproof enough for heavy rain. <S> If you want to check your current pulse then there will be need for watch with chest band there are cheap and simple watches which check your pulse only. <S> But this sollution won't give you information about speed/distance/GPS <S> If you want to have <S> all data - GPS/time/speed/hour/distance/pulse(wrist) etc... <S> Watch will be more expensive - on my own <S> I use Garmin Forerunner 35 which isn't expensive. <S> Have a great day :) <A> Any watch with moving parts will suffer more than a digital watch. <S> Many will site the toughness of diving watches but those watches are tough in a very specific environment i.e. in the ocean. <S> On a bike or many other sports, you want to be able to see the time or other information quickly, really quickly, if you are travelling at speed. <S> A digital watch has a big digits to read, watches with hands don't. <S> Plus many watches with hands if they have extra features are accessed through the crown. <S> A digital watch you just hit one button to get the function you want. <S> Another advantage of a digital g-shock is you can set it to auto illuminate. <S> Get a g-shock they range from cheap to bling. <S> I particulary like the solar versions. <S> In my experience people buy a fancy watch tiso t-touch, garmin, suunto, but when they get smashed, break you see old hands in outdoor profession revert to a solid affordable digital watch G-shock dw5600 or similar. <S> Look at what the professions use, outdoor instructors, military, police, basic digital. <S> My previous g-shock solar lasted 20years, still works <S> , I gave it to my dad, then bought another G-shock. <S> A watch which you never have to consider, used it climbing, downhill biking, kayaking, roofing, demolition, building work, just does not care. <S> Yet friends around me, "oh i just need to take my expensive watch off" before doing <S> x, y or z.
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A cheap watch from the supermarkt will do as well as a decent quality watch or a sports watch (besides sport-specific functions).
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How do I know what gear combinations should work without chain rasp on front derailleur? I tried adjusting the front derailleur on a 3x10 trekking bike. After fiddling around a long time, I concluded that is probably not possible to make all cogs work with all chainrings. How do I know what gear combination should work? Should you for example be able to use the fifth gear with all three chain rings without chain rasp? Should you also be able to switch between all chainrings in the fifth gear? Currently, the three largest cogs are only working with the smallest chainring. If I adjust the front derailleur to allow shifting on the second chainring, I lose the ability to downshift from the third to the second chainring in higher gears (the chain rattles but does not come down). I also experienced something similar when I crosschain on a 3x8 city bike. I have never had any issues with a 3x7. <Q> There are two approaches here: <S> The standard rule is to avoid cross-chaining. <S> It means that you don't use large with large and small with small. <S> The large sprocket at the rear should not be used with the large ring at the front. <S> In the same manner you should not use the smallest rear sprocket when your chain is on the smallest front ring. <S> In both cases the chain runs quite diagonally or sideways when you look from above. <S> It puts a lot of strain on the drive components and the chain is most likely to rub against the front derailleur plates. <S> With a triple the use of the middle ring is less critical. <S> It may work with any rear sprocket. <S> The previous being quite old school, newer derailleurs and narrow chains are less affected by cross-chaining, if you leave out the higher wear of the drive train. <S> Especially modern indexed front derailleurs don't have just three positions but two for each chainring or even three for the middle one. <S> You can notice these if you carefully actuate the shifting. <S> You will notice that when the derailleur is as far right as possible, a slight touch of the lever will have the FD move inboard ever so slightly without throwing the chain off. <S> This position is meant to be used with the larger rear sprockets. <S> It will only work with carefully adjusted indexing of the derailleur which may be fiddly. <S> Some makes, like SRAM have FDs with a special geometry of the plates that doesn't require trimming where electronic shifters trim the position of the FD according to the position of the rear derailleur <S> Note <S> : in the days of non-indexed shifting and down-tube levers it was customary to the adjust the position of the left lever slightly when the 'ear-meter' registered noise from the chainrings. <A> You should normally be able to access all gears at the back, whichever gear you have selected on the front derailleur. <S> Then it comes down to how many gear combinations you can achieve noise free. <S> Shimano have a bunch of tech docs for setting up derailleurs, a general one is here: https://si.shimano.com/pdfs/dm/DM-FD0003-06-ENG.pdf <S> and it has a good run through of front triple adjustment. <S> You could follow this through and see if you manage any improvement. <S> See the note on page 4, they expect some rub when cross chained whichever ring you’re on and suggest you deal with it by changing the gear <S> so you straighten the chain out. <S> Learning from them expands what you think is possible. <S> Personally, I expect (with a triple) to access all gears without chain rub when using the middle ring, and to have a little chain rub when fully cross-chained from the small and big rings. <S> I.e. in small-small or big-big only. <S> As you’ll avoid cross-chaining the extremes, this would be adequate for majority of riders. <A> I have found that in some instances you can make adjustments that allow either the use of most of the smaller cogs or most of the larger cogs but not both. <S> I have seen cases where you can reduce the chainrub on the derailleur but at the expense of only being able to drop to the smallest crank ring if the chain is on the 4 largest rear cogs. <S> You need to decide which setup is appropriate for your riding style. <A> The chain is most likely to rub the front derailleur cage when: It's at either its most inboard or outboard positions <S> , i.e. lowest and highest gear ratios: small chainring/largest sprocket or large chainring/smallest sprocket. <S> The chain will rub if the derailleur limit settings are too tight. <S> When the angle between the chain and the cage is greatest, i.e. during extreme cross chaining: large chainring/largest sprocket or small chainring/smallest sprocket. <S> With the chain running across the derailleur there's less clearance on either side. <S> You really should be able to set up a modern 3x10 drivetrain to shift properly without rub in the lowest and highest gear ratios. <S> Rub when cross-chaining is less of a concern as you should be avoiding that anyway. <S> One thing to look at if you are having difficulty is the derailleur cage angle. <S> If the cage is yawed in out out a little too much that may be the cause of you rub problems.
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Better mechanics can set up many derailleurs without chain rub in any gear combination. But still, depending on the position of the chain, rubbing against either FD-plates is possible, so you should avoid the use of the two extreme sprockets. While it is not unusual to get some chain rub on setups using 8 or more speeds as @Carel has stated, in general cross-chaining should be avoided for the reasons stated. Then again, there are so many variables, in the components, speeds, bike geometry, tyre widths etc, that knowing what is the best you can get from a set up depends on your preferences, your skills, and the bike itself.
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Rear derailleur got caught in the spokes, what could be a root cause I have several problems on this bike. Here are the elements that have failed and other pieces of information: the chain has derailed past the largest sprocket the rear derailleur has rotated 180 degrees, and is caught in a spoke (between the frame of the derailleur and one of its sprockets) half of the derailleur is now bent 45 degrees from its frame (derailleur on picture 2 should be U-shaped, not V-shaped) sprockets showed some signs of wear, but not to the point where it causes the chain to skip when load is applied the threaded hole to which the rear derailleur is screwed shows some sign of wear ( this is a modular part which is itself screwed to the frame) rear axle is broken in half right in the middle. I don't have the tools right now to open it, I believe this requires a punch and a hammer to remove the cog set.. Right now I have already lost some bearing balls after I moved the axle from the dropouts. Now I'm wondering if there is a single failure that could explain what happened. Thanks to the answers, I inspected the derailleur closely and found this: There is a missing chip exactly where the L screw is supposed to hit the frame. Apart from that and the fact that it's bent beyond repair (IMO) the derailleur is actually brand new.. Here is a picture of the broken axle I knew something were really wrong when bearing balls started falling on the ground... <Q> If the low limiter screw on the rear derailleur was very badly adjusted, it would be possible to move the derailleur far too far past the end of the cassette by shifting into the lowest gear (i.e. shifting onto the largest cog on the cassette). <S> There's a lot of information on setting derailleur limiter screws on the internet - here's a fairly good example <A> (in addition to Diado's answer) I would suspect a bent derailleur hanger. <S> Usually the derailleur cage should be perpendicular to the wheel's axis. <S> When the derailleur hanger is bent (it's said that happens when the bike falls over or when squeezing it into parking positions) <S> it will often be bent towards the wheel. <S> I've seen bikes where this goes so far that the cage touches the spokes on the smallest gear, even when the limiter screws and cable tension are adjusted correctly (i.e. the small wheel in the derailleur is spot on at the largest cog, and screwing in the limiter would prevent reaching the smallest gear). <S> One of these bikes experienced the same damage as yours when shifting into the smallest gear at high speed. <S> Never happened at slow hill climbing, we suspect vibrations at higher speed pushed the derailleur just that little bit further in to get caught in the spokes. <A> As for repairs... <S> Axle - you're up for a new axle. <S> Check the condition of the cone nut and their bearing surfaces <S> - they may be okay but any dents or pits and they're better-off being replaced. <S> - they are much more expensive to replace so minor damage to bearing surface you may choose to accept. <S> Bearings - Do just replace all the bearings in the wheel too - even if you saved them all they will be worn. <S> Ball bearings are cheap. <S> Derailleur - needs more inspection <S> but I'd replace it. <S> The bent bits may be straightened, but the missing limit stop for the large cog is going to be fiddly. <S> You could braze or solder something in to act as a stop, but any repair could fail repeating this whole problem - not recommended. <S> Transmission - I suspect the chain and cassette will be okay, but do clean and inspect them for damage. <S> Spokes - again inspect. <S> Its possible for the Drive Side spokes to get munched at the bend where they enter the hub, leading to premature spoke failure. <S> Decide if damage is minor scratches or significant gouges, and replace the worst spokes first. <S> Daniel rightly points out that a spoke protector disk can be installed between the cassette and the wheel, which will save your spokes if the chain jumps over the top in the future. <S> They're cheap and a good idea for this kind of bike. <S> Frame - your derailleur hanger looks bent in the photos, but hard to know. <S> Its a replaceable part so consider just buying a new one. <S> They're not cheap, but they are much cheaper than a replacement frame. <S> You can do this yourself with time and effort, and its quite rewarding to fix it yourself. <S> Or you could involve the borrower to help, depending on the social situation. <S> Once the repairs are done, you will need to fine-tune the rear gears and limit screws to ensure they're in the right place to stop this happening in the future.
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This would move the chain off the top of the biggest cog and could force the derailleur into the spokes which, in turn, would bend it. Wheel - Inspect the wheel's cups too I'd remove the cassette and any plastic protector, clean down and look closely at the elbows.
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9/16 pedals wont go in crank - they're too big What about if you have two gears on the crank. I used a 5/8 open wrench to take out my original pedals on my Schwinn Sierra and the new 9/16 pedals won't go in - they're too big. What size would it need? I'd like to use an adapter. <Q> First verify that you are in fact trying to screw the left pedal into the left crank arm and the right pedal into the right crank arm. <S> The pedals are sometimes marked with a R and L on the end of the threaded section. <S> The left side is the side your left hand is on while riding. <S> There are 2 common size pedal threads. <S> Many children's bikes, some lower cost department store bikes and some folding bikes use 1/2" thread on the pedal . <S> Most others use a 9/16" thread on the pedal. <S> My guess is <S> you bought 9/16" pedals and they are too large to screw in to your crank arms. <S> While they make adapters to use 1/2" pedals in 9/16" holes there is not one for the reverse. <S> As an alternative you can ask your local bike shop to determine if the crank arm has enough material to modify it to the 9/16" thread. <S> This likely more expensive them getting the correct pedals. <A> You can't get an adapter to fit a big pin in a small hole, without pushing the pedals farther apart horizontally. <S> To keep the pedals at he same distance, you'd have to drill out the holes to a larger diameter and then rethread them, which probably isn't practical. <S> Just take the pedals back to the shop for a refund and buy pedals in the correct size (which is apparently 1/2in). <A> 9/16" - 1/2 <S> " crank adapters can be found online but do work out quite expensive. <S> Not an endorsement but an example of what to search for. <S> I notice the OP asked for adapters but considering the price and the fact with the adapters fitted your pedals will protrude further than normal
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, my actual suggestion is what others have said above and replace the pedals for 1/2" pedals to fit your crank.
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How to tighten v-brake pad without turning it out of position? I find it hard to tighten the hexagonal bolt of a v-brake pad without turning the whole pad out of position. I need to hold it in place somehow; I've tried with a big adjustable wrench, but it's still difficult (doesn't fit very well, and the pad is flexy).Why isn't a small part of the pad body hexagonal so I can hold it with a wrench while tightening? What's the proper way to tighten the pad onto the arm? <Q> I usually just grab the pad with my fingers, and carefully apply torque in the opposite direction of the torque I apply to the screw. <S> The two torques must be roughly equal (very roughly), if you apply too much torque to the pad, you are going to turn it the opposite direction. <S> It is not enough to grab the pad and try to hold it in place, you have to apply torque proactively to stop the first bit of movement before it happens. <S> Done right, you can tighten those screws very securely without rotating the pad. <S> Of course, you need to position the pads properly first, which is easiest to do by applying the brake, adjusting the position of the pads with the brake applied, and fixing their position by tightening the screws with your fingers. <S> You don't really need any torque at that point, as you are just fixing the position. <S> It's when you take out the wrench to tighten the screw for good that you need to apply the counter-torque to the pad with your other hand. <S> But, of course, a hexagonal surface to grab the pad with a wrench would be nice... <A> For that, it may help to have the brake cable temporarily adjusted for severe tightness: tighter than you'd be able to ride with. <S> (Once your pads are secured in place, then adjust the cabling to normal). <S> I've also simply held the pad with my other hand while tightening it, using it as if it were a tool handle. <S> It is not much smaller than the Allen key wrench; you can adequately supply the counter torque this way. <S> There is also a technique of getting it almost tight, such that it still allows a bit of rotation. <S> Then turn it into a position that is slightly off, so then it will rotate into place with the final tightening. <S> Lastly, a tool can be used to supply the opposite torque; for instance, you can restrain the pad between the jaws of a simple spanner wrench. <A> Apply the brakes while tightening the bolt. <S> The friction holds the pad in place and usually adjusts the pad so that it makes good contact with the braking surface. <S> If the pad still turns, try strapping the brake lever in the depressed position so that you can hold the break pad while tightening it. <A> I tend to get the pad where it should be, then tighten the fastener. <S> If the pad rotates on the last bit of tightening and I can't hold it with my fingers, then I push the tool in the other rotation, using my fingers to push as well. <S> This additional force will rotate the pad without significantly loosening the fastener. <S> Then tweak the nut tighter again. <S> Brake pads can be finicky wee things, and its both practise as well as technique.
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To tighten a rim-brake pad without it rotating, I've usually clamped down on hard on the brake lever with one hand to hold the pad against the rim, while tightening with the other hand.
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Mech disc brakes creating too much slack I've got a 2nd hand bike to play with as I've never been into bikes. When I got it the brakes only stopped while I wasn't on it. I stripped the bike down for cleaning and I re-attached the brake cable but the right lever is creating too much slack. I've tried creating more tension by pulling the cable through the housing and then tightening the cable but on release it gives too much slack again. <Q> Your actual rear brake looks like a electric scooter brake, I would ask whoever you got this bike from if they done any mods or maintenance on it. <S> 1st Image <S> Unfortunately I don't think any form of adjustment will get you any sufficient braking. <S> 2nd Image <S> You can see from the second image the different cable route designed for use on a bike, generally the cable is fairly straight from the nipple to the clamp. <S> Artek Vigourous brake sets can be bought for £25 a set front and rear. <A> I suspect there is something wrong with your cable routing. <S> The second picture in particular is indicative of this as the housing is arriving at the caliper at the wrong angle. <S> Inspect the cable route from lever to caliper, making sure the housing is properly inserted into the lever and caliper, and any frame attachment points. <A> It's not clear from your explanation whether the cable is slipping where it's attachedd or if the slack is coming from somewhere else. <S> I'm going to start with the former. <S> In your photo, the cable is pinched between the bolt head and the washer below it. <S> This setup has only a small flat surface area for gripping the cable, so it is easy for it to slip unless you tighten it so much that the cable is flattened. <S> The proper routing is under the washer. <S> The cable should lie in the groove that is just to the right of the washer. <S> The groove helps ensure that the cable is secure and pulling from the correct angle. <S> Disc brakes pull with a high leverage ratio, so it is easy to generate enough force to cause the cable to slide if it is not properly secured. <S> So, 1)loosen the bolt until the washer can be raised up enough to slide the cable beneath it. <S> 2) pull the cable taut. <S> Check that the end of the cable housing is seated properly at the brake lever. <S> 3) tighten the bolt while keeping the cable taut. <S> Make sure the bolt is very tight. <S> There should also be a pad position adjustment on the back side to adjust the position of the stationary pad.
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You may even need to move the lever arm slightly before tightening in order to get enough cable tension to brake properly. My suggestion is first find out if the brakes were replaced, and secondly if they were replaced which I suspect they're, you need to get the correct brakes installed for efficient and safe braking.
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Knee Pain - Injury or Out of Shape? I have been mostly lethargic for the past decade, sitting at a desk 16 hours a day. My brothers got me into mountain biking and it has been helping get me in shape. We've been doing it for about 2 months now. Over the last month, I've noticed that after each ride, I get more and more pain around my kneecap. There is some pain at the bottom of my kneecap, it feels like I hyper extended and pinched something, but there was no such incident that I can recall. It zapped me once while standing up doing nothing in particular after I had begin noticing it. I also have pain around the top corners of my knee cap. It feels like muscle soreness, but I don't think there are muscles there. If Google serves me right, that's where my MCL is. Both spots seems to just build up as I ride more and more. There wasn't any point where I had pain as though I injured either one at a particular moment, no fall, or anything like that. They just build up the more I ride. Both are about a 2 on the 1-10 scale, but persist all day. I don't know whether I should stop riding for a time, for risk that I did damage to something, and to let whatever it is heal. Or perhaps, on the other-hand, if riding just requires my knee to "get in shape", and this kind of pain is to be expected while my joints get used to being used again. I've made sure my position is as right as I can. Has a few people inspect how I right, and also had a few shop keeps look at me too. Everything seems set up right. I extend my leg to where is is just bent a smidge for my saddle height. I've got the pedals under the middle of my foot. Any insight? Is this to be expected or am I injuring myself by continuing? More info - I'm 43 with no past injuries. They always have creaked a little more than my peers. Both knees hurt equally, although the right knee def more towards the top of the knee cap while the left is around the sides and bottom. The best I can tell with measuring tape, my legs are even length. <Q> Is this to be expected or am I injuring myself by continuing? <S> You're probably injuring yourself by continuing. <S> It sounds like your bike is set up reasonably, so you should probably seek out a sports physiotherapist. <A> I'm gonna start with the standard disclaimer: <S> Don't take medical advice from random strangers on the Internet! <S> That said, you might investigate patellofemoral syndrome ; one common cause can be over-training of the quad muscles relative to the other knee muscles (in particular the hamstrings). <S> This over-training is something that's fairly easy for a new cyclist - who probably isn't clipped in and is cycling with a pure pushing motion - to develop. <S> A physiotherapist can help both with diagnosis and treatment. <A> You're describing an overuse syndrome that's causing acute inflammation involving the soft tissues of the knee. <S> As the knee joint flexes and extends repetitively on a bike ride, the tendons, ligaments, cartlidge, and tough, fiberous fascia that encapsates the joint encounter forces and friction <S> they're unaccustomed to. <S> The sliding of these tissues against each other and bony prominences create friction. <S> This friction causes an inflammatory response in the affected area, nerve endings within the inflamed area register a pain sensation. <S> Tendons and associated fascia are particularly vulnerable due to greater forces and greater movement of these structures occur. <S> Tendons connect muscle to bone, store-up and release a good deal of elastic force created by muscle contraction and have a relatively large amount of movement when compared to ligaments, cartlidge and bone. <S> So as the knee joint goes through it's natural range of motion---under the tension of pedalling---these tissues are sliding against each other, eventually with enough repitition to inflame and hurt. <S> There is a degree of tolerance that develops as physical fitness develops. <S> However, what you describe is more acute inflammation and should be addressed on multiple fronts. <S> A few things you can do today: <S> ice down the knee joint. <S> No need to freeze your knee as a reusable cold pack wrapped in a towel and molded around an aspect of the knee joint will deliver ample cold therapy to the joint. <S> Use of NSAIDS, such as ibuprofen, naproxsyn, or aspirin, if not contraindicated by other health issues typically involving the stomach, bleeding problems, or heart conditions where anti-platelet therapy is being conducted. <S> The goal is to reduce the inflammation and rest is the key ingredient for that. <S> I don't mean be sedentary-- but stay off the bike for a few days. <S> After the acute phase has passed--evident by little to no pain throughout the full range of motion--begin biking again slowly. <S> Fewer miles or minutes with good technique. <S> A big thing I would focus on is pushing lower gears at relatively steady 80-95 rpm. <S> This involves using your gears more often than you'd think. <S> Spinning it's called. <S> Ease into it while you obtain these specialist evaluations and your form and fitness improve. <S> Good luck. <A> I've got the pedals under the middle of my foot. <S> Try putting the ball of your foot over the pedal spindle/axle, IE slide your foot backward a little. <S> This effectively lengthens your leg, so you may need to raise your saddle 5-10 mm to compensate. <S> This will encourage your shin muscles to do some more work, and may help. <S> On the flip side, your knees are already sore and it may be hard to detect improvements and changes while they are inflamed.
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Muscle soreness is to be expected when you increase your exercise load, but exercise shouldn't cause joint pain.
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WTB Horizon 47c - small crack in the middle of the tire I’m headed off on a 3 week bike trip and just now noticed a small hole in the middle of running tread of my front tire. I have a few more days before heading off into a more remote area and wanted to know if this is something I should take care of beforehand. The tires are WTB horizon 47c’s and I’m running them with tubes. Attached is a picture of the crack Thanks! <Q> One of the go-to sites has this to say : "Cracks in the tread are harmless. <S> Small punctures in the tire such as are typically caused by nails, tacks, thorns or glass slivers are also harmless to the tire, since the tire doesn't need to be air-tight." <S> I commute daily, and by the time my tires are about half way through their lifespan <S> there are dozens of minor gashes like that in the tire. <S> You just want to check that there's nothing lodged in there that will work inward and puncture your tube. <A> This type of cut is quite expected on tyres and usually nothing to worry about. <S> Its caused when something (a small stone, shard of glass etc) cuts the rubber, but is stopped short of causing a puncture. <S> Carefully ease the cut apart with your fingers and see if you can see the inner tube. <S> If you can see the tube, the tyre needs repairing from the inside. <S> If you can't see the tube, the casing is intact and you can continue to use the tyre, although some people like to use superglue to close these cuts to avoid more debris finding its way in <A> Can you see your innertube from any angle, through the hole ? <S> If so, expect it to puncture every couple hundred kilometres. <S> Source, personal experience. <S> Since you're going on a long remote trip, it would be wise to pack a spare tyre for each different wheel size in the group. <S> how much spare stuff you want to carry. <A> There is nothing to worry about this, that probably was a puncture in the past or a near-puncture. <S> I have used a bike having tires with damage larger than this. <S> If you remove the tire and look at it from the inside, if the inner structure of the tire doesn't have a large hole, you are fine. <S> If it does, install adhesive high pressure cloth rim tape on the inside of the tire to prevent the inner tube from being visible, and closely monitor the area for any bulges. <S> The times to replace a tire are when the sidewall is damaged, or you see a bulge in the tire, or the tread is so worn that the cords start to be barely visible (except on a mountain bike you probably want to replace earlier than when the cords become visible, because a MTB requires the traction on mud that tread pattern gives you). <S> Until that, to save your money, it's repairs and not replacement. <S> By the way, have few spare inner tubes, a spare foldable tire, patch kit an tools to remove and install a tire with you at all times during the bike trip.
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One fix is to slap a tube patch on the inside of the tyre, to act as a boot and prevent the tube from herniating out through the hole. Spare tubes are a given, but it really depends how far from support you're going to go as to
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What explains 9 speed cassettes price differences? I have a pretty heavy bike I use to travel long distances with a lot of luggage. It has a mix of XT, deore and other Shimano equipment. I bought it second hand so I don't really know the details. I have ridden 10,000km with it without replacing anything in the drive train, and it's now so used up the chain skips when I apply too much force on the pedals, and my foot just goes straight to the ground. I want to change the 11-34 cassette and the chain to solve that. On the website I will order from, they have: a 14€ HG400 Alivio Sora a 16€ HG201 Acera a 47€ M770 XT I have no idea what explains the price difference. As far as I can tell they are all compatible with my XT derailleur but the XT one is lighter. I don't really care about weight as I use this bike to transport heavy equipment anyway, but I do care about durability. What should I buy? Should I also change the rings at the same time? Thanks a lot for your help. <Q> In most cases with bicycle parts, more expensive means lighter. <S> There can be exceptions, especially when you get to the super low end parts where cheaper can also mean cheaper construction. <S> Since you put so many miles on your bike and it seems important to you, I would spend the extra 2 pounds and grab the Acera. <S> XT is generally used on mountain bikes where weight matters. <S> If your cassette and chain are that far gone, your chainrings are as well. <S> You will get terrible chain suck the minute you put a new chain on. <S> You can avoid needing to replace the cassette and chainrings by periodically replacing the chain before it gets too worn. <S> Invest in a chain wear checker, they are cheap. <S> Replacing your chain periodically will save you a lot of money! <A> (Road will be around 11-28, MTB 11-34). <S> The way I buy cassettes is decide a price point and look for something being sold at the biggest discount, so I aim for great value for my money. <S> Don't limit yourself to $himano, brand does not usually matter with 9 speed cassettes. <S> At the price point of Acera/Alivio Sunrace and Microshift probably give better value as this is their target markets. <S> If you have done 10000km on the same drive train, you really need to replace the chain rings as well. <S> These will be worn and will wear the new chain, and therefore new cassette prematurely. <A> I have no idea what explains the price difference. <S> Well, basically: quality of materials and construction. <S> Lighter weight, stronger materials are more expensive. <S> Better designs tend to be more complicated which means more manufacturing steps at higher precision, which costs more to execute. <S> There's also demand and what consumers in the market will pay. <S> For bicycle components it seems some people will pay exponentially more for incremental improvements in function and quality. <A> It is rumored that the god father of Mountain Biking Keith Bontrager once stated that components have 3 characteristics cheap, light and durable. <S> The problem is you only get to pick two. <S> The low end of a component line tends to be relatively inexpensive but also likely to be heavy. <S> The top of the product line tends to be the most expensive and the lightest but not the most durable. <S> Pro riders are more concerned with weight and performance than durability. <S> Most sources will tell you the best bang for the money is the product tiers one or two levels below the top tier line. <S> For a Road Group this is likely Shimano 105 and Ultegra. <S> A similar Mountain Group would be SLX or XT. <A> XT cassettes are a slightly different and more complicated design. <S> The large sprockets are on a nice aluminium carrier for lighter weight. <S> Unfortunately this means they're not as strong - we folded one on our MTB tandem. <S> We've not broken a cheaper one. <S> So I'd buy one of the cheaper ones. <A> This was initially thought to be a comment, but then I realised none of the questions covered the confusing part of the shown prices. <S> Generally Alivio is higher in the product hierarchy than Acera. <S> With Shimano you can go by the first digit in the product name to get the tier. <S> So based on this the HG400 is better than the HG201. <S> Better as in higher quality materials, lighter weight and probably better workmanship (a. i. better precision). <S> However, you can see that the better part is cheaper than the lesser one. <S> Prices sometimes fluctuate based on stocks (old models) or special offers, so some higher tier components can be had for less than lower tiers in the same shop even. <S> It's not an uncommon thing to find this kind of price inadvertence, so I think this is what you see here. <S> Even without the very good deal you have in front of you <S> I think the HG400 marks a sweet-spot in price/quality. <S> It's what I myself buy for my bikes, when I try to keep the budget low but don't want to compromise too much on quality and reliability.
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You will get near top tier performance at a cost savings at the sacrifice of some extra weight. Most importantly: Absolutely replace your chainrings! XT will shift a bit better and be lighter, but probably won't last any longer. The difference between the Sora and Acera is probably down to largest cog size - on MTB sets its larger.
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Why does Fox specify to fix the lever in an upright position, on a Rhythm 34 fork that uses a Through-Axle? I vaguely remember that "conventional wisdom" states that closed QR levers on MTB forks should point towards the back of the bike (see Which direction should QR lever point? or What is the proper position for quick-release levers? ). However, I just saw that Fox specifies something different from the anwers to these questions in the manual of the Rhythm 34 thru-axle fork: "The closed lever position must be between 1-20 mm in front of the fork leg.", i.e. like this: Out of curiosity: Why is this so? Would it be harmful in any way if I ride with the lever pointing backwards instead of upwards? Source (image and quote): Fox manual https://www.ridefox.com/dl/bike/605-00-136-34-Tuning-Guide-revC.pdf <Q> Most likely the manual writing team knew they had to specify a 'safe' QR position so the company would be covered legally. <A> Generally I'd put a QR lever at an angle close-to a frame tube but absolutely not touching the frame. <S> The main purpose is to stop the QR lever being opened or loosened by any sort of foreign object. <S> That may be another rider's wheel/tyre, a stick or road rubbish kicked up and catching wrong, or even a lucky catch on live foliage. <S> One difference is that's all about QR levers for QR skewers, where one flip of the lever leaves the skewer quite loose and retained just by gravity and lawyer lips. <S> Your quote is about a through-axle / thru-axle, where flipping the lever generally does not start any sort of disengagement. <S> Instead you have to unscrew the axle with that lever. <S> So in theory the lever could be closed or open without issue other than marring your paintwork or possibly catching on grass or maybe spokes (unlikely). <S> As long as the QR or TA lever isn't being rotated, and was closed to the correct torque, then the lever could be at any angle provided it doesn't rub or catch. <S> One later thought - the recommended distances could be about east of un-doing the lever. <S> I remember having to use an extra lever on a super-tight QR that was fitted to fork dropouts through a bare hub, ie without a wheel built on the buh. <S> If OP's TA lever was pointing forward or backward, the rider may be tempted to push on spokes or on the nearest piece of rim. <A> My guess is that is the reason for this particular lever.
