source
stringlengths 620
29.3k
| target
stringlengths 12
1.24k
|
|---|---|
Is it possible to remove wheel without loosening the (V) brakes I have a mountain bike with V-brakes and every time I get a puncture and need to remove the wheel to replace the inner tube, I have to use a hex/Allen key to loosen the brakes, otherwise I can't pull the wheel out. Is there a way to loosen the brake arms without fiddling with the hex/Allen screw? I'm worried about wearing the screw out. Just to clarify, quick release isn't good anyway, noodle still won't come out and I still have to loosen the cable. Adding a photo of noodle in question, as suggested (I've moved the cover to the right to fully expose the end of the noodle): Another photo of noodle with breaks released: And one with breaks engaged (apologies for the blurriness, was a little tricky holding my phone and engaging the break): And finally, one with the arms pinched: <Q> Yeah. <S> Use the quick release. <S> If you push the brake arms together, you should be able to pull the noodle out of the noodle holder (you may need to wiggle it a bit out). <S> Then the arms will be wide enough to remove the wheel. <S> Alternatively, you can de-inflate <S> the tire, remove it and then re-inflate it after re-installation. <A> But if it is really necesary to have the cable so tight for the brakes to work, there may be some mismatch in the components or simply bad design. <S> Here are some tips that I have employed when using less-than-optimal v-brake sets: <S