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Some QR levers won't close all the way if they are impeded by the frame/fork. In consultations with the engineering and legal team they decided that in front of the fork leg was the safest position, or at least the position that a company lawyer could defend as the safest position in the case of a lawsuit.
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Installing a chainguard on a bike with derauiller My pants always get caught in the chain (and wearing shorts is not an option). However, it seems that it's impossible to have both a derailleur and a chainguard so what is the solution? Can I just lock the front derailleur in place and slip the chainguard past it. (locking the bike in top gear?) Do I have to remove the derailleur entirely, by breaking the chain? Can I just remove the smaller front gears and lock it into third? How difficult is this? Do the gears just pop off or is there more to it? Does anyone make a metal chainguard so large that it could encapsulate both the derauiller AND the front crankset. (a preferred solution, but not easy to find) Example of a chainguard to protect the pants from getting ripped. It also proctects the rider in case of a fall so that the gear teeth don't puncture the leg. (It happened to me and is just as nasty as it sounds! Gear teeth are dirty.): Note: The winning answer will suggest a chainguard that covers both the top of the chain and the crankset (as seen in the picture above). Suggestions of tying, clipping or banding pants are not an answer to the question being asked. However, an answer that involves modifying the bike in some way to accommodate a chainguard will be accepted. <Q> This StackExchange site has its limitations, in that product recommendations are not allowed because of regional differences and products/pricing going obsolete. <S> However I think the answers are no <S> you don't have to break the chain, remove the derailleur or lock off any gears. <S> Products exist but are quite unusual so you will have to do some searching online or in bike shops in your local region. <S> Using Google, I found a couple of examples. <S> The first one I got to a website which sells chainguards and browsed through the ones which say compatible with a single gear, and discovered some which say compatible with a triple ring like this style: <S> Another Google search along the lines of "chainguard triple derailleur" and I found this image, which has a more conspicuous allowance for the derailleur to remain fitted and usable: <A> In a way, the front derailleur already is a sort of chainguard device as it restricts chain movement. <S> A correctly set up front mech makes an extra chain guard redundant, and clutch devices found in modern rear derailleurs that control chain tension <S> even more make it even less needed. <S> Standalone chain guard devices are mostly needed for two reasons, and predominantly in more technical mountain biking disciplines such as enduro and downhill, where chain really flies like crazy: <S> The bike is a 1× system with a single front chainring, thus no front derailleur. <S> The chain guard is combined with a bash guard device meant to protect the front chainring from rock strikes. <S> It is unclear what type of chain guard you are trying to install, please clarify, but <S> the most common type these days looks like this, and it is certainly not compatible with a conventional front derailleur: <S> There are however other types of chain tensioner devices, both DIY and commercially solved, that would allow you to reduce chain movement while being compatible with a front derailleur. <S> E.g. from here : <S> Or something like a small red wheel below the chain on the picture below. <S> Here you also see a 2×-specific bash guard mounted to the spider: <S> Can I just lock the front derailleur in place and slip the chainguard past it. <S> (locking the bike in top gear?) <S> Do I have to remove the derailleur entirely, by breaking the chain? <S> Do I have to remove the smaller front gears? <S> Is this possible? <S> All these options suggest that you want a single front chainring. <S> It is possible, but will most likely require upgrading the whole drivetrain, including rear derailleur and cassette (not a cheap way), or tinkering and making compromises with existing drivetrain (requires a bit of a knowledge or time). <S> Having a single front chainring opens some options for installing a chain guard. <S> Keep in mind frame compatibility issues: you cannot install an ISG-typed chain guard on a frame that lacks mounting tabs for it. <S> Unless you absolutely cannot allow a chain drop, you won't need a chain guard in such case. <A> The (imperfect) solution for derailleur systems is a protector ring, which is also called a "chain guard" . <S> Though it's missing from your crank set, chances are that a matching guard does exist; look into it. <S> See those four empty bolt holes near the outer circumference of the large chain ring? <S> That's where the chain guard is attached. <S> Basically it just has to have the right bolt circle diameter, and overall radius. <S> If you have that type of chain guard, and also do something to bind your loose pant leg to your leg, you shouldn't have any problems.
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However, a modern combination of a so called narrow-wide single front chainring (seen on the first picture above) and a rear derailleur with a clutch device is enough to retain the chain on their own.
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Why are road bikes (not time trial bikes) used in many triathlons? I've been watching triathlon videos lately and I couldn't help but notice that, with the exception of Ironman Competitions , only road bikes and not time trial bikes are being used. Is there any reason for that? <Q> The OP linked 4 videos, the first 2 videos were long-course Ironman races, where time trial (TT) bikes were used, while the latter 2 videos were of short-course draft legal races where road bikes were used. <S> In the latter two videos the competitors were either pros or elite amateurs. <S> These individuals typically have multiple bikes and would be using a TT bike if it was the right tool. <S> Originally, all triathlons used to have a no-drafting policy, which made optimizing your personal aerodynamics critical. <S> Hence the rise of TT bikes in the early history of triathlons. <S> Relatively recently drafting has been made legal in many short track triathlons, making TT bikes both dangerous and not suitable for the format. <S> When you have drafting you essentially have a road race, which a road bike is the right tool. <S> Quick handling is key as you need to be able to maneuver and keep your front wheel within 2-6 inches of the bike you are drafting in order to get the full draft effect. <S> Groups can at times move incredibly fast, 65 kph on the flat is not uncommon for pros or elites. <S> In contrast, Ironman events still have no-drafting rules in place making TT bikes the right tool as its about individual riders against the wind and not responses to group dynamics. <S> NOTE: <S> the answer is intended to address the races explicitly highlighted by the OP, not all world wide triathlon events, nor the large array of amateur races where participants may be balancing a number of considerations (e.g., cost). <A> Triathlon and time trial bikes are quite expensive and not wonderful to ride on open courses, hills, and in groups (in other words, general cycling). <A> In addition to Paul H's answer, there are several different triathlon distances from sprint to full iron man. <S> In shorter races with hilly bike courses, or where there are many tight turns a regular road bike may be preferable. <A> Another lesser point is money - sport costs, and a triathlon is essentially three distinct sports in one. <S> For some competitors, that will also be their commuter come Monday morning. <S> I've even seen Mountain Bikes used in a triathlon, with road tyres and locked out suspension. <A> My own observations do not agree with yours. <S> In the Gulf Coast 70.3 this year there were a fair number of people on road bikes and even some on hybrids. <S> There was one lady with a basket on her bike. <S> This past weekend, and many event like it, I attended an event where a <S> they had a Sprint that had and Olympic distance at the same time through MultiRace. <S> As usual there were many high end triathlon bicycles. <S> Despite it being a no draft race, a road bike might be more suitable as the roads are really rough. <S> It makes it difficult and possibly dangerous to remain in aero the whole time. <S> If you go to just about any event you will see a full spectrum of bicycles. <S> Many, for cost reasons do like I did and have a road bike with clip on aerobars. <S> Its very cost effective. <S> Finding a used road bike is far easier then finding a used tri bike.
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So, if you're not so serious about triathlons that you're willing to spend several thousand dollars on a bike that will see relatively little use, you'll likely be content with your existing road bike whose handling and fit works well with your body and riding style. The bike is an expensive item, and so making use of what you have is a perfectly good solution. You also need to be able to accelerate, brake, and change direction quickly to close gaps and respond to group dynamics.
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What tool to adjust brakes My brakes make a noise on a time interval, as the tire rotates around. I have Shimano BR-MT520 brakes. I hear you can loosen the two bolts and move it side to side to adjust. What is the name of the tool and what size do I need? <Q> Shimano BR-MT520 <S> brakes are hydraulic discs. <S> The alignment can be adjusted by loosening the two mounting bolts. <S> The bolts typically have Torx T25 size heads, so you need a basic T25 wrench at least. <S> If your rear caliper is mounted between the seat and chain stays the bolts can be difficult to get to, so a L-shaped rather than <S> a T-shaped wrench is necessary. <S> The basic short-cut technique for aligning the calipers to loosen the bolts <S> so the caliper can move but is not loose, pull the brake lever hard, tighten the bolts. <S> See this Park Tool page for more details on caliper alignment. <S> They can be straightened fairly easily. <S> See this Park Tool video . <S> Update: <S> I read through the BR-MT520 <S> Dealer Manual <S> and it seems the mounting bolts are in fact 5mm hex heads. <A> You need a set of metric hex wrenches, also called allen keys, hex keys, and allen wrenches. <S> They are hexagonal in shape, and come in sizes from 1.5 mm (maybe smaller) to 10 mm (maybe larger). <S> Your local hardware store will have an appropriate set. <S> For bike maintenance, I recommend getting a set that covers 3 mm to 10 mm. <S> The 4 mm, 5 mm, and 6 mm keys will be the ones you most often use. <S> Your brake caliper can be adjusted with one of those (my guess is the 6 mm). <A> The BR-MT520 utilizes size M6 caliper fixing bolts to secure the brake body to the bike. <S> M6 bolts have a hex key hole in the head for the hex key (aka: Allen wrench) to fit. <S> This hole is 5mm wide on an M6 bolt and therefore you'll use a 5 mm hex key to loosen and tighten it. <S> (As an aside, the 6 in "M6" refers to the width of the threaded portion of the bolt which is 6mm in outside diameter. <S> A metric socket head cap bolt like we're dealing with here accepts an Allen key that is 1mm less than the "M"# of the bolt). <S> To center your caliper to the rotor, loosen both of these caliper fixing bolts and squeeze and hold the appropriate brake lever. <S> Snug the bolts back up enough to "fix" the caliper in position, release the lever and rotate the wheel to check that there is pad clearance of the moving rotor (no rubbing). <S> If that fixes the intermittent rub, finish by fully torquing the fixing bolts to the spec'd 5-7 Nm. <S> If a rub is still present, you can retry the above with both bolts and another technique is to alternate the loosening of bolts (one at a time, squeeze lever, snug up the single loosened bolt and check for rub after each bolt). <S> One thing that needs mentioning is that the VERY FIRST thing you should check when confronted with intermittent wheel noise is that the wheel is fully seated and properly secured in the dropouts. <S> Less of a concern with thru axels but check the symmetry and security of the hardware in this case too.
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There are special tools for this but an adjustable wrench works reasonably well. If your pads are rubbing periodically as the wheel spins, your rotors are probably warped.
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Tape or grips for bar ends? I've just added a pair of bar ends to my handlebar. I feels surprisingly good, except that they are too thin, compared to my grips. Are there any options to make them more comfortable? Maybe I can put a bar tape on them? If so, should I look for some specific type of this tape? This is a picture of them if it helps. <Q> Adding bar tape to the bar-ends is certainly possible. <S> What kind of tape you want to use is determined by your preference. <S> There are both thin and thick types available. <S> If the bars still feel to thin after applying a layer of tape you can try double-wrapping them. <S> Drop bars are wrapped from the ends towards the stem, with the starting end of the tape tape tucked into the end of the bar, secured with the end-plug. <S> The other end is simply secured with tape. <S> Direction of wrap is important, force from the hands tends to be downwards on the outside of the drops section of drop bars, so you will want the direction of wrap to be downwards on the outside also. <S> This Park Tool video may help you. <A> I have added standard grips to bar-ends for some added comfort. <S> Depending on the grips they can be difficult to pass over the bend. <S> They are shorter and tend to be less expensive. <A> I've taped some bar ends successfully using cheap bar tape. <S> Apply heat from a hot air gun <S> and it closed up nicely holding but not compressing the tape. <S> At the end, there was enough heatshrink out the front that it was unsupported and shrank so I could shove the excess into the barend with a finger. <S> As a last step I put the bar plugs in place, and it works well. <S> As you can see, I had janky red foam bartape from China, cost around $2 a roll. <S> It works fine and is thick enough for comfort, but is not very abrasion-resistant, and the red fades to pink quickly. <S> A <S> ~130mm length of 35mm heatshink went over the outside fine. <S> The silver bar plugs are tamped in the end. <S> This one shows a flat bar that has been given the same treatment. <S> Bartape first, then a layer of heatshrink. <S> This photo shows how the outer end shrinks the most, and then gets tucked into the hollow end of the bars. <S> Barplugs would make this nicer and safer. <S> Finally this shows another use for the heat shrink. <S> Here's a pair of cheap nasty grips that have gone gummy or tacky. <S> The rubber is breaking down and they should be replaced. <S> But some 45mm heatshrink on top will conform to the outer shape and produce a nicer surface to hold. <S> Do note that concave features may not work as expected unless there's room for pull-down from adjacent areas. <S> You can also buy heatshrink with a heat-activated glue lining to help, but I've never had success with that. <S> Lastly - here's some heatshrink used on the bottom of some drops. <S> I don't currently have any bike with this at the top/stem area. <S> This was just to retain the bartape in addition to bar plugs, not to cover it all. <A> So as @mikes suggested I've used a pair if standard grips. <S> Before that I've tried to use a hockey tape, but it was not tight enough and could be easily twisted by hand. <S> To put grips I've had to use some lube on it - otherwise I could not pass through the curve on bar ends. <S> This gave me more comfort since grips absorb little vibrations and are not so cold as the bare metal.
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You may have trouble getting thick tape into the end of the bar-end as they are of somewhat smaller diameter than drop bars. Heatshrink is also available in different colours, if you're feeling snazzy. I used grips designed for Twist Grip Shifters. As a second stage I used a length of 30~35mm black electrical heatshrink tube over the top of the padding tape.
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Help please - I am suspicious this bike might be stolen I recently got this Btwin Triban 3 bike from a person I definately trust. He said they have had it for a couple of years but don't use it anymore and originally got it from a family member a while ago. Also it needs work (flat tyres, rusty chain e.t.c so it's not really rideable). However I noticed that the sticker on the bottom that all btwins have has been scratched by probably a coin, where the number/code is found which to me seems suspicious.Also, I checked the serial number which is stamped into the frame on www.checkthatbike.co.uk and the results "couldn't find any identification the bike is stolen". On that basis, If I decide to sell it would that be ok and would I have to take anything else into consideration?Many thanks in advance <Q> No one can ever be certain a bike has not been stolen, unless they bought it from the shop. <S> Not all stolen bikes are reported, and not all owners of reported stolen bikes know the serial number (many would struggle to remember the colour, let along make and model). <S> I cannot comment on how diligent the authorities are in you location at loading the serial numbers into the database if they are provided, but in most jurisdictions, bicycle theft is not placed particularly high on the 'worst crimes' lists. <S> A hit in the database means its is almost certainly stolen, and the burden of proof would be on you to prove its not. <S> A miss in the data is exactly that - a miss in the database. <S> It means nothing as to the legal status of the bike. <S> The database miss, intact serial numbers and the history you have been told, give you reasonable grounds to believe you have legal rights over the bike and are free to with it <S> what you like. <S> Should it turn out to be stolen, you would forfeit the bike, but it would be unlikely further action would be taken against you (depending how cooperative you were feeling). <S> (Where I live <S> the Police seem to drive around to the thiefs house, pick up the bike and call it a good days work. <S> I suppose if they keep tabs on the crooks rather than shutting them down, they know where they can go to collect peoples stolen bikes). <S> As far as the bar code - looks to me like the damage is simply the cables rubbing - maybe in a carrier or work stand, or maybe when the bike was being washed. <S> Personally I take those things off, even though you don't see them, they look cheap and ugly. <S> The state of the label is absolutely nothing to be worried about. <A> <A> btwin is a decathlon brand - you could try registering the 30 digit serial number at https://www.decathlon.co.uk/register-your-bike.html <S> Given the length, its probably the barcode number, not the one stamped on the BB shell. <S> Downside, it requires a "decathlon account" as well, and may not work if the bike has been registered to a previous owner.
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There is another site you can run the serial number from bottom bracket to check if it was reported stolen.... https://bikeindex.org/serials Morally you have done everything practical to ascertain its not a stolen bike, nothing more can be done.
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Are more expensive chains/casettes more quiet? If we ignore the lower end products and compare mid and high end products. Is there a noticeable difference between the sound produced while pedaling in the same gear (Not the shifting sound)? For example if we are talking about shimano, compare tiagra or 105 vs ultegra or durace. This question is not so much for road use but to use the bike in a trainer inside a flat. <Q> I think a well-adjusted, modern system from any of the major players in components will be reasonably quiet and generally the same volume level. <S> The trick is to make sure your cable tension, limit screws, and derailleur alignment are tip top. <S> But that's true even if noise isn't an issue. <S> In your case, I would guess that your trainer will be much louder than your drivetrain. <A> If the chain and sprockets are clean, properly lubricated and not excessively worn there <S> probably isn't very much difference in the level of sound coming from the drivetrain. <S> they also transmit a lot of vibration into the floor they are sitting on. <S> If used in an upstairs room they can project a lot of noise into the room below. <S> Obviously this would be bad in an apartment or flat. <A> The difference in chains and cassettes as you go up the price range <S> is primarily weight saving and slick shifting. <S> The noise that it makes is no different. <S> The chains all come waxed so they're lubricated optimally and quiet, and the cassette has no impact on noise. <S> higher end stuff will shift quicker and smoother, but that's a small amount of noise. <S> As noted by others, the main noise is from: <S> The trainer <S> The wheel rotation <S> So the trainer is a resistance unit, the noise mainly comes from the contact of your tyre on the roller/resistance wheel. <S> Make sure you use turbo specific tyres for wear, grip and noise reasons. <S> Then it's the noise of the magnets/motor/resistance set up. <S> Plus the vibrations of the motion transmitting through the frame. <S> Combined with the noise of your wheel <S> /spokes cutting through the air.
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A well adjusted drive chain will shift smoothly without noise, the clicking when it's not shifting well is generally from poorly adjusted drive train. Some indoor trainers make far more noise than the actual bicycle.
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What features does a mountain bike need to be converted to an ebike? I'm looking convert a mountain bike and convert it to electric with a rear hub kit. I am wondering what features I should look out for to make this easier: Is there any way to keep the cassette that comes with the bike or does this have to be replaced? Does it matter if it's a "freewheel" or "freehub"? Will the front crankset need to be replaced with a larger gear for the higher speeds? Currently looking at a bike with a 40t large gear. Does it matter which brakes and shocks come with it? Do mountain bike tires work well at higher speeds or does it make sense to get something less "stubby"? <Q> The cassette and hub will depend entirely on the conversion kit - is it a front wheel, rear wheel or center drive? <S> If rear wheel, you probably will replace the whole wheel with a choice of swaping the cassette over or buying a new cassette. <S> It might not be possible to install a 40 tooth chain ring on some modern mountain bikes. <S> While the 3x bikes of yesteryear regularly ran 44, its rare for a MTB today to run bigger than 38, and 32 or 34 is most common. <S> The frame designers are probably not considering large chain rings as an important feature in the difficult and crowded area around the BB (on Soft tails). <S> You would need to check the frame to be sure. <S> To me, the main consideration is the ability to put an interrupter on the brakes, that cuts the engines when the brakes are applied. <S> This means you will need E-Bike specific hydraulic brakes (Most E-Bike kits have levers for cable brakes with a switch built in). <S> There are after market adapters for hydraulic brakes, but they reply on a stick on magnet and switch. <S> Knobbly MTB tires work best on soft conditions, slicks on smooth pavement. <S> The E-Bike aspect changes nothing. <S> (Keep in mind an elite rider can probably output more power than a weekend warrior with a 500W motor). <S> Install the tires that suit the trails you ride. <A> Frankly, this question is too broad. <S> You need to research what's out there <S> and what other people have done, and this is not the place to do it. <S> Read up in places such as endless-sphere.comAnd be realistic with yourself about how you will use it. <S> To attempt to answer your specific questions: it depends on whether you go with a rear hub motor, front hub motor, or one that mounts on the bottom bracket. <S> same as above, and also depends on how fast you are planning on going <S> / will the bike be pedal assist? <S> Throttle only? <S> A combination? <S> Also note that most jurisdictions have laws regarding the maximum speed of ebikes. <S> brakes and shocks? <S> Depends on the type of riding you will be doing. <S> Is it all going to be on nicely surfaced roads? <S> (do you need shocks at all?) <S> On mixed terrain? <S> Will you be riding in wet conditions? <S> (Maybe disc brakes would be a good idea...) or fair weather flat roads? <S> (V-brakes are probably fine?) <S> Don't waste money on cheap suspension. <S> You'll be better off with none in most cases. <S> Not sure what you mean by "stubby"... large blocky tread? <S> Are you going to ride on pavement? <S> Gravel? <S> Mud? <S> You will need to research what fits your needs. <S> Do you want a steel frame? <S> 8-/ aluminum, carbon :-( <S> There's a lot more <S> you will need to research to come to an initial conclusion (speaking as someone who has done it... good luck) <A> New point - added weight. <S> No matter what you do, adding a motor will add the weight of the motor, wiring, batteries, and controller. <S> In a modern lithium-something battery this will probably be below 10 kilograms, but that's very roughly doubling the standing weight of the bike. <S> It will feel different with that change, more-so if you mount the batteries high up. <S> I suggest you buy the bike you want, <S> don't look to mod a brand new bike. <S> This helps overall weight distribution. <S> A retrofit kit might use up a bottle cage mount which isn't good because as noted, batteries are heavy and two little M5 bolts are barely up to the task. <S> Other retrofit kits include a carrier/rack and locate the batteries high over the rear axle. <S> This is particularly sub-optimal because the added weight is 100% on the rear, which is moving the balance away from the 60/40 ideal. <S> TL:DR <S> ; get the ebike you want - buying a bike to retrofit an electrification kit will result in a poorer bike than one built to be electrified. <S> Rephrasing that on the question - look for a bike that lets you mount the batteries inside the frame, or in a properly secured way that is low on the frame. <S> Not a bottle cage mount, and not a rack mount. <S> Downside - they don't exist, so if you want an ebike, buy an ebike.
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Get tires that are appropriate for the riding you will do. A new ebike would have the batteries placed inside the downtube, or aft of the seat tube. No one off the shelf MTB is going to fit the mold for whatever it is you want to do.
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Adding gears to my grandson's 12" bike My grandson has the kind of bike you pedal backwards to brake, and he goes riding with me on my days off. Yesterday, he asked me if we can convert his bike because we have looked everywhere and no one seems to have a gear-shifting bike for someone who is 8. The Problem is that he is having trouble keeping up with me and wearing out a lot earlier because of the hills. Are there bikes with 18" or less wheels that shift or is he still too small for that kind of riding? I am pretty sure that I can figure out how to mount the gears and get a small derailleur just to learn how to shift and I am pretty sure I can change his brake system to the handlebar levers, but not sure it would be so wise, if I could just get his parents, who are willing and more financially able, to replace the bike with one that is built to be a dirt bike and not a trick bike frame with attachments to help him go faster. I am pretty sure it is possible and I may even be able to make it just like mine but not sure how cost effective it is if he can just buy one. I am still learning what different bikes are called. But he is about 3ft tall and his bike is getting too small for him. His current bike has 12" wheels. <Q> It may be that it's your expectations, not his bike, that should be modified. <S> It seems really unlikely that you could retrofit a derailleur onto his current bike. <S> A frame that small won't have room for a wider rear-wheel assembly. <S> Even if you did succeed, he'd still be driving it with eight-year-old legs and an eight-year-old's heart and lungs. <S> Might you consider a tagalong bike , mounted to your bike? <S> Your grandson might balk at this if he's used to his own separate bike, but it would ensure that he keeps up with you. <A> Is he extremely short? <S> An 8-year-old is almost 9 years old, and: "26 inch mountain bikes are suited for kids that are 9-13 years old. <S> " <S> Don't fix up the 12 incher. <S> Head into a local bike shop and get a proper sizing. <A> If you are absolutely set on converting the bike, use an internal gear hub (IGH). <S> There are IGHs with three gears (the usual kid's first IGH), and there are IGHs with seven gears (suitable for many adults), and both of them are cheap when bought second-hand. <S> The last IGH I bought was a seven gear with coaster brake which I got second hand for 25 Euros from my local bike shop. <S> The main cost factor (either time or money for labor) will be rebuilding the wheel with the new hub. <A> Like cmaster mentioned, fitting internal gear hub (even 7-speed) wouldn't be too difficult. <S> It would consist of: <S> Rebuild the wheel around the internal geared hub. <S> For a light-use bike, spoke tensiometers and such advanced tools are not mandatory. <S> Route the gear shifting cable from back wheel to handlebar. <S> I guess you could zip-tie it, if you don't find any better method of mounting it. <S> Install gear shifting lever on handlebar. <S> But if you are aiming for the granddad-of-the-year award, install a front wheel e-bike assist motor also. <S> That will make uphills a breeze. <S> The common cheap kits would probably work, though you should pick one with lowest powered motor and smallest battery to avoid adding too much weight. <A> Adding gears to an existing bike will likely cost more than a decent used bike and will not likely end up problem free. <S> I have an 8 year old <S> and we just got her a new bike with gears, we live in an area that is quite hilly. <S> She has a 24" hybrid bike (road tires with upright seating) with 14 speeds and grip shifters. <S> We've gone as many as 12 miles with hills and she has no problems keeping up. <S> 24" may seem big, but the seat on her bike is almost the same height as the tire.
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Mounting rim brakes would be tough if the frame isn't already set up for it. This is possible to do at home with basic equipment, takes a few hours to learn but in my experience is quite easy and there are many tutorials online. If your grandson is that young, he's likely to have trouble keeping up with you no matter what bike he's riding. I think your best bet is buying a new child's bike off Craigslist, one with gears.
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On what surfaces can I safely use my hybrid bike? I will be doing a 50 mile ride in a few weeks' time, most of which is on tow paths and a disused railway line. The surface will therefore be somewhat rough and loose, but not muddy and no major obstacles. Obviously I would like to use the bike I have, which I use for commuting every day on smooth tarmac bike paths.It is a hybrid bike (rigid forks, flat handlebars, regular rim brakes), which is obviously not a major problem, but I have replaced the original tires (35mm I think,and a little knobbly) with smooth 28mm tires. Will my bike be suitable, comfortable and safe (for the bike and for the rider) on off-road tracks? Edit for more info:The disused railway is fully decommissioned, and is routinely used by walkers and cyclists (it is now a public bridleway). I haven't seen the surface personally but I gather it is fairly level and smooth but covered in a mixture of compacted soil, gravel and stone chippings and grass in some areas <Q> 28mm wide tires are perfectly suitable for riding hard-packed fine gravel trail surfaces. <S> You do have to be more careful when braking and cornering than on tarmac as the top surface is loose. <S> Larger rocks and potholes should be avoided of course. <S> As the size of the gravel particles gets larger or the depth of the loose gravel top surface gets deeper the less suitable 28mm tires will become. <S> I personally will ride 28mm tires on deeper, coarser gravel for short sections, but I would not want to do it for 50 miles. <S> As well as increased likelihood of punctures ad discomfort, narrow tires take more power to push through deeper gravel as then tend to sink in rather than floating over the top. <S> Update <S> [The surface] is fairly level and smooth but covered in a mixture of compacted soil, gravel and stone chippings and grass in some areas. <S> You'll be better off with your original 35mm tires. <S> With the larger tires you will not have to worry about what you will encounter, and you will be able to run lower pressure for better comfort. <A> Other than that, you should be OK. <S> Don't forget to have spare tube or two and pump in case of puncture. <A> Will my bike be suitable, comfortable and safe (for the bike and for the rider) on off-road tracks? <S> That depends on the rider. <S> I've watched people hop over 2-ft logs on road bikes. <S> That said, 28 mm tires and flat or drop bars on gravel or dirt roads is typically fine <S> as long you pay attention to your line. <S> However, I'm how vetted is your route? <S> If the unpaved section is simply an abandoned railway, most bikes might be in for a bit of trouble. <S> However, if it's a properly decommissioned railroad alignment that was regraded for non-motorized use, I wouldn't hesitate to ride it on 28 mm tires, but would likely appreciate the comfort of the wider rubber (provided it's a reasonably supple tire).
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Note that on flat hard-pack fine gravel you can decrease your tire pressure for better grip and comfort, but on deeper coarse gravel higher pressures are needed to avoid pinch-flats. I would switch back the tires to your old 35mm.
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3x9 speed to a 1x9 speed conversion I want to convert my 27 speed 3x9 to a 1x9. What do you recommend for chainring and cassette combinations? What are the cautions? <Q> With 1x conversions the usual question is how much high end you can accept losing to get the low end you need or want. <S> The cheap way is to figure out what ring to go with based on the above and then get a narrow-wide ring of the right BCD to achieve it. <S> Do all chainline measurements up front and use chainring spacers, a different BB spindle, and/or an offset chainring as applicable to achieve perfect chainline. <A> Otherwise, you can just buy a drivetrain set like 1x11 for $130+. <S> I did this trick a month ago on my mountain bike. <S> My option was 38t in front with a cassette 12-36.My experience was positive, but I recommend to use 32/34/36t in front, depending on your riding style and your power. <S> Fewer teeth if you ride out of roads. <S> If the price is a big question for you, check aliexpress for it. <S> I think this setup is good to ride 30-32 km/h on asphalt and for normal uphills, maybe even for not difficult mountains. <S> Advantages: fewer details, <S> less weight <S> ~400g I think, comfortable to use just one shifter instead of two. <S> Also, you will not get a big piece of dirt in your front derailleur as it happens often. <S> Disadvantages: After 100-120 km <S> I started to feel that 9 speeds can be not enough for long rides when you started to be tired and you will get more load on your knees. <S> Summary: <S> I like 1x9 <S> , it's very cheap (cassettes, chain), 9 speeds enough to ride on roads, out of roads and hills. <S> But will be not enough for long rides, 100+ km in my case. <S> But I will use it for winter rides, in my region, regular temp is -15C and my usual winter ride is 25-50km. <A> The tricky part is finding a 9spd derailluersetup that can shift to 40t. <S> I've used a 9 spd XT rear long cage with a Wolftooth roadlink derailluer cage extender to successfully shift a 9 spd 11-40 cluster. <S> This page is a good summary of <S> do it yourself options <S> Building wide range 9 speed cassettes <S> SunRace and some other manufacturers now also make 11-40 and similar wide range 9 speed cassettes.
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As I understand from your situation, you need a cheap option just to try. Much better to use narrow-wide chainring in the front, to keep the chain on the chainring. One thing to keep in mind is that you can use 40t 10 speed cogs to extend a traditional 9spd cassette to an 11-40. To figure out what cassette and ring size to get, the best approach is to use a gearing calculator to play with the options in comparison to what you need or would like based on your experience with bike's current gearing and how it's working for you where you ride.
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Can I use a Tubular tyre in a Clincher rim? Just tried it - my trekking clincher rim was too deep, so have to use 4 layers of tape to keep side out of rim, but then tubular started to travel forward even during slow acceleration. Would you try to use glue on all 4 layers + tubular, some special tape or change rim ? No surprise seller told me it is possible... <Q> Would you try to use glue on all 4 layers + tubular, some special tape or change rim ? <S> Change rim <S> The more layers of tape and glue you introduce the less firm the tire is attached and the more weight you add to your wheel. <S> You want your tire firmly affixed to your rim for turning, braking, acceleration (on a rear wheel) performance. <S> No surprise seller told me it is possible... <S> Sellers say lots of things are possible. <S> Possible does not mean "safe", "performs well", "is recommended", "is best" etc. <S> Sometimes sellers do not have your best interests at heart. <S> It is also possible to use and angle grinder to cut down the walls of the rim. <S> Then you would need less tape. <S> Please don't do that. <S> But, if you do we'd like video. <A> I'm linking two arbitrarily selected images of clincher rim and tubular rim profiles. <S> The first one is from m2endurance.com . <S> Your clincher rim has little hooks on the edge of the rim. <S> Those grip the beads on the side of your tire. <S> This image is from sdeals.com , and this is what a tubular rim looks like in profile. <S> Tubular rims have a curved gluing surface. <S> Tubular tires are round. <S> You glue the bottom side of the tires to that curved surface. <S> You mentioned tape, and maybe you were using tubular tapes. <S> Same principle, tubular tape will adhere to the curved surface. <S> I'm not sure what you did exactly. <S> If you put four layers of tubular tape on top of each other, then the tape is only glued to the base of the clincher rim, where a tube would normally sit. <S> I don't trust the bottom layer of tape to adhere sufficiently to the clincher rim's surface. <S> It is likely sticking to a smaller surface area than it would on a proper tubular rim. <S> I'm not that sure <S> how well tubular tape adheres to other tubular tape. <S> Whatever the case, everyone is expressing alarm because tubular tires, glues, and tapes are not designed to work with clincher rims. <S> There is no way to get sufficient adhesion. <S> If you ride that, you will crash. <S> The seller was completely irresponsible, or perhaps their English is really poor and they had no idea what you were asking. <S> These tires are mounted without glue . <S> I've heard that they don't ride very nicely . <A> I've just spend time learning about tubulars over the last several weeks. <S> The advantages of a tubular seem to be very slightly faster over a comparable clincher. <S> The downsides are a lot more preparation work, and that a flat is very bad because they take a lot of effort to fix. <S> So if you've got a team car right with you, which is carrying spare wheels <S> then that's great. <S> But for the great mass of cyclists, the minor advantages of tubulars are outweighed by the massive downsides. <S> A clincher and a tubular use fundamentally different interfaces with the rim and therefore are built differently. <S> You can see the tubular is a tube that wraps a permanent inner tube. <S> The clincher is a "bowl" that wraps 3/4 of an easily-swapped inner tube. <S> This is better explained in a picture: <S> Left is a normal clincher, middle is a normal tubular, and right is what I think you've done. <S> I suspect your tubular tyre has multiple layers of tubular tape trying to fill the void that is the clincher's wheel well or Valley. <S> You may have become confused between Rim tape and Tubular tape which are very different. <S> Additionally, Tubular glue is often spread in multiple layers with four on the rim and two more on the tubular. <S> Tubular tape is used in a single layer. <S> Further downsides to this idea: <S> Your tubular tyre is only making contact with the rim in two thin stripes. <S> Its going to wear through the cotton pretty quickly. <S> There is some "give" in each layer of adhesive tape, which will allow the tyre to move around the rim, eventually tearing where your valve stem meets the inner tube. <S> This give will also allow the tubular tyre to squirm off the clincher rim, probably when you least expect it and likely while leaning/cornering. <S> In short, use the right rim for the tyre you have.
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Edit:in the interest of completeness, there is one tire, Tufo's tubeless clincher , that's a tubular tire with bead blocks that fit into clincher rims' channels. If you don't glue them securely, they can roll off, and you will crash.
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UCI rules on allowed brakes? I'm considering buying a TriRig Omega X braking system front & rear for a bike I intend to use in UCI events. I can't find the right document on their respective website, so I'm asking here hoping someone could elucidate whether or not the TriRig brakes are legal? from https://www.tririg.com/store.php?c=omega <Q> this is Nick the owner of TriRig and the designer of the brake. <S> Short answer: <S> yes, Omega X has been allowed to race in all stripes of UCI events, up to and including multiple appearances in the Tour de France. <S> Of course, there is some level of unpredictability in how any given commissaire will rule on any given day at any given event. <S> We have heard a couple rogue reports of the commissaire requiring the Front Plate to be removed. <S> But in general, you should not have a problem. <S> Thanks! <A> I assume your concern is the cover which exists solely to make the brake body more aerodynamic and thus would appear to potentially fall foul of the "no non-structural fairings" rule. <S> Fortunately for you, brakes get an explicit exemption in the rules. <S> Per UCI's clarification guide : <S> The unit is considered to be integrated with the frame or fork. <S> The combination of the frame tube (or fork tube) + brake + cover must respect the minimum and maximum dimension rules and must be contained completely within the corresponding 8 cm box. <S> It then goes on to explain the 8 cm box, which basically means that the combined depth of the brake and the fork crown cannot be more than 8cm. <S> Now I'm not sure what the TriRig's exact depth is, nor do I know what fork you'd be pairing it with, but 8 cm is quite deep <S> and I'd be very surprised if you managed to exceed it. <S> For one final piece of evidence, note that TriRig claims their brakes have been run at le Tour de France. <S> Sure enough, it appears that, at the very least, they were run by Cofidis in the 2013 Tour TT stages. <S> If there is any race in the world where the bikes are scrutinized by the UCI, le Tour would be it, so if they've been run there, they should be fine for any race you might enter. <A> Assuming you're in the US, UCI rules on bicycles in general do not apply. <S> Actual UCI rules only apply "at events that select 17-18, U23 and Elite riders for international competition or national teams. <S> All bicycles used in National Championships (for UCI recognized classes listed above) and NRC races must comply with the current UCI regulations." <S> See 1. <S> General Regulations , 1I1, paragraph f (p. 27) : <S> (f) Bicycles must meet current UCI technical regulations at events that select 17-18, U23 and Elite riders for international competition or national teams. <S> At the discretion of USA Cycling, UCI rules may be adopted or modified for other National Championships. <S> I seem to remember a huge driver for this "loose interpretation" for a "legal bicycle" is to allow the use of triathlon-specific bicycles that don't meet UCI regulations in lower-level races. <S> No one wanted to prevent triathletes from participating in USA Cycling time trials with triathlon bikes that don't meet UCI regulations (3-1 aspect ratios, etc) or force them to buy another UCI-legal time trial bike. <S> Note, however, paragraph b (bolding per original): <S> (b) There may be no protective shield, fairing, or other device on any part of the bicycle, which has the effect of reducing air resistance except that spoke covers may be used. <S> In my experience with USA Cycling events, I've never seen a bicycle equipment check. <S> If what you're riding looks like a legal bike you should be fine, although it's impossible to rule out someone enforcing a strict interpretation of that rule. <S> I'd say USA Cycling's attitude seems to me to be, "If you're not good enough that someone else gives you a bike to race on, we don't really care if what you race on is exactly UCI legal or not."
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All bicycles used in National Championships (for UCI recognized classes listed above) and NRC races must comply with the current UCI regulations. The addition of a cover to a braking system ... is authorised. So generally, it appears it has been ruled legal.
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Minimum dimensions of bike storage shed I am interested in buying/building a storage shed that can hold three standard 19" mountain bikes. Ideally, the space would be as small as possible while still allowing one person to get the bike in and out. I am fine with having to take all the bikes out to get to the one I want, but I don't want to have to disassemble the bike (I don't even want to take the wheels off) to put it away. What dimension should the shed be and how big does the opening have to be? <Q> Width: If you hang the bikes on the wall, either "head to toe" or at staggered heights so that you can interleave the handlebars, then the width requirement is only slightly greater than 2x your handlebar width. <S> Call it 60". <S> Depth: If the wall opposite the hanging wall opens like a barn door, then you don't need to be able to fit your body in the shed, and it only needs to be as deep as the bikes are tall, so that's whatever <S> your seat height is above the ground, plus some clearance. <S> Maybe 36". <S> Height <S> : Length of bikes, end to end, plus some margin. <S> Maybe 60"? <S> Unless you're hanging them at staggered heights, in which case it's probably more like 75". <S> And you'll want a little bit of a pitch to the roof so it sheds rainwater, so a few inches higher at one side. <S> These are all inside dimensions. <S> If you're using 2x4s for framing, add 7" in each direction, plus the thickness of whatever your cladding is (plywood, chipboard, clapboard, etc). <S> And don't trust some rando on the Internet--measure this out carefully before you start cutting materials. <S> I don't know how tight a space you're trying to fit this shed into, but you might want to consider making it a little bigger than this. <S> Plywood comes in 4'x8' sheets, and every cut you save makes the project simpler. <S> Plus you can leave room for your N+1 bike. <S> Making a shed that they can roll straight into will be easier to use day-to-day, but the width will need to be the total width of all the bikes at their widest point, plus some margin, so that handlebars don't interfere with each other. <A> I have 1 of these, fits 2 bikes easily with plenty of space for a third, reversed. <S> Internal dimensions H: <S> 1170 <S> mm 3' 10 <S> " D: 1800 <S> mm 5 <S> ' 11" W: <S> 840mm 2' 9". <S> http://www.asgardsss.co.uk/twin-bike-locker <A> It should be at least as wide as the 3 bikes and as long as the longest bike and as tall as the tallest bike plus some additional space to put 2 bikes away if the one you need is the further-est (sp?) in the shed. <S> You need some extra space (couple of feet) all around to be able to move your bike in and out without struggling too much and <S> if there are racks in it, factor that in. <S> Other than that... <S> nothing much I can add.
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Don't forget to include/add individual bike locks for each of your bikes; a door lock on the shed is not enough.
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Should I bike or drive to work? (6.8 mi) I am moving next month and I need to figure out how to get to work. Option one is driving to work, which will take 15 to 20 minutes one-way. Option two is biking, which will take about 35 minutes according to Google Maps. The distance is 6.8 miles one-way, and the road is mostly flat. Assuming money/cost is not an issue, which option would you recommend? I really like the idea of biking to work, because I sit in my cubicle all day, and I want to incorporate some exercising to my commute (currently I walk 20 minutes to get to work.) My main concern is that I am not athletic enough to bike 6.8 miles one way. Is that a doable distance for beginners? Thanks!! <Q> I estimate 6.8mi as about 11km. <S> That is definitely doable for a novice, though it may not be as fast as Google's estimate at first. <S> Unless there aren't any traffic lights or stop signs, you should figure your overall average speed at no more than 15km/h initially, so budget 45-50min <S> your first time out. <S> (Google is notorious around here for not allowing enough time for stop lights in their time estimates, and that's without having to get back up to speed.) <S> Of course once you've been doing it for a month you'll definitely start bringing that time down. <S> If you're asking in this forum, you have to expect we're always going to recommend that you bike! :) <S> That said, there are places/roads that even I don't feel comfortable cycling regularly. <S> I can use them occasionally, but wouldn't want to ride them every morning and every night. <S> You'll want to check out the route <S> so you know you'll feel safe (or have a bail-out option) even if it's a busy rush hour, or you get caught in a sudden rain, etc. <S> I would recommend taking a weekend morning and doing a test-ride to work, stop and have a coffee, then ride home. <S> Take at least a half hour break, unless you're feeling really good. <S> You can get a decent estimate of how long the ride will take. <S> Plus it's the weekend, <S> so if you're slower on the return it's not a problem and it'll definitely give you confidence to do the ride on a regular workday. <S> Cycling to work is one of the best things about my current job; the exercise in the morning - especially on a sunny day - really helps me arrive at work in a good mood, energized and alert. <S> And the ride home literally helps burn off the stress of the day. <A> With a bicycle is doable. <S> Take into account time to change your clothes when arriving at work (as well as carrying them with you). <A> There is only one way to check it. <S> Try it. <S> As for factors, I am a bit overweight male of ~40, and not particularly athletic. <S> I have cycled to (another) workplace routinely some 10 years ago, but not as of late. <S> I did ride just about this distance (~6.8mi) to my to work last summer. <S> Urban commute, minor hills/slopes at some points, but mostly flat. <S> I was drenched in sweat, but not particularly tired. <S> It should definitely be doable for a beginner, if not in hurry. <S> It took me about an hour. <S> The only thing you might find out (as I did) is that for a day's ride for beginner <S> one way could be about it. <S> I didn't look forward to climbing on bike in the evening. <S> If you can have the logistics to cycle only one way when you feel like it, I think it'd be a splendid opportunity for you to keep fit and feel well. <S> My workplace is somewhat remote and a bike/taxi combo per day is a bit prohibitive. <A> I live in Lafayette, Colorado and commute 7.2 miles to Broomfield, Colorado six days a week. <S> I work for a company that takes phone calls so I am not active at all. <S> I do not have the car option, but that is a choice. <S> I started out of need and now I find myself taking my bike out on my days off just to ride. <S> The problem I ran into, I bought a cruiser from Walmart, when I ride in a pretty non-flat terrain. <S> I have improved physically, but the bike is getting harder and harder to ride because the terrain is so brutal for the cheap frame and hardware built into the bike. <S> The bottom line is, if I can, not only ride <S> but, enjoy riding 14.4 miles 6 days a week on a bike that is slowly falling apart, imagine how much you will love it on the right bike! <S> Keep riding and even though there will be days you get to work or home at the end of the day and collapse and say I am done, but you will find it is addictive as chocolate. <S> Congratulations on the new move. <A> Bike it. <S> It may suck at first if you're not used to it <S> but it will get easier until you get to the point where it's too easy. <S> Maintenance your bike more frequently <S> so your drivetrain lasts and always have the essentials on you to fix your bike in a pinch. <S> At the end of the day, this is not a very long or tough of a ride <S> so it's just about your will to do this.
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My advice to you is that if you really have a mostly flat commute and a bike for the type of road you will be travelling, ride that bike! With an e-bike is perfectly doable (and taking into account the battery life of about 2/300 charge cycles it is still cheaper than the car).
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Why is my new front wheel not spinning? Today my front wheel got flat. I took it for repair and when I went back home cycling it was very hard. It felt so heavy and that was not normal for speed 4, when I changed down to speed 3, 2, 1 it was also spinning slowly and feeling so heavy. I stopped the bike and spun both wheels, the front new wheel was spinning very slowly; almost not moving and the back older wheel was spinning fine and fast, so I realised there was a problem with the new wheel. I would like to know what the technician did wrong? How can it be fixed? I want to know because when I go back to the bike shop I wish to be aware of what has happened so he doesn't fool me. <Q> The most likely problem is that the brakes are rubbing. <S> If you pick up the front of the bike, hold your head near the brakes and spin the wheel you shouldn't hear any noise from the brakes. <S> If you do, then the brakes are rubbing and that's the first problem to be fixed. <S> To be honest, I'd guess that's 99% likely to be your problem. <S> If you have fenders, and the new tire is larger in size than the old one, then there may not be enough clearance for it; that can also be detected by listening for rubbing sounds. <S> (Note this is really unlikely if the shop only changed the tire.) <A> Additional things worth checking; Wheel is in the bike straight and secure Brake cables are seated properly Brake caliper is securely fitted and aligned well Brake pads aren't touching the rim, or the tyre <S> Wheel bearings are rolling freely Wheel rim width could be larger than the old wheel (if it was replaced) causing it to touch the brake pads set up for the old rim <A> Please remove the wheel from your bicycle (Quick release or bolts) and check for resistance moving the axle on it's own. <S> A common axle construction features cone nuts, and lock nuts both inside the arms of your fork. <S> I've often observed that if the lock nut is not snug against the cone nut, they relative tightness can change just removing the wheel for any purpose, such as the flat tire service that you described. <S> A properly tightened set of cone and lock nuts should move smoothly, yet have almost no play. <S> You don't want them so tight that your bearings are wearing down excessively, just to make room to move. <S> You don't want them loose enough to wobble or permit dirt and moisture into the bearing areas. <S> The lock nut is secured against the cone nut, once on each side of your hub. <S> Once you have verified your axle bearing is moving well, replace the wheel onto your fork. <S> It should be seated fully and centered (between the fork and the brake components). <S> This link provides a good how-to resource on adjusting the cone and lock nuts. <S> This page provides a decent photo pointing out the parts mentioned here . <S> Your front wheel will probably have no spacers. <S> Those are used on the rear axle. <S> I acknowledge prior contributors mentioned the bearings, but I felt a little more <S> should be said addressing them.
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If the brakes are fine and nothing else is rubbing, pop the wheel off the bike and try spinning the axle; if it doesn't spin freely then that means there's too much pressure on the bearings. Tyre isn't touching any fender or part of the frame
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Hard and noisy Shimano ST-EF29 front shifter with brake lever I bought brand new Shimano ST-EF29 (3x8 Speed) Shifter + Brake Lever (both left and right) for my MTB which I installed some 3 months ago. But it is very noisy (especially when shifting from 3rd to 2nd chainring on the left shifter). It changes super smooth and beautifully quiet from 1st to 2nd speed (chainring), a litle bit harder from 2nd to 3rd speed (chainring) but still satisfactory. The chain is not touching the front derailleur cage at 1x1 Speed and also not touching it at 3x8 speed). But the noise is quite loud and annoying when shifting backwards from 3rd to 2nd and then from 2nd to 1st speed (chainring). I noticed a small screw with the spring on the bottom side of the shifter and checked Shimano Tech website. It is called Reach Adjusting Screw and Spring (see photo). But it seems this screw is for brake lever adjustment so I didn't touch it at all. Is there a way to fix this? Is there a screw on the shifter/brake lever that needs to be adjusted? The cable tension seems right when changing from 1st to 2nd speed but when changing from 2nd speed to 3rd speed it is a bit hard. The thing is that when shifter is in 1st speed (smallest chainring) the cable is completely loose) so I am not sure if loosening a cable tension (at front derailleur) furthermore would cause shifting problems. The right shifter (Speeds 1x8) is working perfectly. I have no clue how to solve this. At first I thought it's because the shifter is new so it will become better/quieter with the time but it is 3 months already and the noise is the same. <Q> My initial suspicions would be either the indexing is slightly too far outboard, so that the cage is not quite moving far enough to push the chain positively down to the smaller rings; or friction on the shift cable within the housing is delaying or impeding the inboard movement of the cage on downshifts. <S> Try adjusting the indexing. <S> Front derailleur adjustment is a bit tricky <S> so I always follow Park Tool's front derailleur process . <S> Check the shift cable is running freely. <S> Detach the cable from the derailleur, pull on it to provide <S> so tension and work the shifter, the cable should pay out easily and smoothly on downshifts. <A> As Argenti surmised, it is likely an indexing issue with your front derailleur, and going through the process like you're just putting the front derailleur on the bike for the first time is the best way to discover and solve the problem as well as develop experience with a bicycle system. <S> Start at the beginning. <S> It's good that your rear system is working well and properly as this is a prerequisite to the indexing the front system. <S> Here are the shop instructions from Shimano for the front drive System that includes the ST-EF29. <S> Note the troubleshooting tips at the end of front derailleur install instructions. <S> Though one of these tips may solve the problem, these assume one is at the point of correct install and cable connection to the pinch bolt, so do start at the beginning. <S> A few things I like to offer up regarding the front shifting system are 1) position the front derailleur so that the derailleur's outside cage plate is parallel to the large chainring, and the closer to the teeth you can get (without interfering) <S> the crisper your shifting will be. <S> 2) pay special attention to the cable routing, especially very near and at the pinch bolt. <S> Many systems utilize a leverage tab the cable must be routed over for the proper force to be applied to affect movement of the derailleur. <S> Lastly, I'll point out that cable tension is altered with the turning of the in line barrel adjuster, located where the cable leaves the shifter body in the ST-EF29. <S> Counter- clockwise will tighten the cable and helping to move the chain to a larger chainring. <S> Clockwise movement of the barrel adjuster lessens cable tension, allowing a better cage-chain line up, quieting noise and easing shifts to small ring. <A> I would be checking the setting for the high limit screw in particular, while following a front derailleur set up process. <S> (make sure the rear derailleur is indexed correctly before working on a front derailleur) <S> The reason is that you report the shifting from 2 to 3 being a bit harder than the shift from 1 to 2. <S> I find that if the limit screw is just a smidge tight, it is this limit that you are pushing against to reach 3. <S> Then when you push the downshift to release the cable tension, the cable has to pull against the limit screw initially which creates a noisier clunk as the extra tension releases. <S> If the shifting is otherwise good, perhaps loosen the h screw just a fraction, 1/8 to 1/4 of a turn. <S> Remember what you do because if it doesn't help, you can always tighten it back again.
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A very small change in the way the cable is secured and therefore the line of force being applied to move the cage can mess up the shift.
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50/34 compact with 11-32 10-speed Shimano 105 - will 11-34 make climbing easier or change chainring As mentioned above...I'm running a 50/34 10 speed with 11-32 cassette but would like to change to a configuration that would make climbing hill easier. I live in a hilly area so every time I cycle, I can't avoid hills almost immediately, averaging 5-11%. So for a recovery cycle, I still can't avoid pushing high watts. I'd sacrifice top end speed and even tolerate gaps in the gear ratios elsewhere (which I know would make my cadence uneven here and there) to make the hills easier to climb. I enjoy high cadence so spinning going up a climb is my preference. I don't race so basically challenge myself at times and then need recovery rides. Is it an option to go for a 11-34 or 11-36 even with current config of 54/30 10-speed or maybe shoot for an 11-speed 11-32 or would retaining my 10-speed 11-32 and instead opt for changing the 54/30 compact to something else? My preference would be to make the changes on the cassette end if possible. I have a new 105 long mech so that should not need to be changed at least, so possibly only the cassette. Looking forward to hearing your thoughts/suggestions <Q> You are already pretty close to the limit of what can be achieved easily. <S> You could certainly stick a 34t cassette on there, but it's not going to make any appreciable difference over a 32t. <S> The next step is a 36t cassette, which is likely to need a MTB rear mech (9 speed XT mech works well with 10s road shifters). <S> Another thing you can consider is a subcompact 46/30 chainset. <S> Making both changes would give you a 30/36 gear ratio, which is extremely low for a road bike. <S> If you know your target power (z1 for a recovery ride) you can use the following websites to calculate the gear ratio you need. <S> http://bikecalculator.com/ <S> https://www.bikecalc.com/speed_at_cadence <A> The largest specified cassette sprocket size for the 10 speed <S> Shimano 105 5700 series derailleur is 28 teeth, for both SS and GS versions (see here ), so you are already pushing the limits of the derailleur. <S> The max cassette sprockets on new 11 speed Shimano derailleurs are only 30 or 32 (although the Ultegra RX800 will take a 34). <A> Wolftooth makes the roadlink that allows you to shift larger cassettes with standard road derailleurs. <S> You should easily be able to go to an 11-36 cluster with the roadlink and a 105 rear triple. <S> While the difference in gear inches/ratio isn't that big in absolute numbers, the relative changes do make a difference. <S> 34/32 = 1.06 <S> 34/34 = 1.00 <S> 34/36 <S> = 0.94 <S> While those numbers look very close, 34/34 is 6% fewer watts, 34/36 is roughly 12% fewer watts. <S> That can be the difference between redline and just cruising along. <S> However, if your budget allows, my preferred solution would be to switch to the newer 46/30 "gravel" cranksets with an 11/32 rear cluster. <S> Unless you are riding in a pack at lot at speeds above 40 kph, a 46/11 is plenty high enough for most riding. <S> The problem with 50/34 is that for me at least there is an awkward speed on rolling terrain where I'm fiddling between big/big and small/small. <S> Compact cranks work best IMHO when you can do most of your riding in the big ring and keep the small ring for climbing. <S> Since you are pushing the curvature limits of the derailleur with a 46t, it's important that you be able to get it within the standard 3mm limit. <S> Often frame mounts don't allow you to move the derailleur low enough.
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The problem with 46/30 is that your front derailleur might have problems shifting a 46/30 if you have a frame mount derailleur. A sub-compact 48-32 or 46-30 crank will get you low ratios but you will of course lose your high ratios. I've been riding a 46/30 11-32 for a couple years now on my road bike and for me it's a great replacement for the typical road triple setup. The difference between an 32 and a 34 or 36 with a 34 in front is significant.
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Can a Mamachari be fitted with an 11 speed 52-36T crankset and FD? I would like to upgrade this bike with a better and faster crankset, 52-36T, but I'm confused if my planned setup will be compatible with the bike I have. I have consulted in our local bike shop and they said that a Dura-Ace crank would fit but the FD will have a hard time or impossible fitting considering the top tube design of the bike. I'm not really sure if he saw my bottom bracket being really old. Might there be any modern bottom bracket to fit it at all? Edit: Finally found an enlightening link https://bike.bikegremlin.com/1297/bicycle-front-derailleur-compatibility/ <Q> Right now you have a threaded bottom bracket shell with a non-cartridge bottom bracket. <S> If the threads are ISO/English standard and the width is standard threaded BB road width (68mm) <S> then you can fit an external bearing road BB and road crank. <S> The BB shell looks a bit wide though. <S> The other major issue is clearance between the chainstay and large chainrings that the frame was not designed for <A> Alternative answer - if you want more climbing gears, consider a wide-ranging Internally Geared Hub in your wheel. <S> An 11 speed Shimano Alfine has 500% range, and a 14 speed Rohloff is also enormous. <S> This will return your bike to a vintage look, and do away with the entire derailleur system. <S> You'll also be able to keep that chainguard, whereas fitting a front mech will require you to remove it completely, or worse butcher big holes into the metal. <S> Downside - these hubs are not cheap, and could easily cost more than your bike. <S> Plus they need building into the middle of your rear wheel, and your bike frame needs some way to tension the chain, so longer dropouts, not modern vertical ones (though you can also use a chain tensioner in the same style as a rear deraileur) <A> After so many days searching the web, asking questions here and asking some local mechanics, I finally got an answer. <S> My bike can be fitted with modern Threaded Bottom Bracket and Dura-Ace Crankset. <S> Chainstay clearance is ok. <S> I will ditch the chain guard. <S> The only problem now is the compatibility of the Dura-Ace road FD with XTR 2x MTB shifter. <S> Base from this link <S> https://bike.bikegremlin.com/1297/bicycle-front-derailleur-compatibility/ , I'm willing to push this experiment for my ultimate sleeper bike. <S> If it fails, it fails but I will find a way.
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If you want to fit a modern crank you'll need to be able to fit a compatible bottom bracket. As for the FD, if I can't fit it because of the top tube, I will just weld an adapter to it for a braze-on option.
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Is this crack on my seat stay mechanically safe? Recently picked up a steel frame and realised there was a crack on one side of the rear triangle, right by the seatpost. Crack seem to be contained towards the outer part of the tube so does not seem to affect wielded joint. Since it's a steel frame, I feel like it's good to go but a buddy thinks otherwise. Anyone experience something similar? Is it safe or am I doomed for a tragic death ☠? Any help appreciated! <Q> I think the key question is: how much strength is the elliptical plate brazed over the top of the seat stay adding to the strength of the joint? <S> I'd guess it is adding some strength, as without it there is not much material between the main seat <S> stay tube and the brazed joint. <S> I'd be worried about a crack forming just below the joint which could lead to the stay detaching from the main triangle <S> However, if one stay detaches it likely won't be a catastrophic failure, because the other stay will still be supporting the rear triangle. <S> Really you need to consider the risk yourself. <S> If you are a heavy rider who rides the bike hard <S> there's more risk, obviously. <S> At the very least I'd periodically inspect that area to check for any other cracks forming. <A> My guess is that when the frame was made the solder didn't flow into that gap completely and it's been this way since it was new covered over by paint. <S> If it gets worse over time it can be repaired. <S> If you don't feel comfortable with it <S> you can get it repaired now. <S> Argenti is right, a worst case scenario is the seat stay detaching when you need it most. <S> Even if that happens you have other tubes to hold things together <S> so the rear wheel won't fly off - you'll have time to slow down and get off the bike, so you might have to walk a long ways. <A> The crack doesn't seem too bad, but imaging a situation when you descend on high speed and the road is turning, the bike is jolting because the road is a bit rough. <S> So, at this moment the seatstay detaches and it may feel like your tire suddenly went flat and you may feel a loss of stability.
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If you are an experienced rider you might be able to take such a situation under control quickly if not crash might be inevitable.
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Creaking on hard pedaling I'm trying to locate a creak when I pedal uphill. Tightened chainring bolts and rear derailer hanger. I don't see much to do with the bottom bracket (sram xx1). Pedals are tight. Chain, cassette, and rear hub are new. It sounds like it's coming from the bottom bracket but everything sounds like it's coming from there. What could it be? 2015 Mondraker Foxy carbon edit: It's not the bottom bracket or the chainring or the wheels. I can reproduce it by pushing the suspension. I have no idea what to do with the linkages though. <Q> I have a carbon hardtail which I used to ride the Great Divide MTB route last summer. <S> About halfway through I had a similar issue which I couldn't seem to resolve; a creak everytime I put power through the pedal stroke. <S> I took apart and cleaned the cranks, pedals, axle, checked BB bearings for play, etc... <S> No change. <S> Finally, I took my bike in to a local bike shop when we got to the next town and the owner there straight away <S> asked if I'd checked the rear axle. <S> I hadn't as it didn't seem a likely suspect... <S> When I put power through the pedals, the frame was flexing quite significantly ( exacerbated in part because of all the bikepacking gear strapped to it) and causing the axle to creak as it shifted on each stroke. <S> I gave it a good clean, added a drop of lube, tightened it up and... <S> hey presto, problem solved. <S> Not guaranteed to be this <S> but it's an easy thing to check (especially compared to pulling out your BB) so worth having a look. <A> Creaking from the bottom bracket is difficult to isolate. <S> It could be as simple as cleats not being tight, water in the bottom bracket, crank arms need retightening, or the most obvious the bottom bracket itself. <S> I am not familiar with your bike, but generally under load it is more than likely to be the bottom bracket.as <S> your bike is 5 years old <A> I had ,every now and then, the same creaking noise "from BB", then I happened to notice that my front wheels' spokes are loose. <S> I tightened them all by half a turn and the creaking noise seams to have stopped. <S> Check your spokes!
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It turns out, with the large amount of dust and occasional mud the bike had been subjected to and with no opportunity to give it a good thorough clean, some dirt had accumulated between the rear axle quick release clamp and the frame. I am leaning to the bottom bracket.
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Improve survivability of bicycle container The "white container box" lasted about 2 months until it cracked in multiple places. It was a cheap box(Dollar General variety). New container is made by Sterilite and much sturdier. I believe the old container cracked because of vibration and bumps transmitted from the ground to the box. Can someone help me with ideas on how to cushion the new box? <Q> The traditional solution on bicycles is metal wire basket. <S> Metal is tougher than plastic and mesh instead of <S> sheet metal makes it lightweight enough. <S> If you need something waterproof, put your things in waterproof bag or get a more expensive bike-specific rack box. <A> Wood is an often-overlooked material. <S> Its pliable and forgiving of vibration. <S> Plus its available in heaps of different profiles and weights. <S> You can construct the size of box you want to the millimetre, not requiring to make use of whatever you find. <S> For added durability, painting the wood allows you to express yourself, or a good location to attach reflectors and lights. <A> The second container looks better, but, IMO, will not last long either. <S> How is the container attached on your bike ? <S> You could place a piece of rubber between the container and whatever holds it. <A> I went with a much smaller box with a lower height. <S> I often scraped my leg hiking it over the old box on the screws holding the lid down. <S> It has 2 closures, but the added screws stops the rattling. <A> I've always had the best luck using a milk crate. <S> I attach them to the rack using hose clamps. <S> Hose clamps won't break.
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If I need something to be waterproof, I just put it in a plastic bag. The first container looks to be really thin and cheap, no wonder why it did not last.
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Got rust on chain and cassette I have a pretty new bike (5 years) and just recently got all the transmission very rusty ( https://imgur.com/a/AlCts9b ). Several things happened: · Degreased it thoroughly (probably too much) · Lubricated the chain and cassette with wax lube (brand: squirt). I've read that regular lube protects the chain from rust but I don't know about this one, couldn't find a thing. · Did a 7-day trip with the bike leaving it most days outside, so it got exposed to some humidity but I had no option of leaving it inside. if someone knows which one is the most probable culprit it would be helpful so I don't make the same mistake twice. Now that it's rusty though I'm unsure about what to do. I tried to clean the rust without dissassembling the whole drivetrain but it wasn't very effective. Should I dissassemble everything and try to get the rust out or just lube it instead of using wax and use it regularly? <Q> Note to readers - <S> Squirt is a wax based dry lube, the chain was not hot waxed. <S> The rust is cosmetic. <S> Its been caused because you stripped the protective coatings with the degreaser and did not cover the chain and cassette completely in a protective layer. <S> Did you dry the chain before applying the lube and did you drown the chain then wipe off excess? <S> Did you reapply lube over the 7 days? <S> A dry lube won't last that long. <S> For De greasers I use a citrus based cleaner or specific bike 'chain cleaner as these are not as harsh as many of the automotive ones. <S> They clean the chain without stripping it bare of protection. <S> Wet lube offers better protection in wet conditions. <S> You can get plated chains if the rust bothers you. <A> Quick links (or a joining pin) are not very expensive. <S> Coarse wire wool or a wire brush are quite effective at cleaning surface rust off. <S> When you re-lube, you may want to use more lube to get good coverage over all the links, then wipe excess off. <A> Looks like only a small amount of surface rust, so only a cosmetic problem. <S> I wouldn’t worry too much about it. <S> Dry lube is great for dry or dusty conditions. <S> For humid or wet conditions you should use regular or wet lube. <S> A new chain costs 10€ or so. <S> In my opinion it’s not worth the effort to spend time and cleaning products on it.
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Dry lube is great, in dry conditions and OK in damp conditions but you need to reapply it regularly and use the right amount (which is heaps, drown the chain then wipe dry). Cleaning rust off is definitely easier with the chain off the bike.
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Air transport of a MTB with hydraulic brakes I would like to transport my MTB on an airliner's cargo hold.What are the requirements concerning hydraulic brakes, do they need to be flushed? <Q> Tires on planes are a problem because they are pressurized above sea level atmospheric pressure. <S> The pressure on a commercial airliner drops below that at sea level, so the pressure difference increases which can exceed the pressure the tire can handle. <A> I flew with my MTB last year - no need to drain the hydraulics. <S> One thing you should do is get a couple of pad spacers to insert in the calipers whilst the wheels are out. <A> I've heard of airlines requesting that you deflate your tires, but I've never heard of people draining the hydraulic fluid from their brakes. <S> Two friends of mine recently flew from the US Pacific Northwest to US Southwest for a week-long mountain bike trip. <S> They flew with their bikes as checked luggage. <S> By their accounts, they did not need to deflate their tubeless tires (thankfully), their fork or shock, and they did not have to drain the fluid from their hydraulic brakes.
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Hydraulic brake fluid is not pressurized above sea level atmospheric pressure and the brake system is designed to withstand high internal pressure when the levers are squeezed anyway.
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My road bike seems slightly too big for me After riding for about 300km, I'm looking at adjusting some parts to fit me. First adjustment:Because I feel that I'm stretching a little too forward, causing my back to ache, I've decided I would decrease my stem from 110 to 90. Second adjustment:Because I feel that the saddle is too small for me, causing the sensitive area to compress, I've decided to change my seat to swork power (OEM). Right now I'm looking at my leg reach to the pedals. Currently I feel that I have to stretch a bit more than I feel comfortable to, while pedaling, so I'm considering if I should shorten my seat post or change my crank length from 172.5 to 165. HOWEVER my seat post is integrated to the frame, I feel like I shouldn't cut it (plus its risky as it is carbon). 165 cranks are rare: I only found Dura-Ace 7950 that would cost me $275, but it would be a upgrade from the current Ultegra.Also my friend is saying that changing my Ultegra BB to a Dura Ace BB would make my ride much smoother. Please advise me if all these changes I'm doing are advisable. Also crank change vs seat tube cutting!! Thank you for your reading time! <Q> Because I feel that I'm stretching a little too forward, causing my back to ache <S> , I've decided I would decrease my stem from 110 to 90. <S> You can help this by also moving your saddle forward . <S> If you combine that with raising your handlebars some by changing the stem angle, you'll shift your torso to be more upright, too. <S> That will also shift your weight back a bit, putting a bit less pressure on your hands and a bit more on your bottom. <S> Moving the saddle forward would also slightly shorten the reach to the pedals. <S> 165 cranks are rare <S> They sure don't seem to be. <S> A simple Google search returns many examples of Shimano 165 mm cranksets that would likely all be compatible with your bicycle. <S> Also my friend is saying that changing my Ultegra BB to a Dura Ace BB would make my ride much smoother. <S> Hogwash. <S> You wouldn't be able to tell. <S> You'd probably be surprised at how many amateur road racers use things like Sora or Tiagra cranksets, or won't bother paying more for Ultegra - much less DuraAce - over 105 or today's Tiagra. <S> ( Wheels are what gets the money - good aero wheels can save 40 or 50 watts - maybe more - at 30+ mph...) <S> Pros and higher-level amateurs ride high-end bikes because they get them for free <S> - it's marketing aimed at getting you to pay a premium for bling. <S> DuraAce doesn't make your bike faster. <S> All it really does is make your bike a little bit lighter and a lot more expensive. <S> How much better is a $275 DuraAce crankset than a $65 Sora crankset anyway? <S> IMO, don't worry about the grams until you get down to 2% body fat. <A> You can also experiment with raising the bars a little by flipping the stem over. <S> Dropping the saddle is reasonable if your legs are too extended. <S> The standard rule of thumb is your knee should be slightly bent at the bottom of the pedal stroke, with your feet level. <S> Changing to shorter cranks to effectively reduce the seat to pedal distance is inadvisable, I think. <S> The point of shorter (or longer) cranks is to match the cranks arm length to the riders leg length. <S> With shorter cranks you may find that you introduce other problems. <S> Depending on the design of your seat-mast, you probably can cut it even if it is carbon fiber composite. <S> Presumably you have a short seat post that fits into the longer mast. <S> If you are confident that the post will go lower into the mast and the clamping mechanism will not be affected <S> the mast can be shortened. <S> Cutting down a CFC tube does not affect it structurally, if you cut is correctly. <S> See this Park Tool video that shows how to trim a CFC handlebar. <S> A special CFC hacksaw blade is used with a cutting guide. <S> Before cutting the mast, have at least one knowledgeable person look at your saddle height, just to make sure you are not doing it needlessly. <S> About the Dura Ace BB, <S> yeah <S> , that's BS. <S> Does your friend have one he's trying to sell you? <A> Thank you all for your participation and advise. <S> I'm new to this forum so i might be using the wrong method to reply to your answers. <S> From the answers I've concluded that it is pointless to change BB <S> It is fine to change crank length but not an Orthodox method. <S> Shifting saddle forward aids in finding the comfort position too <S> Maybe get a professional to see if cutting seat tube (seat mast) is the right thing to do. <S> To answer some of your questions: <S> no, my friend is not trying to sell me his bb <S> maybe 165mm cranks are rare only in my area. <S> i bought the bike second hand cause i thought that would be the best way to learn Below is a picture of my integrated seat mast
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Reducing the reach with a shorter stem is reasonable if you think you are leant too far forward.
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Suspension compromise for urban use I ride an eBike in New York City. About 80% of the roads I ride are relatively smooth and 20% pretty bumpy. On my non suspension bike the 80% is great but the 20% is a bit painful. I understand the cons of suspension (expensive, brittle, slows you down, heavy) but having some way to smooth out those bumpy roads would be very nice (on a new bike). Are there certain types of suspension options that would minimize the cons while allowing you a break on the bumpy surfaces? The biggest con I would like to avoid is the slow down of speed on smooth surfaces! <Q> The slow-down of wide tires is not that big, but <S> they naturally even out high-frequency bumps. <S> The wider the tire, the smoother your ride gets on the rough roads. <S> Maybe, that's all you need. <A> Better suspension has a "lockout" which basically clamps them in one position, leaving you with a heavy rigid fork for the 80% of your ride. <S> Of those, some have a lever on top of the fork crown, and the fancier ones have a remote lockout as a lever on your bars (which means yet another cable going up). <S> Your second option is to change something else - either find better quality surfaces on other routes, or change the way you ride by going around the bumpy bits and not through/over. <S> You can also get off the saddle and use your legs as suspension for those short bumpy bits, which will also give you more control. <A> If you're looking to avoid replacing the front fork, it depends on where the discomfort is for you. <S> Here's a few things to look into: Discomfort at the seat: a seat with thicker / softer padding, or even a seat post with suspension. <S> Discomfort in hand and arm: <S> a better grip often makes a huge difference. <S> Also wider handlebars makes it easier to control, therefore less tiring on the arms. <S> If you're willing to spend the money to replace your front fork, some forks with suspension allow the spring to be locked, achieving pretty close feel to no suspension. <A> You might want to try a suspension seat post. <S> It might take the edge off on rougher roads. <S> If you only need a little bit of help, you might look a saddle with an elastomer insert. <S> It won't do a lot, but it might help enough if the roads aren't too rough.
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Apart from going the high-tech route of a front suspension with lock-out, you can also try to get wider tires.
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Project idea: Upgrade old MTB to road groupset for commuter? I'm thinking of building up a fat-tire commuter bike. I need fenders, racks and wide tires since I live in the northwest (potholes, rain, more rain, hills). I also need it to be fast since I want to be fast on my commute. I was thinking about buying an old MTB and replacing the groupset with something like the Shimano 105. There's plenty of nice old steel MTBs on Craigslist for ~$100. I would essentially only want the frame. The dropout spacing on the old MTBs is 130mm, just like the 105 hubs. I'd have new 26" wheels built around those hubs and use the 105 crankset, rear and front derailleurs. I'd also put in a drop bar and I think I should be able to use the 105 brifters with the MTB cantilever brakes. Then I'd finish it off with tires like gatorskins or marathons. Does that sound reasonable? Anything I forgot to think of? <Q> V brakes and mechanical MTB discs aren't compatible with normal road levers. <S> You'll need either V-brake specific drop bar levers or cantilever brakes. <S> Road cranks have narrower chainline and larger chainrings and MTB chainstays are wider. <S> You may run into compatibility issues here, too. <S> You probably won't be using the highest gears anyway, since Marathons or Gatorskins have huge rolling resistance compared to proper road tires <S> Fast, potholes and rack don't fit together. <S> Get a messenger bag or backpack instead. <S> The most difference is in ergonomics. <S> What I would do would be MTB groupset with road cassette, V-brake compatible levers and bar end shifters. <A> There are a couple of problems using a road group on an MTB frame. <S> (I checked: 105 5700 and R7000 cranks both work with 68 and 73mm shells. <S> Shimano specs are here , including a link to archive specs in PDF form.) <S> First problem is clearance between the chainstay and the chainrings. <S> Old MTBs were designed for triple cranks with a 40 tooth big ring and a 47.5mm chainline as opposed to a 50 tooth big ring and a 43.5mm chainline. <S> You might have a problem with clearance between a wide tire and the chain, due to the reduced 43.5mm chainline. <S> Also: <S> You'll want to look into what effective gear ratios you'll get. <S> Your gear-inch (or gear meter) values with 26" MTB rims will be lower than regular road bike with 700c rims . <S> You'll probably need quite a short stem as drop bars extend the hand position forward compared to flat bars. <A> You don't say what your budget is, but there are plenty of new drop-bar bikes that take fat or fat-ish tires these days, sold as gravel bikes or all-road bikes. <S> The bike I'm riding as my commuter will take 34-mm tires, for example. <S> One thing to consider if you buy an old MTB with 26" wheels is that (as I understand it) 26" wheels aren't that popular on MTBs this day, so your tire choices will get more and more limited as time passes. <S> Both mountain bikes and gravel bikes these days are using either 650B wheels (called 27.5" on MTBs, or ETRTO 584) or 700C wheels (called 29" on MTBs, or ETRTO 622).
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Drop bars and road components aren't going to make you that much faster. If you have a frame with 130mm rear spacing and a 68 or 73mm BB shell, you can fit a external BB, road crank and rim brake hub.
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Bicycle trailer that can secure cargo? How do you secure your prior purchases in your trailer when you go into another store to make more purchases? <Q> Unlike in a comment above, I'm not going to assume that you can carry the rest of your shopping when you go in the second shop. <S> But hopefully you can carry any valuable items, then leave cheap bulky stuff in the trailer. <S> I do this with panniers and backpack, buying the more stealable items first and keeping them with me, then buying fruit and veg, leaving them in an open pannier, then going to the supermarket for the rest of the food shopping. <S> The open pannier is on the basis that a closed pannier could be full of something more tempting than a bag of onions. <A> You could make your own cover from plywood and some hardware store parts. <S> But it’d still be pretty insecure. <S> Most things are just there to keep honest people honest. <S> Another option is to bike with your vicious looking dog (or child) in the trailer and leave him with the bike. <S> Not sure if that’s a good solution. <S> Related: <S> How do you lock up your bike trailer? <A> I can fit a handle and have a third wheel that goes on the front. <S> This would allow me to push my trailer around the shop/store like it was a pram. <S> However this is a very rare occurrence, I rarely buy enough to warrant this kind of transport. <S> Some stores may have a policy preventing the use of outside trolleys - supermarkets might restrict access to prams/strollers for loss-prevention reasons. <S> Something vaguely similar but not the same.
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Or get some plastic storage tubs that have a pass-through for a padlock and bolt those down in your storage unit. My bike trailer was a child carrier, and the boom can retract underneath.
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Tire blowout on long descent I was using mild braking on a very hot day, a couple miles down the hill the back tire blew out the sidewall on a Continental Ultra Sport 700x23C inflated to around 100psi. The rim was quite hot to the touch from braking. The tire is a few years old, but didn't show other obvious signs of coming apart or excessive wear. I'm going to order a replacement tire. Are there certain tire options that would be more resistant to this? Other than that, what else can I do to avoid having to get a ride home in a car from the middle of nowhere? Edit: added more pictures after taking tire off the rim with plastic tool: <Q> The ideal gas law PV=nRT can be used to work out the increase in pressure, as there's no room for the air to expand/escape. <S> Let's try some numbers. <S> If pumped to 100psi at 17 <S> °C (290K) then heated to match a metal rim hot to the touch at 57 <S> °C (330K) <S> the pressure would get to 114psi. <S> The tyre should be able to handle that even if rated to 100psi. <S> Even starting at 7°C and going to 77°C only gets you 125psi. <S> Altitude adds a tiny bit to this if you pumped up at sea level - around 5psi for a 3000m pass. <S> Here's a plot of pressure vs. temperature assuming you pumped your tyres up at 0°C and ignoring altitude. <S> The upper limit of the graph is approximately when your tyres and brake pads would be smoking; you couldn't get that hot because the pads would misbehave long before that. <S> Heat also softens the rubber, making it more likely to fail, but it sounds like you should have been within sensible limits. <S> I've blown out a sidewall like this because of a sticking pressure gauge. <S> A subsequent test suggested I'd put about 50% more in than I should have. <S> If you'd overpressurised the tyre a little, then the heating could have taken it over the edge. <S> Maybe it's going too far for you, but randoneuring I carry a spare tyre. <S> A boot is all very well sometimes, but I've seen a few tyres fail like this one and that won't go back together with a boot. <S> Long steady braking is sometimes unavoidable, but causes problems (including my own recent crash*). <S> If you can, it's better to let the speed get up a bit then brake just before each bend or when otherwise needed. <S> Spreading the heat between both brakes is also a good idea. <S> * <S> I was on disc brakes. <S> The resin holding the ceramic together in my rear pads melted, one of the front pads jammed in a wrong position and only engaged the rotor with one edge. <S> This may have been due to heat as well. <S> This all happened when I released the brakes to allow them to cool on a long steep straight descent. <A> Are there certain tire options that would be more resistant to this? <S> Your tire was appropriate to your task. <S> Any tire of similar quality would be no more or less likely to malfunction. <S> It's not perfectly clear from the picture <S> but this does not look like a tire blown off the rim from high pressure. <S> If a tire is over inflated - or heated to over inflation the tube usually blows out below the tire bead. <S> It's the tire casings job to contain pressure. <S> The flap with threads sticking out looks like tire casing that tore out from near the middle of the tire. <S> There is an excellent question here on Bicycle Stack Exchange concerning bike tire construction . <S> Either the tire was defective, dry rotted or weathered to the point where the stress of a high speed descent caused the tire casing to fail. <S> Other than that <S> , what else can I do to avoid having to get a ride home in a car from the middle of nowhere? <S> An auto mechanic friend of mine says "Anything mechanical can fail at any time". <S> Some things are more likely to fail than others. <S> Tires and tubes top the list for a bike. <S> As Chris H suggests, carrying a spare tire and tube along with some basic tools can help. <A> In general Continentals have served me well. <S> The Gatorskin models have tougher side walls, and the Hardshell version is even tougher. <S> I'm currently riding GP5000 tubeless and ride in very hot conditions (Including Egypt) with no issues. <S> I'm 100kg and like to descend fast (so maybe not as much braking), have never had a tire blow like this that was correctly installed and maintained. <S> The tire in your picture does appear to have cracks in the side wall, I suggest that the tire has not aged well if it is only a few years old. <S> This type of fatiguing can be accelerated by certain degreasers/cleaners, and prolonged exposure to sunlight (among other things).
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It does look like the tire casing failed near the middle of the tire next to the center tread. May I also suggest moving up to a 25mm tire (or even a 28mm if your frame and brakes allow) which may allow you to run slightly lower pressures, and offer benefits such as; fewer pinch flats, increased comfort, and lower rolling resistance.
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What's the lightest complete road bicycle that meets UCI requirements (except possibly being too light)? I've seen various claims over the years, but which manufacturer holds the record, today? Also, what size bike and which components go with the claim? Happy to hear about "custom" / "one-off" vs. (mass) production, but for one-offs it'd be great to know there's proof that the bike is race-proven or otherwise structurally sound. <Q> GCN did a piece a little while ago on a 4.28-kg bike . <S> The frame is a Cannondale, but everything has been customized to get the weight down, including stripping the paint from the frame and replacing all the bolts with carbon-fiber equivalents <S> (I hadn't even known there were carbon-fiber bolts!). <A> I only happen to know about disc brake bikes. <S> Groupset is SRAM RED eTap AXS. <S> Obviously, the bike doesn't meet UCI requirements in regards to weight. <S> Read more on <S> https://www.canyon.com/en-de/collections/evo-collection.html including a reference to a 3.7KG bike. <A> I would check the GCN video linked to in Adam Rice's answer. <S> I don't see a reason why that bike couldn't be UCI legal other than its very low weight. <S> When you push to 5 kilos and below, sacrifices in durability and practicality become increasingly inevitable. <S> Just to name a few: <S> You can shed 200 grams from the pair that most racers actually prefer to use. <S> You can lose 100 to 200 grams from the drivetrain if you don't care about durability or nice gear ratios. <S> The rear cassette can be all aluminium with gearing such as 11-21. <S> Chainrings can be carbon fiber. <S> Chain can be titanium. <S> The lightest carbon fiber road brakes are less than half of the weight of Dura-Ace, Red or Super Record, but no racer would ever accept them for a twisty mountain stage. <S> In general, carbon fiber anything can be built very light and still sort of safe, if you don't mind the excessive flex. <S> Who needs bar tape anyway? <S> I've seen people riding perfectly practical and durable bikes between 5 and 5.5 kilos. <S> Below that they seem to be all show pieces. <A> 2.7kg for a custom road bike with 2x10 gears and front and rear brake. <S> 4.9kg <S> (I’ve also seen 4.8kg) for a bike you can actually buy. <S> It’s surprising that the difference between custom and commercial bikes is that large. <S> You’d think that a large manufacturer has more possibilities than a single hobbyist.
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The Canyon Ultimate CF Evo Disc 10.0 LTD was recently announced as the lightest disc brake road bike, weighing 5.99KG. Tires can be very, very light, if you don't mind very narrow width, ridiculously low mileage and zero puncture protection.
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Use Brompton BWR 3-speed hub to create a full 700c wheel? I have been looking at getting an internal gear hub wheel for my commuter. I currently ride a fixie and I find myself wanting a lower gear at stop lights and a higher gear in straight aways. Basically I want two speeds: fast and something comfortable from a stand still while I get to fast. I would hate to end up adding a derailleur so I'm very interested in internal gears. I have ridden several bikes with Nexus hubs and I'm generally underwhelmed with the gear ratio. I was researching hubs and found the Brompton Wide Ratio Hub (3-speed) which has a gear ratio of ~246% (according to Wikipedia and JohnSAllen ) which is significantly higher than other 3-speed hubs. Normally the BWR on a Brompton bike would be paired with a 2-speed rear derailleur, which makes the ratio go to ~305%. But I don't care about that. I want the hub. I can find the BWR for sale online, but as far as I can tell nobody has put one on anything other than a Brompton 20-inch wheel. That seems like such a waste. So I'm wondering whether it would be insane/impossible to build up a full size 700c wheel with the BWR hub for use on my converted road bike commuter. <Q> A Brompton rear hub has a non-standard over-locknut distance of 111 mm, I think. <S> A single-speed bike probably has 120 mm. <S> So you'd need to cold-set the frame. <S> Sturmey-Archer (which I believe makes the Brompton hub) also makes a 5-speed hub that has about the range you want, although from what I can tell, the OLD on that is longer than your rear triangle's spacing. <S> So again, you'd need to cold-set the frame, although less violently. <S> Their other 3-speeds should fit 120-mm rear spacing. <A> It is possible and I wouldn't call it insane, but I would advise against doing so. <S> As Adam mentioned before, the hub is narrower than standard. <S> Washers might not work well due to the shifting mechanism, but I'm not sure about that. <S> The bigger problem would be the gearing - Brompton has tiny wheels, so the chainring is large with a low torque going through the fast-spinning hub. <S> A regular bike would need a smaller chainring, placing an unusually high load on the hub, which I'm not sure it would manage well. <S> Their 5-speed hubs are close to the same range and give much nicer gearing. <S> There is a reason the wide-range is only recommended for the 6-speed Bromptons. <A> You could use washers outside the hub locknuts to make up the narrower hub, as long as the axle is long enough. <S> You could just squeeze the dropouts (I've seen it done with tiedowns!) or a combination of squeeze and washers-- not ideal, though, for sure. <S> A bigger issue is: How does a Brompton hub address the hub torsion / control cable hanger issue? <S> You might need frame fittings. <S> Or coaster-brake-ish chainstay strap. <S> For an internally-geared hub I'd go with a Sturmey-archer or Shimano that is designed for a bike with horizontal dropouts <S> (I'm assuming that's what is on your track bike?) <S> instead of trying to make an oddball hub fit. <S> Another issue is that building the wheel around the hub would be spendy unless you DIY... but if you're asking this question you're probably not going to build your own wheel :) <S> Go to your LBS, tell them what you're trying to do, and have them order a 700c wheel with a Sturmey or Nexus. <S> You can change the cog on it, although that won't do anything for the STEPS between gears, which seem to bother you. <A> Don't mind input torque, it is the same no matter the wheel size. <S> Consider the huge gear jumps - 57% each. <S> Axle length is 148mm, if you have an aluminum frame, it might not be enough.
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While you'd be hard-pressed to find a different 3-speed hub with such range, I'd recommend Sturmey-Archer. Also, the wheel will be a little weaker to side impacts due to lower dish - not a problem for tiny Brompton wheels, but a 700C might suffer. If you just squeeze the dropouts in 4.5mm on each side, the frame might deform asymmetrically, the dropouts won't remain parallel and you'll be riding slightly sideways!
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Are modern clipless shoes and pedals that much better than toe clips and straps? I've recently returned to cycling after a couple of decades, and I'm trying to get familiar with the current gear and components. I still use toe clips and straps on the pedals on my 1990 Trek road bike. But clips and straps are so far out of fashion that you wouldn't even know that they used to be common. I can hardly find a mention of them anywhere. Why have the modern pedals and and shoes so completely replaced the old-style clips and straps? Are they really that big an improvement? <Q> Clipless pedals hold your feet more securely and release easier than toe-straps and clips. <S> As you are probably aware, it is possible to to tighten straps to the point where they must be released before the foot can be removed from the pedal. <S> A properly functioning clipless pedal will always release the riders foot. <A> They are easier to get into, easier to get out of, locate the foot more accurately and solidly on the pedal, and allow for better transfer of power all the way around the pedal stroke. <S> The position of the foot on the pedal can also be precisely adjusted, as can the range of float and retention force. <A> For me, a big benefit of cycling with "clipless" pedals is that when I "clip in" to my "clipless" pedals my foot is instantly firmly attached at my ideal pre-set position-- fore/aft, inboard/outboard, toe in/toe out. <S> When using "clips and straps" I am endlessly wiggling my foot to try to find the best position. <S> All this is adjustable by adjusting the position of the cleat on the shoe. <S> Also, purpose-built cycling shoes have a sole that is more rigid than other athletic shoes. <S> This supports the foot during cycling, which is not what your feet have evolved to do well. <S> Riding without proper footwear (beach cruiser and flip flops, in my case) can give you tendinitis surprisingly quickly! <S> I don't have the reputation to comment, or I would have just commented on one of the above excellent answers. <A> Apart from being safer from the clip and toe-strap pedals, the wide use of "clipless" pedals has come from marketing and fashion. <S> You need to buy clipless shoes to be used with clipless pedals; you will not be able to wear casual shoes for the clipless pedals. <S> The clip and strap assemblies are still available and these are to be fixed onto normal flat pedals. <S> I still use them myself. <A> Despite @ump's combative tone, he does back up what he's saying with links to evidence. <S> GCN has also done one or two episodes that mostly debunk the benefits of being locked into your pedals. <S> As far as I can tell, all the tests that attempt to prove or disprove the benefits of clipless pedals have been done on a treadmill in a lab; it may be that the benefits are amplified when riding in the real world. <S> I know that I (unscientifically) just prefer to be locked in. <S> But the question is not about flat pedals vs clipless, it's about toeclips vs clipless. <S> Between the two, I greatly prefer clipless pedals, for reasons already mentioned in this thread. <S> If you are riding with clips and straps, you either want a platform pedal that gives good support (these do exist), or you want a fairly rigid shoe so that you don't get hotspots from the pedal's plates digging into your feet. <S> And if you're wearing special shoes anyhow, it's not a stretch to go clipless. <S> In any case, clipless pedals weren't intended to replace street shoes with toeclips, but slotted cleats with toeclips . <S> Cleats have most of the disadvantages of clipless pedals, plus being much less comfortable (a tight toe strap can cut off circulation) and of course harder to get out of the pedal. <S> The advent of SPDs made it practical to have clipless pedals with shoes that are OK to walk in.
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The simple answer is that 'clipless' pedals and shoes just function better than toe straps.
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Mounting a 12v motorcycle light on bike seat rails? So now that I built a 12 volt (more like 11v) battery for my bike I would like to accessorize it with some 12v lights to get a unique look. I'm looking at motorcycle tail lights, but they all have two parallel bolts coming out the back 82mm apart. The rails on a bike seat seem to be about 50mm apart. Is there something I get at the hardware store to jerry-rig a solution? Back of the bike seat: (two horizontal rails 50mm apart with an angle at the end). Maybe I could zip tie in a ubolt pipe clamp somehow? <Q> I would just use a standard electrical mounting 4" crossbar : <S> You can run the wire through the hole in the middle, and the slots on either side should accommodate both the posts from the light and whatever you use to attach it to the rails. <S> (P clips, as Criggie suggested in a comment, would be the simplest approach for that.) <S> (You can buy them individually, but if you're like me you have a bin full of random electrical crap with a good dozen of them...) <A> Similar lights are often fitted to pannier racks, especially on e-bikes. <S> It wouldn't be hard to fabricate something. <S> The easiest way is probably to start with a saddle mount for a water bottle cage and make an aluminum plate. <S> Some sellers of offcut sheet metal on ebay will cut to size, then you'd only need to drill the holes, but you can cut it with a hacksaw. <S> I'd probably use 3mm plate. <S> I assume you've been sensible about light levels and colours and won't dazzle or confuse anyone. <A> I did this by bolting the light to the plastic part of my carrier rack which already had one hole for a reflector. <S> I just drilled two holes and pushed the mounting bolts through and added some spare washers to protect the plastic. <S> I zip tied the wires to the under of the carrier parcel rack and it works grat for me. <S> I have a 12V battery in the saddlebag and a small switch on the wire. <S> I do not use the brake lights just the running lights when riding at night and in fog.
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I've had a plastic part with the right holes that would be easy to modify, but it came with a topeak rack.
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Bikes and wiring trouble Do bicycles have ground wires and if so where are they I am trying to put a horn on mines and it’s kinda hard....it’s a bicycle any help would be very appreciated thanks. <Q> Just run two wires, a positive and a negative lead. <S> Both leads in the same casing will make for a more robust wire, less susceptible to vibration damage. <S> If you expect to run one of the leads in the metal of your frame, first make sure there is conductivity between the points you expect to run the wire. <S> Carbon fibre is not conductive. <S> Steel is great for this, and aluminium conducts but tends to have galvanic reactions at points it touches other metals. <S> Use a multimeter in Beep mode and then measure the resistance in Ohms between the two points. <S> Then compare that reading with the resistance of a length of wire that you'll be using for the positive run - I bet the frame will have a lower resistance, but when you cross things like the fork bearings it could add a lot, or it could be fine. <S> Only measurement will tell. <S> Do note that Paint is generally non-conductive <S> so you'll need to scratch through that to get a measurement. <S> To attach wires to a frame, the common method was a hose clamp with the bare wire under it. <S> This is ugly, catches and holds muck and water, and means you've got a bare area of steel underneath. <S> The last resort is to drill a small hole into the frame, and then tap it for a bolt and trap your cable that way. <S> Good side of this is you can do this in a convenient place. <S> Downside, drilling holes into a frame. <S> Personally I use an airhorn that is powered by a small canister that sits in a water bottle cage. <S> Works perfectly and is audible from inside most modern vehicles including trucks. <A> Bicycles don't have any wiring installed, which is why it's so important to add it yourself! <S> Doing this opens up a whole new world of 12V motorcycle accessories which will give your bike that custom look. <S> The frame is covered in paint which is non-conductive, so don't bother using that as a ground (I checked). <S> Instead just run two thin wires for the 12v lights in the front and two more for a horn switch. <S> The best way to do this is using black zip ties or velcro straps. <S> If your bike has internal cabling like mine does, there may be an additional hole available to run the cables, however doing so is difficult without special tools. <S> I wanted all of the wires self contained in a nice black sheath, so I'm using 24 AWG stranded twisted pair cable (commonly used for ethernet patch cables) to carry the current and then using a 15V Lithium battery to supply the voltage. <S> For my low wattage lights, it works fine, but be careful how much power you drive over the wires without upsizing. <S> Calculator here . <S> The horn requires about 4 amps or so for mine, but it's a momentary load meaning the wiring works well enough for brief usage. <S> At 4 amps, the 24 AWG wire acts like the perfectly sized resistor stepping down the 15V to 13V for the horn. <S> It's important to test the amperage (current) <S> yourself, as the listed amperage on the retailer sites seems to be a maximum demand, not the continuous draw. <S> You will need to calculate the amps, voltage draw and wiring necessary for your custom job of course. <A> That has been done for years on bikes some 20-30 years ago, and it was a PITA. <S> I remember modifying a dynamo attachment to be able to connect a "ground" wire to the dynamo, simply because the ground connection through the frame is botchy at best. <S> (The electrical current needs to flow through two clamps and the steering bearings, all of which yield variable conductivity. <S> The clamps may be irritated by vibrations, the bearings are hopefully well-lubricated, and grease is not the best electrical conductor. <S> The connections of a real cable are usually much more stable.) <S> Modern bike electric parts all use two-lead cables, and are usually insulated against the frame. <S> As the power from the dynamo is alternating current, and as dynamo and lights are insulated from the frame, the two leads are really equal. <S> It doesn't really matter which port of the dynamo you connect to which port of the lights. <S> As long as you do not somehow connect both ports of the dynamo to each other, creating a short circuit, or connect both ports of a light/appliance to the same port of the dynamo, you should be fine.
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You can also crimp a small ring or fork connector onto the end of your wire, and then trap it under a convenient bolt like a carrier/mudguard stay, or under the light or horn fitting itself. Don't try to use your bike's frame as ground. Don't use electrical tape, it turns into a sticky disaster.
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New bike is slipping gears Got a bike 3 weeks ago. It now slips gears WITHOUT shifting. only slipping when I pedal hard or uphill.. It shifts good. I weigh 250lbs. edit: with a new derailleur <Q> Even if a derailleur appears to shift well, it could be out of adjustment. <S> My shifter cable recently snapped and I replaced it. <S> I put on a new one, and after adjusting it to the point of the shifting being "good", there was still some skipping when pedaling up a steep hill; some finer adjusting took care of it (while also improving the shifting from "good" to "excellent"). <S> You mention that the derailleur is new, which suggests that the bicycle isn't. <S> A used bicycle can have a worn out drive-train. <S> If the chain slips on the cogs, a new derailleur won't fix it. <S> If the chain is slipping on the rear cassette, both the chain and cog need to be replaced. <S> If it skips on the front, then the chain and front rings will have to be replaced, and likely the rear cassette also (because the new chain will quite possibly skip on the new one). <S> A second-hand bicycle doesn't have to appear to be well-used to need drive train component replacements. <S> A bike that is used daily for year-round daily commuting can need a new cassette and chain <S> well before it's two years old, especially with lower-end components, even if kept clean and well-maintained. <A> When you pedal hard you are literally pulling the chain off of the sprocket teeth. <S> A new derailleur won't do anything to fix this. <S> Another possibility of ghost shifting - where the chain moves between sprockets on its own, but that feels different than the chain slipping. <S> Check the wear on the chain and cassette sprockets. <S> A $10 chain wear gauge is a good investment. <S> Sprocket wear can be assessed visually. <A> what about your gear or sprocket . <S> is there any clogs or it might been use for so long and have misalignment or become gear too sharp as when you pedaling it hard easily make the chain loose .. a picture of it will help to understand
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I'm guessing that this is a used bike as you specifically point out it has a new derailleur. The most likely cause is worn chain and sprockets.
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Liability Insurance - What if you break the law? Are there any insurance policies out there that cover you if you have an accident while say, jumping a red light or cycling the wrong way on a one-way road? <Q> Note that 'liability insurance' is for damage you do to others, and 'personal insurance' is for damage you sustain. <S> So your title suggests you want cover for, eg, running into a Rolls Royce when jumping a red light, while your question body suggests 'what happens to me if I go round the barriers and ride under a train?' <S> It's almost impossible to find insurance for illegal activities in general, and often even for non-causal/incidental minor infringements. <S> That makes sense if you start from the extreme cases "I want to insure my house before I set it on fire" or "I want to buy life insurance before I kill myself" and work backwards until you find a nice easily-defended place to draw the line... <S> "it's illegal so you're not insured". <S> Your normal cover on just about anything ( per Matt ) should give you some liability insurance and it may well pay out if your infringements are not considered relevant. <S> But if it goes to court you will almost certainly lose because the other side will be very keen to point out the law-breaking. <S> For personal cover it's harder. <S> There's are lots of UK articles about how to invalidate your car insurance by breaking trivial laws, like this one <S> but they are all very careful to say "might invalidate" or "may cause insurer to deny". <S> So if you, say, are on the wrong side of the road, hit a pot-hole and go over the handlebars you could well be covered because you would probably have been hurt even if you were obeying the law. <S> But if you hit that Roller above and wreck your bike you're unlikely to be covered for anything and Murphy's Law says the Roller will have a QC behind the wheel. <A> You would need to check the exact wording of your insurance policy. <S> It's fairly common for insurance policies to have exclusions such as this (from Wiggle's policy ): <S> any event which results from Your deliberate act or omission and which could reasonably have been expected by You having regards to the nature and circumstances of such act or omission; <S> Note that it's not the illegality of jumping a red light that triggers this exclusion, it's the fact that jumping a red light could reasonably be expected to cause a collision. <A> I live in New Zealand. <S> I believe the UK is very similar, but as always, you need to read the fine print of the insurance documentation. <S> If you do not have liability cover, specific cover for your bicycle(s) should include it. <S> Again read the policy document carefully, and if you do not understand it, ask the insurer. <S> If you belong to a club, especially if they are a member of a national body, and a riding as apart of an organized event, you are probably covered, but there are often exclusions (like if you prang into another member its not covered) <S> In many cases there are restrictions and exclusions - for instance its common to exclude any form of racing to time trials. <S> As far as the things you list, insurance is cover for unforeseeable accidental damage and loss. <S> Insurers are probably within there rights under the policy to decline such a claim as the loss in those situations is entirely foreseeable. <S> They tend to deal with such things on a case by case basis, and the outcome is not always to the claimants liking.
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As a rule home contents insurance has cover for public liability, so this cover would be available if you had an accident while riding your bike. So if you accidentally jump a red light then you would be covered, but if it's deliberate then probably you wouldn't be.
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Identification of non-standard frame feature and suitability of frame for mid-drive e-bike conversion My question comes in two related parts: firstly, what is the piece of folded, drilled metal projecting rearwards from the lower bracket in the photo above? Secondly, does this piece of metal have any significant implications for the suitability of this bicycle to have a mid-drive e-bike conversion kit installed? EDIT This is a wider view of the bike. In order to address matters brought up in current answers, I should point out that I am this machine's first and only owner and rider, and it has spent most of its existence gathering dust in storage. It is around ten years old, and I doubt that I have ridden it more than around ten kilometers. It was very cheap, less than $200 Australian brand new from Big W. I was considering installing a Bafang BBS or similar mid-drive kit. <Q> Can it be cut off? <S> Yes. <S> The frame looks like a high mount single pivot style rear suspension - with the shock mounting almost horizontally between the top front point of the swing arm frame and the downtube. <S> This might have chain length issues you would have to be mindful of - the chain 'length' changes depending on the rear axle's position along the arc of suspension travel. <S> A trickier conversion. <S> The bike doesn't look like it has been used a lot chainrings, wheels etc show few signs of wear - though it maybe an older style, older build. <S> a picture of the whole bike would help further. <A> Agreed that the folded metal bit is for mounting a kickstand, I do not believe this would would get in the way of mounting a motor. <S> There are two other potential issues I see though. <S> The down tube on your bike is very wide. <S> This won't keep you from mounting the motor altogether but it will force the motor to hang down a bit lower. <S> I'll try to demonstrate what I mean with some pictures. <S> You can see in the two following pictures that there is a bolt for the mounting bracket that, on a frame like the one in the photos (smaller diameter steel frame) sits beside the down tube. <S> This should not be a deal breaker, just something to be aware of. <S> Probably the bigger issue, where would you carry the battery? <S> There are not cage mounting points for a water bottle mount battery. <S> There is probably not enough room inside frame for a triangle mount battery. <S> You cannot mount a sturdy enough rack on this bike to carry a battery there. <S> That seems to only leave carrying the battery in a backpack, which I've heard some people do, but it would not be my preference. <S> You may be fine with this though. <S> So in my opinion, you COULD mount a Bafang motor to this frame, but there are other limitations that keep this from being a viable ebike conversion candidate. <S> I'd suggest you sell this one for what ever you can get for it & buy a cheap, preferabley steel framed, non-rear suspension bike for your conversion. <S> Good luck! <A> Given there's a hinge / pivot just forward of the front derailleur, I'd guess you have a MTB frame with rear suspension, and that someone has removed the rear shock and linkages? <S> I also see flat pedals with pins that are worn or abraded, so this bike has done a few miles. <S> The bottom bracket appears to be a traditional 68mm English cup and cone BB with a visible lockring, so this is not a high end MTB. <S> The welds also suggest a heavy steel lower-end MTB from the 2000's. <S> That flange has no bearing on a motor, and it should have the bottom mounting stud of the shock through the holes. <S> As for whether this frame would suit a mid drive motor, you'll have to read the requirements of the motor kit you're intending to buy/install. <S> I'd worry that the lack of chain stays in the frame would cause increased wear and strange handling. <S> The lack of a shock means your frame is also running on the end of all arcs of motion, and there's no absorption of vibration. <S> OPINION: <S> I would not motorise that frame in its current state. <S> EDIT: <S> answer was based on the first image only, showing the BB and immediate area.
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The only type of rack you could mount on this bike would be a seat post mounted rack, which would not be sufficient. A full photo of your bike might help confirm that, but as it stands that bike is probably really saggy in the middle, with a low BB and inclined to pedal scrape on the ground/road. On your frame, the bolt would have to be rotated down to below the tube, effectively lowering the motor. The piece you refer to is a kickstand mounting. As to whether it can be utilized in, or get in the way of, a conversion depends on the 'kit' use.
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Is my Trek FX2 really toast? I have a 2016 or 2017 Trek FX2 (if critical I'll look up exact year). Ride it daily for shopping, going to the gym and such. Store it outside, unprotected from rain. Took it to the store I bought it at to have new pedals and break pads installed. Guy at the shop noticed that the headset was loose. After opening it up (lots of rust inside) he's basically saying it's toast and he wouldn't recommend repairing it. Why? Because combined with the other things that need to be done, the total bill will come to about half the price of a new bike. Better to go with a new bike because this old one will just cause exponentially increasing maintenance and replacement costs going forward. I don't know the first thing about any of this and there is also a language barrier. I speak the local language where I live reasonably well but for technical discussions like this one it leaves a lot to be desired. (Thus it's also possible that I might have misunderstood parts of what he told me.) My question here is first whether this sounds plausible, or whether the guy is possibly trying to pull the wool over my eyes. And secondly if it does sound plausible, is there a better option than simply going for a new bike? How about replacing the frame and headset with a new one? <Q> The fact that you've left the bike out in the rain the whole time and that the chain is rusty suggest that you've not been looking after it. <S> It doesn't surprise me that it would now be damaged beyond economic repair. <S> I used to have a Trek 721, which I think is a predecessor model to the FX2. <S> Mine was kept under a roof and lasted longer than yours but, after several years of use, it too hit the point where enough stuff needed replacing that it wasn't worth doing so. <S> From the way it's been treated, it sounds plausible that your bike would now be at that point, too. <S> Assuming that they say essentially the same thing, you have two options: either pay half the cost of a new bike and have a bike that will work for maybe another six to 18 months, or pay the whole cost of a new bike and get a new bike. <A> Cheap wearing parts like brake pads, bottom bracket bearings, headset bearings, pedals, chains etc. <S> are basically all 10€ items which are easy to install. <S> You could do it yourself if you get the right tools. <S> The hardest part is buying the correct stuff. <S> We’d need more information about which parts are installed and what their current state is to give an estimation of the cost and effort. <S> Worst case in addition to the brake pads and pedals you also need a new chain, cassette, chainrings, cables, tires, handle bar grips, saddle etc. <S> Maybe some small parts as well. <S> This can easily amount to >120€ just for the replacement parts. <S> In the very worst case your hub bearings are worn (due to lack of maintenance) which would basically require new wheels. <A> Water is the enemy of bikes. <S> Trek fx series are not that difficult to work on, and I simply cannot afford to have lbs mechanics work on my bikes. <S> I am self taught, using the how to videos on YouTube as I have no mechanical skills. <S> If you do not have an area to work on a bike, best to buy a yum cha bike from a department store for the amount of riding you do. <S> When it breaks throw it away and get another one. <S> But make sure you keep the drive train well oiled. <S> You will get a few years out of it. <S> And it will earn lot cheaper. <A> I feel it's always better for the "greater good" to fix a bike, rather than dispose it. <S> However, maybe it's in good enough shape to be sold second hand. <S> I would ask the bike shop if they are willing to do a trade in. <S> Then it's likely they will repair your old bike (a headset replacement is a non-issue) and sell it to someone looking for a used bike. <S> Everyone wins: the bike shop sells a new bike, you don't have to feel like wool is being pulled over your eyes and someone else gets to enjoy your old bike. <A> The FX2 looks to be about a $US400 bike meaning repair costs could easily exceed its value. <S> You do not say where you live, but in much of the Western world the bike shop is possibly right, as the labor cost of maintaining the bike can easily double or triple the parts cost for a bike in this price bracket. <S> However, a bike that's 2 or 3 years old should not be in the condition that its uneconomical to repair. <S> How has it been stored and how much has it been ridden? <S> If so, then the bike shops advice is starting to sound more correct. <S> If you are prepared to do work yourself, and have some basic tools, the cost of maintaining a bike can be very small. <S> For instance a cleanup, grease of the headset is a simple 15 minute job (maybe 30 minutes first time). <S> A bike shop has a reputation to maintain and the cost of a new headset added to the labor makes more sense.
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It may be the bike now fits into the "Not worth fixing, but not worth not fixing" - i.e. as is, its unride-able so practically worthless, fix it and you have a ride-able bike, but fixing it will cost as much as it will be worth. If the pedals and brake pads need replacing, there is a good chance the chain and cassette are also significantly worn. I suggest that you take it to another bike shop for a second opinion and then decide how to proceed. If the bearing races are past there best, you can reassemble it and put up with a slightly rough headset that you can redo every few months.
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Build endurance on small hills I've got a bunch of small hills on the paved roads that follow along rivers by where I ride. They might be a few hundred meters (more or less), so it takes some effort to keep the same pace (or close). If I'm trying to build endurance, should I try to shift more or try to stay in the same gear a little longer? Is there a rule of thumb for how much you should shift in this case? I'm a novice rider with a decent road bike. <Q> To build endurance, ride farther. <S> Do repeats on hills. <S> Shift to maintain a more or less steady cadence as you climb. <A> I think in general there are two types of training rides: <S> For the first type you want to keep the same intensity through the whole ride. <S> I recently got a power meter and discovered that I tend to ride hills with much more power than flats. <S> I don’t know if it’s psychological or a side-effect of riding on the tops of the road bike handle bar, but 200W uphill feel like 150W on the flats. <S> So my suggestion would be to intentionally ride easy uphill but keep pressure on the pedals downhill and on the flats. <S> Interval training means short (~2 minute) but hard bursts of speed with breaks in-between. <S> The goal is to spend as much time (per training session) at your VO₂Max as possible. <S> VO₂Max is the maximum oxygen processing rate. <S> Or in other words: When you are breathing as hard as possible you are at your VO₂Max. <S> It’s easier to reach this level of intensity when going uphill. <S> Since it takes some seconds to start breathing hard, an interval should be at least a minute in length. <S> After more than two minutes or so your muscles will be exhausted and you won’t be able to keep up the intensity. <S> Spend the breaks with easy pedaling (e.g. riding back down). <S> They should be long enough (1 to 2 minutes) for you to fully recover. <A> If you want to increase your endurance, you need to build up your cardiovascular capacity. <S> So, ride the hill up as fast as you possibly can, as often as you can. <S> Shift <S> however you feel is comfortable, but you want maximum power out of your legs. <S> When you're done, you should be as completely spent as you can get. <S> Do that over and over again and eventually it'll be easy going at a normal tempo.
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Long and (relatively) easy rides to build endurance and hard but short interval training to improve VO₂Max and muscle strength.
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If I change my cassette, should I also change the chain? If I change my cassette to a new one, should I also change the chain? I measured the chain with a wear gauge and it's ok. Just to emphasize the obvious: I'm changing the cassette to one of exactly the same type. <Q> Depends on how worn the chain is. <S> If it's relatively new go ahead and use it. <A> As a rule of thumb, new cassette and new chain. <S> Keep the old one as a spare, but 250 miles is nothing and would be good to go with a new cassette. <S> Generally you should get 2 to 3 chains per cassette. <A> I think if it’s not worn much (you could measure with a sliding caliper) <S> you could keep using it. <S> Otherwise install a new chain and use the current chain when it’s time for a chain replacement. <S> Worn chain on new chainrings can cause chain suck, but I think this is not the case for cassettes.
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The consensus seems to be that a worn chain will accelerate cassette and chainring wear. If it's at or approaching 0.5% stretch, just get a new one.
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Relationship between speed and cadence? I am having a disagreement with a friend. It stems around the scenario of 2 identical bikes on the same gear ratio side by side. If the rate of pedaling is same for both do both bikes travel at the same speed? Or does the rider's weight play a factor? <Q> Speed is determined only by gearing, of which crank, cassette, wheel, and tire are components <S> Any 2 bikes using, say, 42t cranks with a rear 32t cog and 25c tires on 700c wheels at 90rpm will be going the same speed. <S> Bike type and size, rider/bike weight, and even front wheel/tire size and crank length don’t matter. <S> These other factors only effect how much power it will take to keep up that cadence with that gear combination. <A> The mechanical factors which translate pedaling rate to overall speed are: Gear ratio Size of wheels <S> The weight of the rider is not relevant for this question. <S> The weight of the rider would be relevant if you were asking about the power needed to keep the bike going, especially up any kind of hill. <A> There would likely be a small difference. <S> If you have, eg, a bike with a rear tire that has a 68cm diameter, the effective tire diameter is reduced by the amount it compresses when the bike is carrying a rider. <S> Let's say that the heavier rider is heaver by 80kg, and this causes the tire to compress an additional 1cm vs the diameter with the lighter rider. <S> The effective radius is 33cm vs 34cm, and the effective circumference is 207.34cm vs 213.63cm. <S> So he heavier rider would travel about 207.34/213.63 or 0.97 kilometer for each kilometer the lighter rider travels. <S> (In practice the difference would likely be somewhat less due to the dynamics of the tire. <S> The lateral stiffness of the tread would tend to make the heavier bike "scoot ahead" relative to the above numbers, perhaps halving the disadvantage. <S> This would depend on the specific tire/tread/pressure.) <A> The velocity is proportional to wheel's angular speed (same) and the radius, which must be measured in the point of contact. <S> If you want to quantify the difference, sit on the bike and masure the distance of the rear wheel axis to the ground for both riders. <S> Divide those numbers and you'll get the ratio how much faster/slower the other bike will ride.
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If the weight difference is significant and the mountain bike tyres are inflated to low pressure, yes the ligther biker can be slightly faster than the heavier one. The cadence (same) is directly bound via gear ratio (same) to the wheel's angular speed (rad per second).
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Is mountain bike good for long distances? I am currently living in a plane area. I use an MTB (mountain bike). My work place is 10 to 15 km away from my home. Temperature is around 36 degree in celsius in my region. Question : Is mountain bicycle good for this purpose? Edit: See the image of mtb below. One more thing roads are straight but there are few up and downs in my ways. <Q> 10-15 km is not a particularly long distance. <S> You can certainly ride and MTB on roads to commute to work. <S> You can make your MTB more efficient by fitting narrower tires with a road tread (or no tread) and inflating them to the higher end of their pressure range. <A> That depends on the type of mountain bike you have. <S> For example: XC bikes are sometimes referred to as the "road bikes of the mountain" for their long range touring ability. <S> If you wish to make your bike more comfortable for commuting, you can: Boost the handlebars with a stem raiser. <S> This will give you a more upright position more similar to a hybrid bike. <S> Swap out the tires with slicker less knobby ones for road use. <S> Lock out the fork <S> , so you don't lose energy to the suspension. <S> Add a rack and pannier bags, so you don't have to carry the weight of a backpack on your shoulders. <S> I boosted the handlebars on mine to make it more comfortable for on my back, and now I do about 10+ miles a day, everyday riding around town. <S> It's only marginally slower than the hybrid I was riding before. <A> 10 to 15 km is no problem on a bike. <S> If you are riding on roads it will be less efficient than a road bike, but it still should be no problem. <S> (it will depend more on your fitness level than the actual bike itself.) <S> My larger concern would be the temperature. <S> 35 degrees is very hot. <S> Perhaps you are more acclimatized to that than I would be, but working hard in that kind of heat could be quite strenuous on the body. <A> I guess I'll have to just say yes, it's good, but no, not the best option. <S> It starts with ergononomics; the build of the bike, and thus your posture, is way different from bikes more suitable for comfortably doing longer distances. <S> If you happen to want (to know about) the best option, look at what type of bikes Dutch people use for A to B purposes.
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Obviously an MTB will not be as efficient to ride as a bike designed for road use (such as a flat-bar commuter, road oriented hybrid or drop bar road bike). Increase the tire pressure, for less rolling resistance. Make sure you stay hydrated and cool if you decide to give it a go.
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Finding my physiologically relevant maximum heart rate I've always believed my maximum heart rate was 198 based on my performance. I'm 24 years old, so 220-24 = 196, but I routinely hit 197/198 during hard efforts in many rides, and never exceeded 198. When I hit 198 I can barely sustain my level of exertion and have to ease off in short order. Then one day I blew that number out the window when I sustained 202 for almost 20 seconds on a huge sprint effort. After the effort I had to get off the bike since I was dizzy and could hardly hold my head up and grasp the bars. So, for the purpose of defining my heart rate zones, is my "max" 202 or 198? <Q> The 220 - age (or any age based formula) is a myth that works well enough for roughly 60% of the population and puts the other 40% wrong. <S> That it persists to this day with such ready access to HR monitors and reasonably accurate sub-maximal tests to determine max HR astounds me. <S> (I blew over 210 when I was in my early 30's and now over 50 can sustain 170 for a hour and can probably reach 190.) <S> Training zones based on max heart rate percentages are based on average people and well enough for most of the population, but they are guesstimates. <S> You do not gain more accuracy from knowing max HR to a few beat per minute. <S> For defining your training zones, use 200 - its a nice round number. <A> Max HR isn't a particularly useful metric. <S> Not only is it particularly difficult to measure/estimate, but it can't be used to accurately define training zones, as there are large variations between individuals with regards to % of MHR they can sustain for various durations. <S> It can even change for an individual based on their current state of training. <S> Basing zones on Lactate Threshold Heart Rate (LTHR) is a much more useful metric for determining appropriate training zones. <S> The most common way to determine LTHR is by performing a 30 minute solo time trial as if it were a race, and taking the average HR for the last 20 minutes of the effort. <S> https://www.trainingpeaks.com/blog/joe-friel-s-quick-guide-to-setting-zones/ <A> Whatever maximum you have achieved on a bike is your maximum verified heart rate. <S> Since you have reached 202, it is at least 202. <S> Ignore the formulas since you already know better. <S> If you have an indoor trainer, or you have access to an exercise bike with a power meter, I would perform what is called a ramp test : <S> Start with very easy pedaling for ten minutes or so, to get warmed up. <S> Then, start increasing power by 30 watts every 2 minutes, and continue until you simply cannot turn the pedals any longer. <S> This test protocol is used when determiming lactate threshold and maximum oxygen intake in athletes. <S> Personally, at the end of ramp tests I have had my heart rate ticking steady at exactly 200 for the last couple of minutes -- It is the physiological maximum for me. <S> I have only reached 190 a few times outdoors, and at the end of long intervals (at threshold) it is commonly about 175.
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Presuming your HR monitor is accurate, your maximum is clearly at least 202. Your heart rate is guaranteed to sky rocket, and whatever you reach should be considered your maximum heart rate in cycling.
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How to stabilise the bicycle seatpost and saddle when it is all the way up? It is a standard column bicycle seat and I realised maybe I should have it raised to top (I can still stand the bicycle up using my toes) but the saddle rocks as there is no column to stop it moving and it doesn't have any other supports. I don't want it fixed forever but still want the saddle to be stable, with minimal movement. How can I do that? enter image description here The movement is 1 mm. I will correct this later. <Q> Your seat post is not all the way up, it's too far up. <S> If you need the saddle at that height you need a longer seat post. <S> As mentioned in comments there is usually a 'minumum insertion' point marked on the post. <S> Don't ride the bike with the seat post too far out of the seat tube. <S> It's dangerous as the seat post may collapse under you and <S> you risk damaging the top of the seat tube <S> even is that does not happen. <A> Extending the seat post past that point poses a risk of the seat post bending, or cracking the frame. <S> While 250-300mm seems to be the normal original size there are extra long seat posts available. <S> Lengths of 400mm are fairly common. <S> I did see a 700m telescoping (two sections) post for a folding bike. <S> You must also match the seatpost diameter to the bike's frame. <A> If you are lucky you can buy a longer post and replace your present one. <S> As mentioned in other answer, each post has a clear mark indicating the maximum usable length, and exceeding it is not a smart idea. <S> Visit a bike shop and search for a longer post fitting your frame. <S> If the diameter is not weird, you should fine one. <S> I mentioned the weird diameter out of personal experience: <S> on one of my previous bike the post had a larger diameter in the sub millimeter range than the new one I bought based on the millimeter size, and could not fit. <A> Have had the same issue..seatpost hight enough is too high..on the boundary from medium to large frame and have to opt for large and short stem instead to get a sturdy saddle height.. <S> As above mentioned not observing the minimum insertion <S> is incredibly dangerous and costly(will possible write the frame <S> off) <S> .. <S> if nothing else works go up a frame size..and shorten the stem a bit..works a treat for me(100mm instead of <S> 120mm stem for example).. <A> More info <S> The post diameter is often stamped into the post. <S> There are a number of diameters, some very close together, using a post slightly too small in diameter can result in a clamp that won't tighten enough allowing your post to gradually sink into the seat tube or turn easily. <S> Not a problem if you like to ride side saddle or with your knees in your face :) <S> A post that's just slightly too large in dia probably won't fit the seat tube. <S> If you've ever extracted a stuck post, it's obvious they're meant to fit tightly. <S> ebay has lots of long steel and aluminum posts; I bought a 400 mm long post from ebay a few years ago. <S> BTW, the longer the post, the farther back you sit and the easier <S> it is to lift the front wheel. <S> May not be noticeable, the seat can be moved forward on its rails some to compensate if it is. <S> Enjoy! <A> As other answers said, you should not ride w/o at least a few inches of seatpost inserted into the seat tube of the bicycle. <S> If you cannot locate a seatpost that is long enough (which you should be able to do), or otherwise want to use the seatpost you have, seatpost extenders exist that might be able to foot the bill. <S> Essentially, the are two parts -- a long tube that inserts into your seat tube (as a normal seat post would do) and an upper part that acts like another seat tube and into which you can slide your existing seat post. <A> I can only copy all the other answers. <S> Do not pull the seatpost too far up. <S> There is a minimum insert mark on the seastpost. <S> The reason is the post is not vertical so while sitting on it you are bending the post. <S> When the post is mounted too shallow, it can bend or break the frame. <S> You can bend or break the post itself, damage the frame or both. <S> Wery nasty injuries come from seat and seatpost failures! <S> If you need to pull the saddle up that much, the frame is too small for you. <S> you are and getting yourself bike that fits you.
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I cannot recommend using longer seatpost either, because longer post means higher bending momentum. Seat posts are usually marked with a line indicating a minimum insertion point. I would strongly recommend giving the bike to someone smaller tha
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How capable is my bike? I have recently purchased a new 'MTB' a few weeks ago, and have been enjoying riding ~12 miles daily on it on tarmac. I now wish to taste some off-roading on it. I wanted to know how much can my bike take given its specs, and what kind of terrain I should throw it on to the best from it. Here are the specs of it - <Q> If this bike is your only transportation and you have limited funds to fix <S> it don't take it off road. <S> Otherwise, don't worry about the bike. <S> You might as well break things on a less expensive bike first. <S> Make a plan to ease into off road riding. <S> Work your way to moderate riding - building skill and getting to know your bike. <S> Do moderate for several weeks. <S> Experiment a little with more difficult off road - ease your way into it. <S> Your goal should be to maximize experience and minimize risks. <S> Expect things to break. <S> You will get more flats. <S> If you hit rocks and holes you will bend wheels. <S> Don't get too far from civilization. <S> Several things will happen if you take the "ease into it" approach. <S> You will learn how to handle your bike <S> You will build strength <S> You will find out the limits of your bike and what qualities in a bike are needed to support the type of riding you like. <S> This information will be very valuable when you shop for your next bike. <S> The skills you develop will help your next bike last longer because you'll know what to and what not to do. <S> Carels suggestion of removing the kick-stand is very good. <A> The biggest weak points I can see are the front fork and the rear wheel. <S> This is a very basic fork. <S> It consists of springs that compress when loaded. <S> There are no adjustments. <S> It is basically a pogostick with a wheel attached. <S> The rear wheel has a freewheel hub. <S> The weak spot on a freehub wheel is the axle. <S> The drive side bearing is located inboard of the largest cog. <S> This leaves a long unsupported section of axle. <S> This the typical failure point. <S> It doesn't take much of an impact for the axle to bend. <A> It looks like a entry level big-box store bike. <S> I'd stick on pavement or easy gravel paths. <A> Check the documentation you got with the bike (if any) and the bike itself for a classification. <S> Often times you will find a sticker stating what terrain the bike should be used on. <S> The bike mostly consists of low level or no-name components. <S> It is certainly not intended for jumps and big drops. <S> However, if there aren't any hidden defects, it should absolutely be capable for forest roads or simple trails. <S> Even at lower price points hard tails can be very sturdy. <S> Expect some parts to fail. <S> Have a patch kit and a small pump ready and learn how to fix a flat tire. <S> Have a backup plan in case something breaks that you can't fix (the chain could snap, a wheel bent to a banana shape, the rear derailleur could hit the spokes and destroy itself and the wheel in the process, ...). <S> This backup plan can be "walk home for an hour" if that's OK, or a mobile phone (and reception) to get someone to pick you up. <S> The bike has a so called "Derailleur Gard". <S> This is a metal part that can protect your rear derailleur from light bumps like another bike being pushed into it or the bike slowly falling over. <S> If however this part gets hit at speed (which can easily happen when riding over rocks) it might bend the bike frame and destroy it for good. <S> Probably better to take it of. <S> The rear derailleur on your bike costs around 10$/€, prices in India might even be lower. <S> Cheaper to replace only a broken derailleur than buying a new frame.
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Start small for several weeks - easy off road riding at low to moderate speeds - and learn about how to choose your path and handle various terrain. It will fail quickly if subjected to log hopping or drops of more than a few inches. It is suitable for bumpy gravel roads at most. I would not do a lot of (or any) technical rides with it.
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2x front derailleur shifting adjustment for BB92 shell I have a bike with a BB92 Bottom Bracket and would like some input on adjusting the front derailleur to consistently move the chain between the small and big chain rings. Front derailleur is a top-pull, high mount, SRAM X9 for 2x10 speed that is cabled to SRAM XX Gripshift front shifter. Cable tension is as tight as I can manage for the wonky cable routing and limited space. Crankset is a Rotor REX 3.2 with ovalized rings (38/26T). Both crank arms were spaced according to Rotor installation instructions and would be physically unable to move any closer inboard due to chainstay clearance concerns. Chainline looks to be 60mm to the outer chain ring from the centerline of the BB shell. When attempting to shift from small ring to big; I can apply light force to the inside of the derailleur to complete the shift. If I don't apply light force; the derailleur will move the chain toward the big ring, but will then only drag across the ramping pins. It physically cannot move any further outboard enough to catch and pull the chain up onto the ring. <Q> I don't have enough 'reputation' to add a comment, but +1 on 'mikes' comment about the derailleur being too high. <S> If the derailleur is a bolt-on (hard to tell from pix), maybe the bike was designed for a larger big chainring? <A> When a front derailleur is adjusted correctly but still won't lift the chain to the outer ring I have had success using a little creative bending. <S> With pliers, small channel lock, or a small adjustable wrench bend the front tip of the derailleur just a little bit and test, bend a little more if needed (Top View) in the drawing below. <S> Or, bend the bottom inside edge up just a little bit and test, bend a little more if needed (Front View in the drawing below). <S> The goal is to bend the derailleur in such a way as to compliment the lifting motion when shifting. <S> Usually bending the front edge or the bottom front edge helps. <S> Looking at the pictures you will want to focus the bend on the part of the derailleur doing the lifting - looks like the middle inside. <S> I lean toward the "bend as little as possible" school of thought <S> but it's a judgement call on when to bend, where to bend, how much to bend, and if one should bend both the front and the bottom. <A> The derailleur is too high. <S> Also, you should not apply tension to the cable in the resting position beyond just keeping it tight, ie, don't force it tight through the clamp bolt, just pull it taught.
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Also, if the limit screws are all the all the way out, you might have to pre-load the derailleur travel a bit before tightening down the cable clamp.
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Type of permitted folding bikes on London trains & Tube? I have found quite a bit of information about taking folding bikes on trains and the Tube in London. Specifically it says you can take a folding bike pretty much anywhere. However, having examined the small print of various train companies in the UK there is usually a distinction drawn between Bromptons and the rest, i.e. Bromptons, which obviously fold up really small, are considered "true" folding bikes while the other types of folders appear to inhabit some regulatory grey area, halfway between a folder and a non-folder. I'm contemplating buying a Montague Crosstown . As you can see there, this has full-size wheels. Even if I wrap this in a bag I would anticipate getting some nasty looks if I take that on a busy-ish Tube / train in London, but I can cope with nasty looks. Does anyone know what the actual regulations are? <Q> Some UK rail companies, such as GWR (who operate some local trains in West London as well as mainline services) only consider bikes to be folding if the wheels are up to 20". <S> Folding bikes with a maximum 20-inch wheel can be carried as luggage without any restriction. <S> Please make sure you fold it before boarding. <S> That would exclude the bike you've pictured, unless you can pack it in a bag and call it luggage (checking the size of that too) <A> The authorative source would be Transport for London's website at https://tfl.gov.uk/modes/cycling/cycling-in-london/bikes-on-public-transport which states: <S> Tube: You can take a folded bike anywhere and anytime Dockland Light Rail: Can be used on all DLR trains, at any time London Overground: <S> Are accepted on London Overground trains at all times <S> TfL Rail: <S> Can be taken on TfL Rail trains at all times Trams: Trams only takes folded bicycles <S> Non folding bikes have time restrictions or are fully excluded. <S> Here's a bike-centric map for NON-folding bikes provided by TfL, dated May 2018. <S> http://content.tfl.gov.uk/bicycles-on-public-transport.pdf <S> As for your question of what defines a folding bike? <S> , that would be the mechanism of folding. <S> A bike whose main frame has any form of hinge would class as a folding bike. <S> You'd want to go out of your way to fold it as small as possible. <S> Remember a train is not a public place, and the "terms of conveyance" will permit them to exclude you. <S> So I'd suggest always turning the handlebars and lowering the saddle to make it look smaller. <S> I'd suggest not fitting bulky accessories too, a rack might be convenient but adds to the bulk. <S> Purchase of some folding pedals, or easily-removable ones like the MKS commuter pedals would be worth considering too. <S> Another interesting observation - <S> the image above shows the FRONT wheel is removed from the fork and laid beside the rear wheel. <S> I'd bet this bike is not a lot larger than a 20" folder when properly buttoned up. <S> How you stand/sit with the bike may need some consideration. <S> If you stand and have a backpack, then front-carry the bag on your chest with the bike on the floor below your bag. <S> This would save floor space. <A> Being a Londoner I would say this. <S> If you want to guarantee being able to take a folding bike on the tube go for a Brompton or something that folds to the same size. <S> Decathlon do very similar folding bikes. <S> You could probably get Montagne Crosstown on 80-90% of your journeys but there will inevitably be a day when a high on power tfl staff member stops you from getting on the train. <S> As @Dan <S> K said there are times when you can get away with taking a full size bike on the tube but that was on a Saturday. <S> I have done it before but there have also been times when I have tried to take a full size bike on the tube and been stopped. <S> I have also seen others within similar folding bikes to the one you want being stopped too. <S> To conclude to guarantee taking a folding bike on the tube get a Brompton or similar or as a previous answer says a folding bike with 20 inch tyres. <S> I hope this helps.
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Summary: Rules say you're allowed a folding bike, then you're allowed any wheel-size on a folding bike. You should absolutely consider a cover or water cape for the bike, to keep its dampness or oils from upsetting anyone.
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Road bike tyre impossible to get off I have a road bike tyre that is proving impossible to get off its a 700x25 on a set of tubeless ready rims (i know these can be more difficult to deal with). It was very tight to get on in the first place. I have tried a number things. I cannot free the bead to get a tyre lever under. I have tried using my thumbs (led to blistering), standing on the tyre and pulling the rim, as well as a set of pliers to pull on the tyre but it won't come loose. Any suggestions? I am considering cutting the tyre off if anyone as any experience of this that would also be useful. <Q> Road tubeless generally should have tighter tolerances <S> but there is no single standard <S> so the target measurement may differ between manufacturers leading to potentially problematic rim/tire combination. <S> Furthermore, tubeless systems that are designed to be run at high pressure (i.e., road) require beads that stretch very little, otherwise bead could become dislodged under pressure leading to a catastrophic deflation event. <S> The rigid bead can further exacerbate issues associated with tire/rim mismatches. <S> Once you have the bead in the center channel this should give you slack to get part of the bead over the rim. <S> When removing a tubeless tire go around the rim dislodging the bead into the channel. <S> You will often hear a load "thwack" as you dislodge the bead into the channel due to the release of tension caused by the tight high fit needed for an air tight seal. <S> This is the critical step that may require a reasonable amount of hand strength. <S> As you work around the wheel also check on areas you have already dislodged into the channel as the bead can work its way back out of the channel and back to the bead seat. <S> Once all of the beads on both sides of the tire are in the channel <S> you should have enough slack to get a tire lever under the bead and to dislodge the bead over the rim. <S> You may need a second lever, one to hold a dislodged bead in place, the second to continue dislodging more tire bead over the rim. <S> If the tire starts becomes incredibly tight while dislodging the bead, check that the remaining tire bead is properly nested in the channel and has not worked its way out of the channel. <S> Finally, if you are running tubeless tires on a non-tubeless rim, older varieties of rim (i.e., more than 5-10 years) may have no or an insufficiently deep center channel for the easy mounting/dismounting of tubeless tires. <S> In this case I would suggest forgoing the tubeless tire and sticking to regular clincher tires, most manufacturers still offer both construction types. <A> So I am actually answering my own question haha (created a proper login rather than just guest) <S> Managed to get the tyre of using the following A bed (yes a bed!!) <S> 4 tyre leavers <S> I lay the wheel flat on the floor and trapped one side of the tyre under the leg of the bed. <S> I then lent on the bed just above the leg to put some added weight on the bed to stop the tyre from slipping out. <S> I then pressed down using my foot with my own weight on the opposite side. <S> (This had to be done for both sides of the bead). <S> This unseated the bead enough to get the tyre leavers underneath (still needed four of them though). <A> This will be somewhat trickier with a road tyre, but the one time I had this problem (with a 27.5x2.8 mtb tyre), the way that finally solved it for me was to put the wheel on the ground and stand on the tyre on opposite sides. <S> Obviously this gives the less than ideal scenario of the hub/wheel bearing a lot of weight in a direction it wasn't designed for, so it's up to you if its a risk you feel happy taking.
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That said, most tubeless compatible rims will also have a deep center channel, which is intended to be used when mounting the tire and when removing the tire.
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What type of lubricant/grease is most suitable for brake and shift cables? I bought this lube some time back when I cleaned the bearings in my rear wheel: Now I am replacing all the cables on my bike and the instructions say to use white lithium grease. While I was at the bike shop yesterday, I asked the guy if the above ParkTool grease would suffice and he said it would. However, someone online said that this grease would not work as it would introduce friction within the cable housing. So what is the correct answer? If I already put that lube on my cables, should I clean it off (if that's even possible) and apply the proper grease? Edit : For anyone wondering, here's the cable kit I bought: https://www.amazon.com/gp/product/B00L8NDVD6 And here are the instructions: <Q> A heavy grease may introduce drag between the cable and housing, so a light lithium grease is preferable. <S> Using a teflon-coated cable will avoid the need for lubrication and prevent water from being in contact with the steel strands. <A> I use a dry-type chain lube. <S> Mainly because that is what I use on chains. <S> Any type of wet lube can cause dirt to stick to the cable and be drawn into the outer housing as the cable moves in and out. <S> Drip a few drops on your fingers and wipe the cable. <S> It leaves a thin film that doesn't transfer to your arms, legs or whatever you rub against where the exposed cable crosses the toptube. <A> Greasing cables does a couple things:- <S> It reduces friction, which can make shifting a smidge easier. <S> For this purpose, anything will work. <S> Grease will stick around longer, but oil can help too. <S> Simple paraffin (or bee's!) <S> wax will even work.- <S> It can help reduce corrosion. <S> If you ride in a wet place, water can get into the cable housing and corrode cables. <S> The corrosion can be straight up rust, but other types of corrosion are possible as well. <S> The corrosion can increase the friction between the cable and the housing (as well as weaken the cable). <S> Grease will help keep water off the cable and prevent this. <S> Best bet here is to use stainless cables, even though they're more expensive. <S> Barring that, a thin coat of grease will help make the cable last longer
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Lubricants can trap dirt and grit, meaning a greased cable would work better than a dry cable initially, but soon become contaminated such that the greased cable is worse.
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Alternatives to shorter cranks for knee pain I've recently developed pain at the front of my knees when cycling. I suspect this is caused by, or at least made worse by, my bike having cranks that are too long for my leg length (172.5mm cranks for 77cm inseam). Assuming crank length is a factor, a long term solution would obviously be to get shorter cranks. However, I can't afford that right now. Are there any bike fit adjustments that I could make to open the angle of/reduce the strain on my knees at the top of the pedal stroke? I've already experimented with various seat height and setback changes without much success. I'm prepared to temporarily compromise other aspects of my bike fit, if it would allow my knees to recover. <Q> Product options <S> You can purchase a bolt-on plate for either side that will give more pedal positions. <S> Any competent machine shop should be able to make you something like this, given the cranks to work from and test-fit. <S> Downside, this will increase your Q-factor by at least 10 mm, which could be uncomfortable. <S> Adds weight and surface area,and leaves end of crank arm poking well below your pedal. <S> On the positive side, it doesn't change your bike and can be removed in the future. <S> Can be fitted to hollow crank arms that can't be drilled. <S> Link: <S> https://tadpolerider2.wordpress.com/2015/05/11/short-cranksetscrankarms/ <S> Another similar option is a swing-arm pedal. <S> Its very similar to the plate above but includes a hinge/swivel. <S> Perhaps best-explained by an animation: From https://highpath.co.uk/pulse-swing-cranks/ Downsides, they add double the Q factor change of the plain bolt-on plate. <S> Significant cost, <S> and there's now another moving part in your transmisison. <A> If you are using clipless pedals and cleats one simple thing to try is moving the cleat as far back to the center of the foot as the adjustments allow. <S> This worked for me <S> and I got the idea from some articles on bike fit and cleat placement at cyclingnews.com. <S> This was from at least 10 years ago so those articles may be long gone. <S> This is a recent article from velonews that exposes a similar philosophy. <S> Personally, my experience has been that switching to 165mm or <S> 170mm cranks from 175mm makes a big difference in knee pain and comfort on the bike in general. <S> Knee pain can be just as much related to force through the joint as the range of motion. <S> Riding at a very easy pace with high cadence has been the most effective tool for recovering from meniscus damage as I get older. <A> Depending on your cranks, it may be possible to shorten them. <S> This is much easier than lengthening them. <S> This requires either a well-equipped workshop, or access to one. <S> The basic method will be mount your cranks to a junk/spare BB axle that can be held in a vise. <S> Position this in a pillar drill so that the drill axis is parallel to the BB axle. <S> Mark exactly the length you require. <S> Get someone else to measure your mark to confirm. <S> Drill pilot hole, with cutting fluid. <S> Test parallelity with BB. <S> Drill correct size hole, again with cutting fluid. <S> Tap using the correct 9/16" <S> left and right hand thread taps. <S> Deburr, refit, test ride. <S> (Optionally) you could trim off the old pedal mounting hole, and round off the end for weight and aero savings, but its also less to catch on the ground or on roots/grass. <S> You'll also need to use cranks of a construction with enough meat to still work after shortening. <S> Some cranks are hollow, and some are simply too slim to have enough metal left. <S> Ideally they should be flat on the outside, or have enough metal to grind flat. <S> Carbon fibre cranks are not suitable for shortening by this method. <S> Instead, buy some junk spares off your local ebay and use them for the experiment. <S> I see steel cranks may be unsuitable too, due to age and lack of metal once drilled. <S> Further links: https://highpath.co.uk/crank-shortening/ http://faqload.com/faqs/bicycle-components/drivetrain/crank-arm-shortening
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Upsides, you can shrink your pedal circle, and you can also lower your pedalling circle if that's what you need. Keeping your cadence high helps your knee health a lot. If you do go to 165mm cranks it's important to make sure you have appropriate gearing.
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How dangerous is a very out-of-true disc brake wheel? While walking to work this morning my eye was caught by an odd movement on a bike passing me several metres away. The front wheel was far from true laterally, though it didn't look out of round. It was on a basic hardtail/hybrid with front suspension with disc brakes; it was fairly close but not rubbing on the rather wide forks. If we assume that this wasn't due to impact causing weakening I couldn't see, how dangerous is it likely to be? <Q> Another danger of riding an out-of-true wheel is cornering. <S> When on the straight, the wheel may be "round" while wobbling from side to side. <S> But when leaning into a corner, the bike is no longer vertical, so that out-of-true in the rim is translating to an out-of-round as well. <S> So the wheel of the bike will be rising and falling ( "oscillating" ?) <S> sideways at roughly twice the wheel's RPM. <S> Effectively that could make the wheel loose traction much easier on the faster corners, or even at moderate speeds if the corner has any treacherous features like dampness, dust, sand, gravel, or even painted lines. <A> Quite dangerous. <S> The wheel can fail suddenly and without warning, causing an unavoidable and bad crash. <S> I assume the wheel had a broken spoke. <S> Wheels can usually survive a single broken spoke (unless you have a really low spoke count). <S> However, a second spoke is likely to follow and can cause the wheel to collapse entirely. <S> On a rear wheel this can still be somewhat manageable, but on the front wheel it’s catastrophic. <A> Riding an untrue wheel on a flat surface should be roughly equivalent to riding a perfectly true wheel on a correspondingly designed bumpy/uneven surface. <S> At least from the point of what forces are acting on the bike and the rider. <S> I.e., if there is a depression in a wheel, an equivalent terrain would be best represented by a BMX rhythm section with its periodical bumps: <S> It also applies for lateral untrueness: riding such a wheel should feel as rolling over periodic bumps from one side of the wheel. <S> It means the rider has to adjust to negotiate such "technical terrain" by redistributing own weight to maintain the balance and tire traction, even when riding a completely flat road. <S> As anyone who rode a rhythm section can tell you, not going with its "flow" will quickly throw you out of the balance and possibly off the bike. <S> Essentially, it is similar to riding with a turned handlebar: it is possible, but you have to constantly adjust your riding style, and your range of steering control becomes asymmetrical and thus limited. <S> Again, it is as if one is riding a mountain bike with straight wheels in a rock garden - the braking traction varies all the time as the wheels jump from stone to stone. <S> When wheels are in air, the friction is zero. <S> In the MTB case, having a well tuned suspension (both front and back) helps keeping wheels planted on the ground. <S> I assume the same applies for untrue wheels - having a suspension might hide some of the unevenness, but again it will spend a fraction of available suspension travel, making it less effective when you need it most, e.g. on big bumps.
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For an untrue wheel, for example braking will not be as effective and predictable because you essentially have periodically pulsing reaction force (both in direction and absolute value), and the friction force will pulse as well.
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How dangerous are my worn rims? I took my bike for a service recently and was told it needed so many repairs that it was more cost effective for me to replace it. One of the repair jobs was to replace the wheels due to worn rims. The shop told me they were so dangerous that they refused to replace the brake blocks - which were also dangerous - for fear of causing extra wear. I am happy to replace the bike but this is a bad time to do so. I'm looking to move house and my eventual location may impact what kind of bike I buy. I'd like to ride on my worn rims until then. The rims have a groove to indicate wear. The groove is still visible but it has become very shallow: I've sorted the brakes for now by tightening the cable. But realistically how safe am I riding on these rims and for how long? <Q> Rims are worn out when the groove disappears. <S> If the groove is clearly visible, well-defined and of uniform depth all the way around, the rim is not quite worn out and certainly not dangerous. <S> Given the repair shop's bad advice on the state of the rims and refusal to replace the blocks, I'd disregard all of their other advice about needed repairs. <S> I suspect they just saw a well-used bike and decided they could persuade you to purchase a new one. <S> Find a repair shop with a better reputation and get a second opinion. <S> Replacing and adjusting brake blocks yourself is relatively easy if you have basic tools. <S> Park Tool has an excellent web page and collection of videos <S> that walk you through the process. <A> You're definitely safe to ride these assuming the wear is uniform the whole way round and you're not just showing us the good bit! <S> Are you sure you didn't inadvertently give a secret code that you want to buy some carbon rims? <A> I had an experience with worn rims. <S> The wheel suddenly exploded, the tire separated from the rim, and I ended up cycling on the (metal) rim alone. <S> Since I was on a straight, even road, it was not too alarming. <S> As I remember it, I removed the tyre and continued to cycle home on the bare metal rim. <S> Consequences could had been worse, had it taken me by surprise in a more critical situation. <S> Braking power would have been poor, since the tyre was immediately shaved off. <S> This happened since I had rims that were very worn, and moments before I pumped the wheel to some considerable pressure. <S> I would replace the rim if the bike is used for riding downhill or at high speed. <S> If not, I would not be too concerned.
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New brake blocks will cause less wear as they will be free of hard particles of grit and metal that get embedded in the relatively soft rubber over time. My local shop will recommend things be replaced in front of your significant other if you want an upgrade.
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What should I upgrade first? I just got a new basic hardtail bike. I want to get better, and it’s not the best bike, so I want to upgrade it. I was thinking about changing the gear set up to 1 and 11 speed rather than 3 and 8 speed. I go out about mountain biking twice a week, and I really like it. My budget is £250. Any suggestions? <Q> Switching from 3x8 to 1x11 would be an expensive upgrade, well beyond your budget unless you get lucky hunting for used equipment, and may require a cascade of upgrades you hadn't planned on, which increase the cost further. <A> Disclaimer: I am not a fan of upgrading bike components. <S> I believe for most people, it's a waste of money, usually trying to make a silk purse from a sows ear. <S> Some succeed, but few do better than using the money to upgrade the entire bike. <S> (Replacing worn out components with better ones can be worth while if done carefully.) <S> With just two years riding and £250 to burn, here are the options I would consider, in order of impact on enjoyment and speed when riding. <S> Yourself: spend the money on coaching and joining a club where you get to ride with better riders than yourself. <S> Look into nutrition and decent cycling clothing if you have not already done so. <S> Maybe join a gym if your fitness levels are lower than ideal (but to be honest, riding is a much better way to get fit for riding). <S> A skilled rider on the crappiest bike will out perform an untrained rider on the best bike. <S> Dropper post: <S> Unless you are riding mostly non-technical XC, a dropper post, especially for a relative novice, is a big advantage. <S> Brakes: For anything more technical than bike paths <S> , decent brakes allow you to ride faster into corners with more confidence. <S> The more confident you are you can scrub speed in a hurry, the faster you will hit the apex, the faster you come out. <S> More fun and quicker times for less effort. <S> Stash the cash and start saving. <S> Ride the bike you have until you can afford an upgrade of the entire bike. <S> A 3x8 in decent quality dates back to mid 1990's. <S> If newer than about 10 years, 3x8 is probably a cheap, low quality Mountain bike. <S> 1x setups are a bit more than shiny bling, and here to stay, but they do not make a bike significantly faster or more fun to ride. <S> The advantages are more from removing the mechanicals from the stressed and crowded BB area of modern squishies, allowing frame designers more options. <S> If you must spend money on a 1x drive train upgrade, look at the Microshift Advent 9 speed. <S> Before spending money, watch a few of the "Cheap/Walmart MTB" videos on YouTube (e.g. the one below) and see what a cheap bike can do in the right hands. <A> I second (third?) <S> the suggestion that you not spend the money putting a 1x11 on a cheap bike. <S> I agree that it would be better to continue to ride the 3x8 drivetrain and wait for a new bike that is already 1x11 (or 1x12, or 1x15 or whatever the industry is into by then). <S> Short of buying a new bike/frame, here are my suggestions for cheap-ish upgrades, making a couple of assumptions as to what you already have: <S> New pedals. <S> Most lower-end bikes come with cheap plastic platform pedals. <S> I would recommend you get a set of clipless pedals and spd-compatible shoes. <S> You can find both fairly cheap these days, and they can be swapped over to a new bike whenever you finally upgrade. <S> You can handle the bike a lot better and generate a lot more power with clipless pedals. <S> If being attached to your pedals intimidates you (and it shouldn't), even an upgrade to a good quality flat pedal with metal pins will make a world of difference. <S> There really is no downside to tubeless once you have them set up. <S> Brakes - hydraulic disc brakes will give you a lot more confidence on the trails. <S> If that is not in the budget, I'd go for an Avid BB7 mechanical disk brake, which gets close to the same performance for half the price. <S> Dropper post, but only if trying to go very fast on the descents is a priority for you. <S> If you don't already have one, a good helmet jumps to the top of the list. <S> All your new parts aren't worth anything if you're brain-dead. <A> It really can transform the way a bike performs.
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You'd probably be better off saving up for a new bike--bike manufacturers are able to get parts at much lower cost, so when you buy a complete bike, you're getting the parts more cheaply than you could get them as an individual. The best upgrade you can do to a mountain bike is tubeless ready wheels and high quality tubeless ready tyres. Tubeless tires - Fewer flats, lighter, ability to run lower tire pressures.
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What can be done to seat post too long/saddle too high? Recently a mountain bike --someone's hand-me-down--, came in my way. Size wise it might be slightly big for my ideal but within the range of manageable, I accessed. After trying a few times, however, it became clear that its seat post becoming too long and saddle too high with the way it was. I broke the parts apart and the only way I could make do with this seemed not to use this post or any post at all, crazy it may sound, but it should work out only if the saddle cushion part immediately placed on the seating area. (Somehow the depth that the post can slide down is limited to half of the post length due to its structure: a "coil type' object obstructing and blocking the post. I'm a girl of 5 foot 2. Although the bike is a mountain type, I am not planning to use this for adventurous rides in mountains or slopes but for small scaled travel nearby with no bumps and/or environments as parks, etc. I am an experienced cyclist but also a city dweller, who would be cautious due to frequent casualties observed in the area where I am currently located: urban. <Q> I think what you are saying is that you need to drop the seat post all the way down into the frame, so the saddle is as close to the frame as possible. <S> You can't attach the saddle directly to the frame. <S> As long as the minumum length is inserted into the frame you will be structurally safe. <S> You can buy a shorter post of course. <S> However, if you need to drop the saddle all the way to the frame the bike is likely too large for you and possibly dangerous, as you will have no standover clearance. <A> Feel free to cut the seat post, but remember to keep a few inches in the frame. <A> You can shorten a seatpost with a pipe-cutter. <S> This assumes that the seatpost has a uniform cross-section over its length, and isn't thinned out or narrowed above the expected clamping area.
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You need a seat post to connect the saddle and frame. If the post cannot be slid all the way into the frame due to an obstruction it can be cut down to shorten it.
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Which tool for fixing wobbly crank? Any idea what kind of tool should I but to fix the loose left crank on my bike? I found this https://www.amazon.co.uk/Park-Tool-CCW-5-Crank-Wrench/dp/B0012Q5XAS but not sure if it's gonna suit. Or is it enough to buy only nut driver? <Q> The Park tool will work. <S> A 14mm socket and a ratchet will also work. <S> If the crankarm has been loose for some time there is a chance the movement has ruined the crankarm by distorting the square hole. <S> If there is no movement, ride for a few days then recheck the bolt tightness and for wiggle. <S> If everything is good recheck in a week. <S> then after 30 days. <S> If everything is still tight you should be all set. <S> It is a good idea to check the drive side while you are at it. <S> As the bike looks fairly new I would recheck all the hardware, stem and bar clamps, pedals, wheel QR etc. <A> If it is just the crank arm that's loose, then tightening the retaining nut at the base of the arm should be enough. <S> A regular socket (of the appropriate size, probably 14mm) is all you need for that. <S> You do want to make sure that it's just the crank arm and not the bottom bracket. <S> (Or the pedal itself.) <S> If you hold the other pedal and only the left crank moves, you're good, but if they both move the bottom bracket may need servicing. <S> It's a bit hard to tell from the photo, but it looks like your pedal may not have an 8mm hex driver, in which case you'll need a pedal wrench if it's loose. <A> You have a '3-piece crank'. <S> Each crank is attached to the axle on a square or splined tapered interface. <S> The central bolt pulls the crank onto the taper. <S> The bolt is just done up with a standard wrench or socket, but it really needs to be tightened to the proper torque which requires a torque wrench. <S> You can ask a local bike repair shop to do this for you. <S> As others have said when a cranks gets loose on the axle it can deform, will not grip the taper properly and repeatedly comes loose. <S> The only solution is a new crank arm.
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I would attempt to tighten the bolt then see if the arm still wiggles on the crank axle.
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Ultimate way to communicate while riding, an offline walkie talkie app? I find it super strange that there is no popular offline walkie talkie app for mobile devices. It could be really handy when you are biking with someone for a long distance! You could talk with your friends all the way without any problem. And the best part is that it is free because you will use local network Wifi, or bluetooth. I have been searching for quite some time and the only app I found was Intercom. It does exactly what I need, provides an easy way to communicate without an internet. But the problem is that it is super glitchy! It can just stop receiving and transferring voice. If you use headset which could be really cool when it is loud on the road, like it usually is, it just does not use headsets. And so on. Very bad... So the question remains! How to communicate with friends when you are on a ride? <Q> Have you tried talking with the people you ride with? <S> If traffic is too noisy to understand each other, look for different routes. <S> What is more, such busy traffic is not the time and place for chit-chat. <S> On a moderately quiet road I find it easy, and pleasant, to chat while riding side by side. <S> When riding in a file yelling and gestures work well. <S> If you go on a group ride it might be a good idea to agree on some useful phrases. <S> Select them in such a way that similar phrases sound distinctive. <S> There are a few hand signs you may want to learn. <S> Typically one uses the hand towards the centre of the road to indicate. <S> Most symbols are displayed low, just beside one's buttocks. <S> Stop: <S> Flat hand up with bent elbow (not in USA, might indicate turn)Hand down, palm facing rear. <S> Pot hole, obstacle:Finger points, down, at line that leads into the hole. <S> Slow: <S> Flat hand with palm facing down, wrist extended, elbow angled, hand and lower arm parallel to ground, move hand slowly up and down. <S> Here's a video explaining some symbols: <A> I'm not recommending the way we did this a few days ago, but I reckon it could provide the basis for something more sensible, not for chat but for some of the important stuff. <S> The club has a WhatsApp group and I have my phone on my bars. <S> Notifications pop up when there are messages. <S> When stopped at traffic lights I could read incoming messages (from someone who arrived late) and start to reply, but the lights changed, and texting while riding isn't easy or advisable. <S> How this could work better is to have a priority group that's the only one with notifications enabled, and stop to send messages. <S> Often when you really need to send a message you've stopped anyway, like a mechanical, or someone is lost. <S> Keep them short and to the point <S> and you don't have to stop to read <S> - it's no more distracting than checking your navigation. <S> That's worked for me when the group split on a windy hill <S> , the good climbers didn't realise, and the planned road was marked closed - did they take it or not? <S> (No, they went a slightly longer way round, realised they were missing someone, and stopped to find a message suggesting where to regroup). <S> Where this doesn't work so well is if you don't need to stop <S> : perhaps you get a vehicle stuck behind the group, and you'd like to let it past, either for reasons of courtesy or self preservation, so need to tell the leader. <A> when it is loud on the road, like it usually is <S> Then cycle on less busy roads. <S> It's more pleasant all round: it's quieter, there are fewer cars to worry about <S> , you're not holding up traffic, traffic isn't stopping you go where you want to go. <S> How to communicate with friends when you are on a ride? <S> Ride on roads that are quiet enough that you can ride side-by-side and just talk.
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If there are more than two of you, just talk to the person who happens to be at your side at the moment: even if you were just walking down the street as a group of, say, five people, you probably wouldn't be talking to the whole group, most of the time.
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My bike's adjustable stem keeps falling down My bike's adjustable stem keeps falling down. I tighten the nut as much as can but it seems no impact at all. Is it the wrong nut to tighten? <Q> What you have is an adjustable stem . <S> The headset is the pair of bearings in the head tube that the fork steerer tube runs in, that allows the handlebars and fork to turn. <S> You are tightening the correct bolt, however, check that the nut on the other side is captive and not turning when you tighten the bolt. <S> If it is not captive you need to hold the nut with another wrench as you tighten the bolt. <S> These types of adjustable stems usually have a a series of radial splines on the inner and outer parts that lock into each other when the bolt is done up. <S> The splines - being made of relatively soft aluminum alloy - get worn down and deformed, and can no longer hold the forward part of the stem in place. <S> If yours is repeatedly slipping the splines are probably very worn. <S> You can either find a replacement adjustable one, or knowing where you like the bars to be get a fixed one that replicates that position. <S> Replacing the stem is relatively easy and videos on how to do it are easily found . <S> The tricky bit is preloading the headset bearings. <S> You have to get this right or the bearings will be damaged when you ride, or in the worst case the bike will be dangerous to ride. <S> You also need to replace the steerer tube top cap. <S> This is necessary to set the bearing preload. <S> Even if you don't replace the stem the lack of top cap is allow water to enter the top of the steerer tube and accelerate corrosion. <A> There are quite a few adjustable stems where you would NOT tighten the correct bolt. <S> Also tightening this bold too hard can lead to a catastrophic failure of the stem. <S> For quite a few of those adjusting stems the tightening bolt is underneath. <A> I concur with the other answer m; I think if you were to disassemble this stem by taking the bolt out totally and have a look at the surfaces that get clamped together you'll see that instead of having ridge that align and grip each other like cog teeth, they have been worn smooth and can no longer grip each other effectively <S> If you're after a temporary repair you can use a small drill to drill one or two holes right the way through the stem, parallel with the bolt you're tightening, and then insert something (screw, bolt, chopped off bit of spoke etc that is the same diameter as the drill. <S> This will prevent the stem from moving but bear in mind that drilling it will also weaken it so if you're planning on using this bike for hardcore downhill or stunts at the local skate park, replace the stem with a fixed one (they're cheap). <S> If you're only commuting on it and maybe bumping up and down the occasional sidewalk it'll be fine. <S> it's loose and doesn't grip because it spent too long in a too-loose state, chewing itself to bits
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Analyse your riding style and see if you're riding with too much weight on the handlebars too, and if you replace this stem with another adjustable one, stay on top of the adjustment and keep the adjuster bolt tight; when it's loose it will cause a slipping which will wear out the teeth that stop it from rotating - in summary The solution is to buy a new stem.
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Combining Deore XT 9-speed shifters with Deore XT BR-M8000 (I-Spec-II) I wanted to convert my trekking bike to a mountain bike, and replace the Deore XT V-Brakes with disc brakes. However, the bike still has a perfectly functional Deore XT groupset (9-speed; unsure about the type). Googling the BR-M8000 set, I noticed it says it is 'I-Spec-II;, which seems to be some shifter and brake lever mount integration. Will I be able to combine these two or am I forced to replace my shifters too (and thus probably keep with the times and pick a 10-speed groupset?) Or is this just playing into Shimano's planned obsolescence hand? <Q> I-Spec-II is just some marketing hyperbole for shaping the brake levers and shifters so they fit together nicely . <S> It does not mean you have to have matching brake and shift levers. <S> You probably should be able to combine M8000 levers with older XT shifters, unless the XT shifters have a shape that does not work with the levers. <S> Comparing pictures of the brake levers with you existing ones should give you a good idea. <S> If Shimano brakes won't work there are lots of non-Shimano options from the likes of Tektro etc. <S> Beware that upgrading whole groupsets on older bikes can be problematic as frame geometry standards (bottom bracket width, chainline and rear hub spacing) have changed on modern bikes. <S> If you bike does not have proper disc brake attachment points <S> then really the solution is to go for a whole new bike. <A> I recently tried to mount an slx m7100 with my old shimano Devore shifter and they don’t fit together in the right place <S> I,e shifter levers are nowhere near brake lever so not compatible <S> I’m afraid! <A> If your shifter is a clamp-band shifter (mounts to handle bar via its own circular clamp), you can use any mechanical or hydraulic brake lever which will also clamp onto the bar independently of the clamp band shifter. <S> If your XT shifter is an i-spec mount (integrated with your current XT V-brake lever) <S> then you're dealing with the i-spec B system, which is NOT compatible with i-spec II. <S> However, there are some work-arounds and options available. <S> If you are satisfied with mechanical disc brakes which are activated by a cable system, your current v-brake lever will be appropriate and you don't have to change anything in your cockpit. <S> An m750, 60, 70 model brake lever is i-spec B type as are the same series of 9 speed shifters. <S> If your heart is set on hydraulic brakes, you'll need i-spec B compatible brake levers (the m8000 XT is I spec II and not compatible with i-spec B shifters). <S> Some hydraulic brake lever model numbers that are I spec B: <S> BL-675 B (Deore LX), BL-m820 (Saint), BL-S700 & 7000 series (Alfine), BL-785 B (XT). <S> There are more possibilities if the m8000 series lever needs to be used. <S> Read on. <S> Another option holds if you have the i-spec B shifters currently and want to run the m8000 levers. <S> This would entail buying the compatible top part of the shifter that includes a bar clamp. <S> Essentially you're replacing the i-spec part of the shifter with the clamp. <S> This will also come with the indicator window. <S> I do not believe there is an optional part that is the clamp without the indicator. <S> A clamp on shifter, again, allows the use of any brake lever. <S> The "ReMatch 1.1" will mate an I spec II brake lever to an I spec A or B shifter. <S> So you have some options. <S> Power to the people!
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Finally you can mate the incompatible i-spec B shifter to an i-spec II brake lever if you'd like to purchase problem solvers' integration piece . If you have a 9 speed XT drivetrain, your dealing with model numbers of shifters, derailleur's m750, m760 or some m770's, when they went to 10 speed with model m773 and above.
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Prescription glasses getting dusty and greasy I cycle to work each day, about 2.5 miles in each direction through a moderate sized town on paved roads (I don't use any dusty trails or go offroad etc). The climate is somewhat dry and arid with temperatures varying between 30c and -15c (I wear a scarf covering my nose when it is much below 0.) This issue does tend to get worse when it's very cold, but that could be due to it being more dry then also. I am in Colorado, USA if it helps, not right in the mountains but still at substantial altitude, thus the arid climate. However when I get to work each day my glasses invariably seem to be covered in both road dust, which I know how to deal with, but also a greasy film like layer which I do not notice until I try and clean off the dust then ends up smeared everywhere and requires several through cleanings with soap, cleaning solution and cloths and is nearly impossible to fully remove, giving a cloudy smeared look to the lenses. This is less of a problem on my way home as I can soak the glasses in appropriate solvents which eventually seems to clear them fully, but at work it really makes my day difficult. I would really appreciate any advice on either different prescription glasses I could use to avoid this issue, or some way to avoid this stuff depositing on them in the first place, or even something to wear over them. Though if possible I would prefer avoid anything that would look enormously out of place doing road biking in a city (if it makes a difference, I am female and in my late 20s). Given I mostly road bike I am not an expert on the various equipment used for this kind of thing. Eventually I might just get laser surgery to bypass the issue entirely but this is not an option for the next 6 months at least as I am recovering from another medical procedure. <Q> An ex-coworker of mine got a pair of goggles that he could put over his prescription glasses. <S> In his case not so much because of dirt on the lenses, but because wind bothered his eyes. <S> A lot of the ones you'll find are the high-durability ones for mountain bikers (with thick heavy frames), but it is possible to find lightweight (and not so ugly ones) like these: <S> (Note that this is not a product recommendation; I don't recall the make of what he actually has, this is simply the closest in appearance that I can find in reasonable time.) <A> There are cycling helmets with integrated detachable visor. <S> The visor covers the eyes. <S> Yet the helmet is open below. <S> I see them frequently on my commutes on rainy days. <S> Most are urban style helmets. <S> Ventilation might be a little lacking for very high temps and high exertion. <S> Here are two arbitrarily chosen examples: <A> The other answers assume your lenses are contaminated by external sources. <S> A different alternative is that you're the source of the greasiness, from sweat or perhaps hair products or similar. <S> Greasiness implies a biological source to me. <S> Check your helmet's foam padding, and if its manky then remove it carefully and wash it. <S> You can also try a headband or even a cap/casket under your helmet to "capture" sweat before it gets too near your lenses. <A> I can't think of a way to keep your glasses from getting dirty. <S> It sounds like the dirt could be carried by the air. <S> If you get laser surgery <S> so you don't need glasses then <S> all the stuff you clean off your glasses will go straight into your eyes. <S> You need something to protect your eyes and is easy to clean. <S> The shield would get dirty and keep your glasses clean. <S> You might be able to get away with only cleaning at home. <S> - Safety glasses that fit over your glasses - would look out of place <S> - Clip on sunglasses. <S> There are many different kinds of clip on glasses in different tint levels and they are not too expensive. <S> Or, you could have two, one for riding to work and the other for riding home. <S> I use a style of clip on sunglasses while driving that don't get a second look. <S> There are some interesting choices if goggles are an option. <S> They make mountain bike goggles that have tear-offs - disposable plastic covers. <S> When one gets dirty they tear it off and are able to see again. <S> I don't know of any goggles that fit over glasses <S> and they might look a little silly while on a road bike. <S> It would be nice if they made tear-offs for regular glasses. <S> I couldn't find any
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As you ride the air hits your glasses and gets them messy. Like the face shield you might be able to get away with only cleaning at home. Here are some options: - A helmet with a face shield.
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Is it safe to run disc brakes up front on a mountain bike that lacks a disc caliper mounting point in the rear? Upon sharing my thoughts in an answer to a Bicycle Stack Exchange question , I wondered about my suggestion to use a disc brake up front on a frame that, lacking a disc brake caliper mounting point at the rear and thus implying a lack of additional design considerations for disc brake usage in either the front or rear. I've a lifetime bicycle tinkering experience, and I know I've heard of running a front disc brake though I can't remember actually seeing this setup. So, given a bicycle, designed and marketed as a "mountain bike" but lacking a disc brake mounting point on the frame and also equipped with an after market, yet otherwise compatible, suspension fork which has both disc and rim brake mounts: would it be safe to run a disc brake (and rim, of course) in the front of this bike? If not, why? Any considerations as to safety or viability between the two types of disc systems, hydraulic or cable-mechanical? (Above and beyond the lever, including the ability to use matching front and rear levers in a mechanical disc + v-brake set up). <Q> A few years ago this was a reasonably common setup as sold. <S> I've certainly ridden an e-bike set up that way, with v-brakes at the back and a mechanical disc brake at the front. <S> I suspect this wasn't so much about stopping power as not needing maintenance between services, though in practice some adjustment was required even if less than at the back. <A> I ran this setup for a while on a Kona Stuff. <S> In fact, it came like that from the Factory as I had the fork upgrade option to Fox32 with hydraulic disc, but the rear was still V-Brake. <S> It was fine. <A> Mechanically i cant see any issues with this, however... <S> so if you find yourself pulling both lever just as hard you may find yourself going over the bars. <S> You may be able to mitigate this will a longer lever for the rim brake and a shorter lever on the Disk/hydraulic brake.
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Disk brakes, especially hydraulic, require significantly less force on the lever compared to rim brakes
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Why is a derailleur guard present only on more affordable bicycles? Looking at http://decathlon.co.uk , I see a derailleur guard only on more affordable bicycles, e.g. this one . This one does not have it, and there seems to be no obvious way to install one. Are derailleur guards important? Why does the more expensive bicycle (with higher component replacement costs if something breaks) not have one? Is it correct that one cannot be installed on the one shown in the picture? If it can be installed, is it recommended? One might always fall, or a parked bicycle may get knocked over. <Q> Derailleur guards are rarely found on more expensive bikes for several reasons: <S> Protection: These guards only protect from minor contacts. <S> Forces that would bend a typical derailleur would also bend these guards. <S> Weight: if the bike is handled properly (as owners of more expensive bikes tend do), the little added protection against minor touches is generally seen as not necessary. <S> Style: These things are ugly! <A> Are derailleur guards important? <S> Why does the more expensive bicycle (with higher component replacement costs if something breaks) not have one? <S> Is it correct that one cannot be installed on the one shown in the picture? <S> If it can be installed, is it recommended? <S> Are derailleur guards important? <S> Often a guard is on a bike geared toward kids or less experienced riders. <S> If you are likely to crash (or " ghost ride " your bike) then a guard may help. <S> If you don't crash then you don't need a guard. <S> Why does the more expensive bicycle not have one? <S> More expensive bikes are often marketed toward more experienced riders who - for the reasons listed in other answers - don't want the guard. <S> It may be seen as not needed and added weight. <S> Sometimes there is snobbery that prevents people from putting things like derailleur guards, kickstands, fenders, spoke protectors, reflectors, and other useful equipment on their bike. <S> It is possible to install a guard on the one shown in the picture? <S> It's possible to install a guard on any bike - even if it does not have bolt points - by using clamps as one option. <S> It's always easier to install a part that is actually made to go on a bike <S> but there are creative ways of attaching things to bikes. <S> If it can be installed is it recommended? <S> It depends on your situation. <S> If you need a little added protection on your derailleur <S> then I'd recommend it. <A> Not noted in the other, excellent answers: Inexpensive bikes have a tendency to not be well cared for - they're purchased by people who either need inexpensive transportation or for kids (who are notorious, as a group, for not taking good care of expensive things*). <S> More expensive bikes tend to be better cared for by riders who actually care about the bike they've purchased and would prefer not to have to replace unnecessarily damaged components. <S> When a casual rider of an inexpensive bike stops riding, he can often be seen simply dropping the bike to the ground and walking away <S> *. <S> If the bike happens to drop on the right side, the rear derailleur will hit the ground. <S> Even from the relatively low height of a rear derailleur, damage can ensue. <S> The derailleur protector can take significantly more hits than the derailleur itself can before damage build-up is enough to cause riding issues. <S> More serious riders of more expensive bikes rarely "drop" their bikes when they're done riding. <S> The bike is carefully balanced against a wall/tree/rock/etc to ensure that the precious componentry and paint job are not damaged. <S> If the bike is laid down flat, it will be laid on its left side precisely to avoid having either the front or rear derailleur come in contact with the ground. <S> * <S> These statements based upon personal observation of my own children not heeding parental instructions to not drop the bike when finished riding, and personal observation of other people treating their BSOs this way. <S> No offense intended to any casual rider who may happen to actually care for her bike. <A> One word KIDS, the little buggers love to jump off their bikes and let them crash to the floor, especially hard surfaces - these make perfect sense. <S> I am about to buy these for both of my kids bikes. <S> You can try to educate / plead with the ragamuffins or just pay the $10 and be done with it. <S> Pick your battles ......
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Also, more expensive bikes usually have exchangeable derailleur hangers that are supposed to be the first thing damaged in a crash (and, thus, prevent the more expensive derailleur from more damage).
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Is it possible to upgrade a rear derailleur with an other model, same company Shimano and the same speed I'm planning to upgrade my MBT bike for a real one, well entry-level. Talon 3 2019, which comes with these specs for shifters and derailleurs Shifters: Shimano Altus, 3x8 Front Derailleur: Shimano Altus Rear Derailleur: Shimano Acera I was thinking, maybe I could upgrade the rear derailleur Acera for this one : Shimano Deore SL RD-M591 SGS 8/9 Speed Rear. Is is possible or maybe Alivio ? Thanks I'm new to this world, I just love biking and the derailleurs make a huge difference, I want a good one! Thanks a lot <Q> Despite being marketed as a "9-speed" rear derailleur ( <S> the 9 referring to the number gears/sprockets/cogs--all mean the same thing--that make up your rear cassette), the M591 will work. <S> It is of a higher class/quality of components that Shimano named "Deore." <S> So this Deore derailleur will work with your 3x8 drivetrain because all Shimano 7, 8 & 9 speed rear derailleurs share the same "actuation ratio," meaning these rear derailleurs move the same amount per mm of cable pulled by the shifter. <S> Thus, your 8 speed shifter will pull an amount of cable to make an 8 speed spaced shift and the Deore will move the correct amount--the same amount the Acera or even a 7-speed, Tourney-class, rear derailleur would. <S> Especially if labor (your own or a bike shop's) to replace components is considered. <S> In addition, the trend in mountain biking is going to a 1x drivetrain (expressed, "one-by") <S> where there is a single chainring in the front and 10, 11 or 12 rear sprockets in the back. <S> This eliminates the weight and maintenence of a front derailleur and shifter, and two chain rings. <S> As your biking develops and you learn how u like to ride, open it up to different things. <S> Your derailleur upgrade is reasonable. <S> It will work. <S> One other thought is that you'll require the SGS caged (the longest option) M591. <S> While it's still the rear derailleur <S> we're discussing, the reason for needing a long cage (the lower part of a rear derailleur that houses the two small pulley wheels) is related to having a triple chainwheel up front. <S> There's more chain to take up and keep tight between the large ring and the small ring and rear derailleur's cage must be able to handle that range. <A> Jeffs question is technically correct, you could put a M591 derailleur on that bike. <S> However, the Deore M591 is a 2009 design and probably does not work better than the current M4000 Alvio range. <S> Also, shifting quality depends on the shifters and cassette as well as the derailleur <S> so it's questionable as to <S> wether you'd really see a benefit. <S> It's not cost effective to buy a bike then start replacing components. <S> Buy the bike that has the components you want in the first place. <S> What I would do in your position is spend a little more money and get a bike with mostly Alvio level components, or perhaps even Alvio/Deore mix. <A> The four issues you face when swapping rear derailers are number of gears pull ratio -- distance moved per unit of cable movement number of links that the derailer can "absorb" (and hence difference between min and max gear ratios) mounting scheme
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Replacing the Acera rear derailleur with the RD-M591 is possible. Conventional wisdom states that upgrading components on a new bike (& even more so, on a used bike) is more expensive than paying a little more for a bike that comes equipped with a higher class of components already.
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Bike spare parts in South America I'll soon start a rather long trip from Ushuaia in southern Argentina to Alaska in the north of North America. As I'm from Europe (France), I don't really know what to expect about spare parts for my bike in South America. I'll ride a Kona Rove ST, a gravel bike with 650b wheels and 47mm wide tubeless tires. The train is 1x11 SRAM. How easy do you think it will be to get new tires, gear parts, tubeless sealant and other spokes? <Q> I have around 1 year touring experience in South America. <S> Mostly remote dirt roads and trails. <S> I would never ever purposely run tubes again. <S> As long as you are confident in your tubeless setup flats should be almost nonexistent. <S> I only carry one tube for emergency that has never been used. <S> A small bottle of spare sealant is pretty essential to top off if you start to get small air leaks. <S> Needle and thread to sew small cuts, as well as tire plugs. <S> A few patches if you are forced to use a tube. <S> All decently large size cities in Chile and Argentina should be fairly well supplied with bike parts (somewhat less so in other countries in my experience). <S> If not, then it is usually easy to travel by bus somewhere bigger. <S> If you are in big cities (especially capital cities) can be good to stock up or change parts, especially if you are headed to remote areas. <S> Tubeless sealant is becoming more and more ubiquitous, especially in MTB communities. <S> Usually these guys are not running tubeless specific tires, and they make it work. <S> 650b mountain bike tires will be easier to find than road or gravel tires (could be an issue, not sure what tire clearance a kona rove has?). <S> Old shimano standards are king. <S> Dub and GXP bottom brackets/chainrings could be difficult (especially 1x). <S> I believe Peru only recently has an official SRAM importer. <S> Generally just keep an eye on parts. <S> Be religious about cleaning and oiling your chain. <S> Have a good idea for what is wearing and when you might need to replace it, and plan ahead. <A> I've just returned from several months touring in South + Central America. <S> I was running 700c and had difficulty finding decent tyres for this size (coudnt use 29er due to clearance issues). <S> Spare rims/hubs for anything upto 32h are also readily availible, however, as I found out in Mexico, spares for 36h wheels (rim/hub) are very hard to find, and only availible in major cities. <S> I was running 10 speed, gf running 9 speed - parts for these drive trains <S> were generally easy to get hold of. <S> I cannot comment on availibility of 11 speed components. <S> I would recomend taking a set of friction bar end shifters for emergency use of you break a gear shifter. <S> Definitly take some spare brake pads - these were very expensive (often 3 times the price in the UK). <S> Given they weigh very little, its worth taking some just for the cost savings, and they can also be hard to find outside of cities (depending on which ones you need). <S> I was using inner tubes, with several spare tubes on hand, and lots of patches! <S> I would usually get a puncture every 300-500 miles on average, although some days would see multiple flats. <S> I was glad I didnt go tubeless though, as my tyres picked up numerous cuts that definitly would not seal with sealant. <S> I also met other cyclist who were having issues with tubeless set ups and finding hard to find replacement sealant. <S> If you do go tubeless I would take at least 2 or 3 spare tubes for back up. <S> Make sure you know how to fix your bike before you head out, you need to be fairly self sufficient with bike maintenence. <S> For anyone from Europe, its hard to comprehend how remote some of these places are. <S> For example in Alaska and Canada, we regularly cycled several hundred miles between bike shops (on the Alcan), and there was no bus service or anything along this stretch. <S> Similarly for parts of Patagonia and Northern Argenina - we cycled several days between bike shops or larger towns. <S> Finally, if you do pickup a serious mechanical, most people drive pick-up trucks and its usally possible to hitch a ride to the next town. <S> Hitchhiking seems extreamely common in Argentina and Chile! <A> I suggest you plan your route through as many of the significant towns and cities as feasible. <S> Then google up the addresses of bike shops in each town, and save that list somehow with you, either on thin paper or on your phone. <S> And you should carry everything you'd need to do a basic roadside repair and maintenance. <S> Tools would be a decently specced multitool+chaintool, as well as cassette lockring tool and a lever for it (for spoke replacement). <S> For consumables, I'd suggest carrying this on your bike all the time:three tubes per bike, a pack of sticker patches, chain lube, one spare gear and one brake inner cable, four spare spokes and nipples, chain master links, and cable ties and some suitable spare bolts. <S> Perhaps one spare chain in the group for emergency. <S> Expect do a significant overhaul at least once on your trip, where you replace brake pads and all cables and so on, but that would be in a town or city not in a little one-pub town or worse on the side of the road.
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I would carry plenty of extra brake pads, they are light and depending on your brake model could be difficult to find. Tyres for 27.5" and 29er were the most common, and generally easy to find in cities or larger towns. SRAM parts can be much trickier to find than Shimano.
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Can my headtube take a tapered fork? I'm trying to replace a Suntour XCT fork on a '14 Cannondale Trail 4. I think it's a got a 1 1/8" straight headtube looking at the specs here: https://www.vitalmtb.com/product/guide/Bikes,3/Cannondale/Trail-29-4,13741 On Ebay all the forks seems to be tapered. I.e Rockshox Reba or Judy. Looking on CannondaleAnswers here - https://www.cannondaleanswers.com/definitive-guide-cannondale-frame-headset-fork-compatibility-for-mountain-bikes/ , it shows that a conversion is possible for some headsets with a KP205. The issue is I don't know what I have! the headset has 'Tange Seiki' on it. Does that mean its SI integrated? Anyway advice is greatly appreciated! we are both new to mountain biking so have very limited knowledge! Thanks. <Q> 'Tange Seiki' is just the headset manufacturer. <S> Reading this <S> https://www.cannondaleexperts.com/Si-Mountain-Headsets_c_1569.html <S> it seems that Cannondale SI Integrated headsets were used on Headshock and Lefty forks, <S> so there's no reason why your bike would have that type. <S> SI bearings are pressed directly into the frame so if you have separate bearing cups they are definitely straight 1 1/8. <A> There is a way to install tapered fork on some frames designed for "zero stack" 1 1/8" integrated headset. <S> Cane creek released in 2010 a headset that fitted in those frames and moved the bearing out of the head tube to make everything fit (see here ). <S> Quick google returned for example this headset . <S> I think this is will do the trick. <S> Best idea would be to visit your local bike shop and ask them to cross check with your bike at hand. <A> Becoming curious about your question, I looked up your bike on Bicycle Blue Book . <S> The specs listed here show the '14 Trail 4 to have a 1.5" straight headtube (see section on specs titled, "Frame"). <S> If this is so, then you can use forks with various combinations of steerer tube sizes like 1⅛ <S> " straight, 1.5" straight, or 1.5 to 1⅛ tapered. <S> This section from the Cannondale Answers website has the information and links that will clear a lot of things up regarding your options. <S> You need to measure the internal diameter of your headtube by removing the fork and, using calipers preferably, determine what size exactly is your bikes headtube. <S> If the internal diameter is 49.6 mm, you have a 1.5" headtube. <S> You may realize that 1.5" is 38.1 mm. <S> The additional 10.5 mm of diameter is utilized by bearing width. <S> It seems that you can more easily determine if your headtube is 1.5" by leaving everything together and measuring the height of the raw headtube. <S> If this measures 134.6 mm, it's likely you have a semi-integrated frame <S> (the cups for the bearings are machined into the frame, i.e. there are no external cups. <S> This information is outlined in the Cannondale link above. <S> Finally, if you find that your headtube is, in fact, 1 1/8" and your choice of steerer tube becomes limited, there is still a wide selection of suspension forks with threadless 1 1/8" straight steerer tubes. <S> While the tapered and oversized (1.5") steerers are taking over the market, my feeling is that 1 1/8" straight steerers remain the most commonly available option. <S> Utilize filters on your favorite bike parts <S> websites to limit the choices of suspension forks to those available with 1 1/8" straight steerers.
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These headtubes are 1.5" and are open to the variety of steerer tube diameters mentioned above when the appropriate headset is used. Also - pressing headset requires a dedicated press - unless you know what you are doing, it is a better idea to let bike shop do this.
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Busted my bike hub & derailleur (I think) - how bad is it? I screwed up :( Background leading to my foolishness: I've been straining my bike quite a bit with hills and inclimate weather, and I haven't been able to find my maintenance kit since I've moved, so in my busyness I've let myself push around on a squeaky rusting chain. I realize I may be learning an expensive lesson now. Today I kicked off and start pedaling, finding my chain was jammed up and not moving smoothly through a full rotation. That has happened before with a poorly oiled chain and I've pushed or shifted my way back into relatively-smooth operation. Well I pushed and it was stuck, not moving forward at all. Should've got off there but instead I pedaled backward a little, shifted and pushed, and it moved a little. That inspired me to push harder , and in my haste I pushed recklessly hard to pedal forward. Well, it stayed stuck and felt pretty wonky at that point, so I calmed down my haste and got off to check what's wrong. I found the back wheel had tilt/camber to it and the derailleur was bent out of alignment - I was definitely not getting anywhere quick anymore! I'll bring this to a local bikeshop ASAP to get repaired. Seeing what appears to be a weld severed, I'm not sure if this is a costly repair or a major overhaul I'm looking at. How bad are the damages, can you identify what specifically appears damaged and in need of repair? Is the frame and hub okay to keep and just needs a new derailleur? From a different angle: Rear wheel appears normal to me, no clear damage on axle, spokes, wheel frame or anything. I think the connection point for the rear wheel to the frame is what got busted in some way from my pushing, which led to the derailleur getting bent and the wheel off-camber. <Q> Updated based on your edits and comments. <S> The severed piece of metal circled in the 3rd image <S> is one of the cage plates, and was originally attached to the lower (idler) pulley bolt. <S> Beyond replacing the derailleur, there is no additional damage there. <S> Other items to check out, at least to verify that nothing else is broken: If you can spin the wheel and it rotates cleanly on the axle and is straight and the spokes are unbroken, straight, and under even tension then the wheel is good. <S> If the freewheel spins cleanly, and there are no bent teeth or wobble <S> then it is okay. <S> (Though if you're replacing the chain it may need replacing anyway depending on wear.) <S> Based on the way the derailleur bent <S> it's not likely <S> it damaged the freewheel, but it's still worth checking. <S> If the frame itself is not bent (the distance between the dropouts hasn't changed, they are still evenly vertical and level with one another, and the stays are all straight) then it's fine. <S> (If it's a steel bike then a small amount of bending is survivable, but if it's aluminium <S> it's trash.) <S> Obviously the derailleur is trash, but the derailleur hanger might be too. <S> (It's hard to tell from looking at the back side like this.) <S> You'll probably want the shop to make sure it's not twisted, which would cause the derailleur to mis-align. <S> You need a new chain, no question, since it sounds like a jammed link is part of the sequence that caused this. <A> How bad are the damages, can you identify what specifically appears damaged and in need of repair? <S> Is the frame and hub okay to keep and just needs a new derailleur? <S> From what I can see it's a derailleur replacement and <S> possibly a chain replacement - depending on how twisted the links are. <S> In the larger circle there are scrapes on the drop out <S> but I can't see an actual crack. <S> The smaller circle looks like the derailleur hanger - which is replaceable with the derailleur. <S> I don't see any hub issues. <A> The deraillier hanger(also called a frame saver)..did its job..its probably bent..and it looks like a mech, chain(cassette if worn or damaged) and inspection on hub and spokes.. and replacing as neccisary <S> .. <S> just the breakable(weak links) did there jobs just fine..if you haven't already buy a deraillier hanger alignment tool(I own the new wolftooth hat tool <S> and it's super easy and simple to get it setup right).. <S> I've found my hanger bent after even minor knocks.. <S> and I would also recommend carrying a spare one as if it does its job <S> right <S> it's likely to break off entirely.. <S> then you can get running after an accident(doesn't take a lot on yo <S> break them..) <S> The bolts for the hanger are just above the hanger itself .the <S> small recessed Allen bolts on the outside of the frame leg and threading into the hanger hold it on .. <S> just unbolt those to replace it(its likely compromised now <S> it's taken that much strain..) <S> ..I would recommend replacing it.. <S> it only costs £5-20 and are readily available..if your shop replaces it ask them to <S> but you a spare too <S> so you have it(plus the bolts to attach it..)
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It really does appear that you may only need to replace your derailleur (and chain). so in short I see no frame damage.. (If some of the spokes are deeply scored you may want to replace them anyway.)
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Should I adjust rear derailleur as my chain seems too close to each other I am learning to replace chain and freewheel (So far so good). After I put new freewheel and new chain on, the chain are too close to each other at the back now (as you can see in the photo). I think I need to adjust rear derailleur, is it right? Or maybe the chain wasn't installed correctly ( I cycled around and think chain install seems not too bad). <Q> The chain is too long. <S> All chains are sold with excess length and must be sized to the bike. <S> The length required depends on the length of the chainstays and size of the largest chainring and sprocket. <S> The easiest way to size the chain is making it the same length as the old chain. <S> You can also find the required length by putting the chain on the bike on the largest chainring and sprocket (and not through the derailleur). <S> This Park Tool video shows how it's done. <S> Update after getting info that the new chain was cut to length of old chain: <S> Don't just shorten the chain and see what happens, you need to follow the sizing procedure to make sure the length is right. <S> If the chain is too short for the large chainring/largest sprocket bad things will happen if you attempt to change into that combination. <S> Before you do that, check that your derailleur has enough total capacity for the chainrings and sprockets you have. <S> Your derailleur looks like a short cage version and may not be able to take up the chain slack necessary. <S> Total capacity needed is: (difference in teeth between largest/smallest chainrings) + (difference in teeth between largest/smallest sprockets) <S> If you have a Shimano derailleur you can look up the specs here . <S> Note there is a link to archive spec docs if you have an older model. <S> If you don't know what model you have or can't figure it out post a pic of the derailleur in your question, and tell us road or MTB and <S> how many cassette sprockets you have and someone will likely identify it for you. <A> Argenti's answer is correct - your chain is too long. <S> Personally I don't bother calculating the numbers from the manufacturer's specs. <S> I can generally assume that this combination of cassette/rear mech/chainring was built to work together, so its just a task of getting the chain the right length. <S> My method for sizing a chain when the old one is unavailable (or the wrong length) <S> Have the free ends hanging downward. <S> Use an old discarded spoke as a holder - bend a hook into each end and use it to hold the chain to length. <S> Something like this: Pull slack from the chain until the rear mech's bottom jockey wheel is cocked forward agressively. <S> Something like this (or perhaps even a little more) Then use your eyes to figure how much chain to remove, to join it and keep this angle. <S> REMOVE THE WIRE HOOK! <S> (guess how I know this.) <S> And finally give it a test change. <S> Your small-small combo should not end up as close as your initial photo. <S> Assuming you're not changing transmission components, most bikes will end up perfect this way. <S> You need exactly enough chain to run in Big-Big without binding, and the rear mech will take up the slack from all smaller combinations. <S> Save and label the take-off links in case you need to do some bodgery later to repair damaged links. <A> Too long..by a lot.. <S> I've got a 11-40 9 speed on a long cage with a 34-50 upfront..and my chain is scary long .. <S> but it's also just long <S> enough(1chains not enough I need 3 more links..) <S> ..it was like this when I lengthend it first time .. <S> took 1 link out and its fine has been since.. <S> Try big big (chainring and cassete)..not in deraillier..and then to the nearest pin <S> when pulled taught..and then plus 2 full links..never fails.. <S> I've fone this when a chain I swapped to a friends bike meant I had to resize my new chain.. <A> There is a formula some people use to calculate chain length. <S> Measure the length between the center of the bottom bracket and the center of the axle in inches. <S> Multiply by 2 and then add (the number of teeth on the largest chainring divided by 4 ) <S> plus (the number of teeth on the largest freewheel cog divided by 4 ) plus 1. <S> Round this total up to the nearest inch <S> and that is the total length of your chain in inches. <S> For a standard 1/2 x 3/32 inch chain There are 2 links per inch, so if you multiply the length by 2 it will give you the number of links you need. <A> From the photogoraph we can tell that although the derailleur is folded into an extreme situation, the chain around the jockey wheel is not yet making contact with the bottom straight run. <S> It might rub a bit when the chain shakes up and down. <S> If the derailleur only folds into that extreme configuration when you shift onto the smallest cog (highest gear in the rear) together with the smallest ring in the front (lowest gear), it's not necessarily a problem. <S> That's a nonsensical combination of gears that you wouldn't normally use, and if there is a tiny bit of a chain-on-chain rub in a nonsensical gear combination, it is of no consequence. <S> What you have to watch out for is that the chain is long enough when you simultaneously shift on the largest cog and ring. <S> If it isn't, that can be disastrous when the shift attempt is made. <S> Never shorten a chain without making sure it can fit that combination of gears.
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Wrap the chain around the big chainring and the biggest rear cog, and through the derailleur correctly. Presumably you did not cut it down to size it when you installed it.
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Front disc brake wobbling / grinding on pads after full braking and minor plunge The front disc brake grinds after a light accident with full braking and plunge. To give an idea of the forces involved: The bike fell to the left, mostly cushioned by me. The bike had no more linearmomentum. The brake lever and handlebar band has minor scratches. The handlebaror stem is slightly skewed. It look like the wheel/rim is not deformed/buckled , it's not visiblywobbling. The disc is slightly deformed, wobbling at most a couple of 100µm . Thebending cause by the pads looks more than a millimeter. The gaps between disc brake pads are not even , one pad is always touchingthe disc. The disc seems to be not centered in the brake. The handlebar is slightly skewed (de-justified stem/steer tube). The animation shows the brake photographed from the front toggling with brakereleased and slightly, but not fully pressed: From the animation you can see that the brake pads are not evenly spaced. On theleft (inner) side there's a (wide) gap, while on the right (outer) side the padis already touching the disc. Also, the disc is being pushed and bent by theouter pad moving. (Note that the animation was created from two photos taken with the bikestanding but being unfixated and the levers being operated. This causes someminor movement of the whole bike. If you think this makes the judgementimpossible, tell me and I'll try to make a better pair of pictures.) The animation shows the wheel spinning in 90° steps, photographed with sharp angle to (along) the fork: The wobbling is quite visible. There's no more than these scratches caused by the plunge: Technical data Gravel bike Carbon fork Through-axle Aluminium drop bar Shimano 105 BR-R7070 with dual pistons 1200 km driven, 4 months old Bike: 10 kg Saddle bag and water bottle: 3 kg Me including backpack: 65 kg Course of events This is after full braking and a - presumably - light plunge from standing. Thefront wheel locked, the rear wheel lifted off the ground. The bike was upside down (angled 45° - 90°) and I had the saddle in my spine before I fell fore- andsidewards. So I pushed downwards and sidewards (along the axle, not in driving direction)into the stem with my body weight and a bit remaining momentum. There probablywas torque by the fork into the axle. Questions and guidance Is is possible that the braking energy itself might have deformed the brake? deformed the disc? damaged the wheel hub? deformed/invisibly fractured the carbon fork? I'm pretty sure the bike pluging did no major damage. What was stressed most during braking ? What components shall I replace (apart from re-justifying) to be safe? Apart from asking a professional bicycle technican for an estimate, are therethings I can check for myself? Might the fork be damaged by the aforementioned forces? More background This happened during a light traffic accident. Ask for details Ask for details, more part numbers, measurements or other photos (i.e. of thescratches) if required to gauge this. If you think there's too much distractinginformation, tell me and I'll remove it. History of later clarifications/additions: Clarified: double pistons. Rephrased/deduplicated "Course of events" section. <Q> Two possibilities - the wheel itself have shifted, unlikely with a though axle though. <S> The crash does not seem to have be bad enough for a major damage like deformed hub to damaged carbon fork (Carbon is far tougher than many people make out and tends to fail catastrophically). <S> While the risk of damage might be slim, the consequences if the fork fails are about as bad as it gets. <S> Its likely that the caliper has taken a knock and shifted on its mounts. <S> All that will be required if this is the case is aligning the caliper. <S> Refer Park tools website for detailed instructions https://www.parktool.com/blog/repair-help/hydraulic-disc-brake-alignment <S> The short version is to loosen the caliper bolts, apply the brakes gently hile spinning the shell, as you tighten the bolts slowly and carefully. <S> This will center the caliper and and alight the pads with the disk. <A> Based on your description of the accident (thankfully it wasn't more severe to you or the bike), especially the lack of contact save the left sided ground landing, the odds are quite favorable that the carbon fork is unharmed structurally. <S> A carbon composite can become weakened if it's taken an impact which has broken the resin bond between fibers. <S> This delamination results in weakened areas as delamination can spread out from the area initially damaged. <S> I'll defer to others here to elucidate the physics involved, but generally, the braking forces acting upon the fork are concentrated along the forward, leading edge and the backside, trailing edge of the fork and it's steerer tube. <S> The absence of plasticity in carbon fiber means the fork---all carbon aspects of the fork if not full carbon--is in no way deformed from the powerful braking episode. <S> The presence of a thru axle was helpful to the scenario, allowing force to be spread over a larger area as well as diminishing potentially damaging twisting forces upon the fork. <S> Regarding the rotor: take it off and have it trued. <S> Reinstall and then go about the simple, straight forward process of realigning the caliper. <S> Here's a Park Tool article that covers the mechanical details that need to be taken to do those jobs. <S> A note about the caliper: certainly something significant could have affected the caliper because of the extreme braking instance <S> but it's much more likely to be unharmed. <S> Probably designed to tolerate far greater forces, the caliper wouldn't even wear out much faster if every brake activation generated the degree of force experienced here. <S> Finally, I offer you this q&a from this site that may guide you to the next steps to take in order to build confidence that all is well. <A> Thanks to Jeff and Matt for your thorough answers. <S> Here's a report of the repair ... <S> Repair results <S> After partially undoing the screws I realigned the brake by pulling the brake levers. <S> That did it already, the disc was not grinding anymore. <S> I had to spin the wheel and carefully brake it to a stop for proper realignment, static braking didn't do it. <S> The brake pads looked good, evenly worn and intact. <S> Then I checked the pistons. <S> They had a bit dust around them. <S> The caliper and pistons were cleaned using Q-tips, a towel and alcohol. <S> The pistons were pushed back in using a plastic tool. <S> I exercised them by braking and pushing them back. <S> After that they (still) moved evenly on both sides. <S> Screwing the through axle back in cause a squeaking sound and wasn't that easy. <S> I've cleaned the inside thread from minor burr with a brush and the axle was now happier. <S> The handlebar was realigned . <S> In the process I made two silly mistakes: <S> Using too much torque on the steering tube clamp bolts Not asking for clarification beforehand
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The emergency braking resulted in enough force to momentarily defeat gravity and begin a loaded rotation around the hub/rotor area, but carbon composite forks are designed (significantly, by direction of weave and thickness of laminate at fore and aft edges) to withstand far greater force than this. The brake was tightly bolted to the fork, the screws weren't loose at all. A small portion of the inside threads looked a bit "blunt" but not all of them. However, if you have concerns over the fork, get it checked by a bike shop.
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Can I use any screw for my derailleur limiters? I need new limit screws for my rear and front derailleur. Bike shop wants to charge $5 for them when they probably cost $0.05 each. Can I just get my own screws from the hardware store or do derailleurs require specific screws? If the former, what measurements/etc should I look for as far as the shaft and threads are concerned? Also, what kind of thread locker should I get? <Q> I was once quoted by a retail plumbing supplier $16 per "fancy screw" for a shower fitting, and needed 6 of them. <S> They were M3 grub screws with a pointed end, so not large. <S> Instead I went to a specialist bolt-and-fastener shop and got 10 of them for $0.48 each. <S> So your screws have certain parameters that must be met <S> Length <S> thickness <S> thread pitch <S> thread form <S> And some parameters that are optional, or variable. <S> Head format <S> - philips/JIS or flathead or hex head or torx, or a thumbscrew, or a bolt head.... <S> Make sure its some tool that is in your multitool Head width and depth - doesn't matter as long as you have enough room for it. <S> Material - Stainless Steel would be advisable, but other steels could be workable too. <S> Titanium may save a gram or so but would be expensive. <S> Aluminium is too weak for this application <S> For a B tension screw, the end that faces the frame is relatively unsupported, and should be approximately rounded off so it doesn't bear on the hanger with a sharp corner. <S> For Limit screws they press on steel lugs inside the mech. <S> Other than all that, any competent screw shop should be able to sort you out. <S> Only downsides are that they may be wholesalers who want to sell by the hundred or by the box/pack. <S> Also they may not do cash sales, so check first. <A> Based on the sizes listed on a couple of Shimano rear derailleurs, the limit screws (Shimano calls these "Stroke Adjusting Screws") are metric machine screws. <S> Specifically, M4 x around 18 mm. <S> M4 machine screws have 0.7 mm thread pitch and come with various types of heads (aka: caps) such as "hex socket head cap screw" or "flat head slotted cap screw" and others. <S> As far as length goes, it can vary between the high and low limits (the low limit is usually about 2 mm longer). <S> Some models of rear derailleur have identical lengths of limit screws (18 mm). <S> Note that it's often easier to obtain a screwdriver than a 3 mm Allen key though I find the socket head cap screws don't strip out near as easy nor does the tool slip out of the business end as easily as a screwdriver. <S> A well stocked hardware store or home improvement department store (Home Depot, Lowe's, Fleet Farm, et al) will have these metric machine screws in their screw bins. <S> They may be individual or packaged with 2-4 screws per package. <S> You should find the price per single screw around $1 and far less as quantity increases in a package. <S> Regarding length: this is easily adjusted by trimming excess length off a longer M4 screw with a hacksaw, rotary tool, or grinder. <S> Again, 18 mm appears to cover most rear derailleur limit screw lengths. <S> Thus, an M4 x 18 ... <S> cap screw is what you're looking for. <A> M3 and M4 are both in use for limit screws. <S> My favorite is to use a wicking threadlocker in this application, either Loctite 290 or Vibra-tite 150. <S> It tends to get really good penetration and works well when there have been problems with the screws working themselves loose. <S> You apply it after adjusting and it locks things up pretty rigidly, but not so much you can't adjust later.
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As noted in some comments, blue or purple (loctite 222) thread locker will help prevent the limit screws from moving on their own but still allows for adjustment of the screws with a hand tool. Obviously you can remove the current screws to determine the necessary length, and the type of head is personal preference.
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Putting smaller wheels on a larger frame I have a bmx bike that support 24 inch wheels, is their anyway I can move down to 20 inch? <Q> Putting small wheels on a bike designed for larger wheels will provide you with an array of design opportunities. <S> Here's a rough illustration of the objective <S> Let's go through some of the issues. <S> (not intended to be an exhaustive list) <S> Brakes <S> Pedal ground clearance <S> Chain ring ground clearance <S> Gearing Brakes <S> If the bike has rim brakes they would become inoperable with small wheels. <S> Options <S> - Go with coaster brake 20 inch wheels and only have rear brakes. <S> - Do some creative wielding and install brake mount points that would allow calipers / v brakes etc. <S> to function. <S> If the bike has disk brakes the best option would be to build disk brake 20 inch wheels. <S> Pedal ground clearance Smaller wheels put the pedals closer to the ground. <S> You'd need to find a crank that is short enough to provide the correct clearance. <S> If the pedals only hit on while turning you could learn to pedal only while going straight and keep the crank parallel to the ground while turning. <S> Chain ring ground clearance <S> Depending on what you start with this may not be a problem. <S> If you find that your chain ring hits you'd have to go with something smaller. <S> Gearing Smaller wheels have the effect of making all your gears lower and reducing your top speed. <S> This may not be a problem for your situation <S> but it's something to keep in mind. <S> A project like this is a great way to learn about the interaction of design choices. <A> Maybe, but you probably shouldn't. <S> If the bike is too large, changing the wheel size won't probably help, it affects mostly the steering and the "feel" of the bike. <S> If you are running brakeless then it might work without too much hassle, although ground clearance might be an issue when cornering. <S> The bike will look a bit whacky with smaller wheels. <S> If you have rim brakes and intend to run them, it's probably going to be more expensive to trying to get the wheel size to work properly instead of buying correct size bike. <A> I've recently learned of a style of road bike called a "minivelo" and its essentially a full sized road bike on 20" wheels. <S> Compare these two photos: <S> Common BTwin road bike - not expensive, and well found in the UK and EU. <S> BRUNO minivelo from Japan. <S> Notice that the top half of the bike is pretty similar, other than the angle of top tube which is more about styling and material minimisation. <S> The main differences come in the angles. <S> Notice that the seat stay is steeper, and the chain itself angles up significantly compared to the normal road bike. <S> This means the minivelo's rear axle is BELOW the BB axle, whereas its the other way around on a full-sized bike. <S> Also the head tube is slacker. <S> This is because the front forks are now shorter, and without some more rake (or "curve" forward), the trail will be much smaller leading to a twitchier ride. <S> Trail is what helps a bike self-center, and lack of trail means you have to actively hold it on center all the time, which is exhausting. <S> Even looking behind you while riding a trailless bike geometry is challenging. <S> Also, expect a bike with smaller wheels to get dirtier quicker, because its that much closer to the road surface. <S> One might think it wouldn't make much of a difference, but my 20" folder gets dirty way quicker than a 26" or 700c wheel bike.
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To effectively put smaller wheels on an existing bike frame, you'll have to make alterations to the frame to achieve these same results. - Rig disk brake mounts on the frame and build disk brake 20 inch wheels. If you cut the frame so that you can move the bottom bracket higher and then wield it all back together you can keep your current configuration. Another way to address ground clearance is with some creative frame modification.
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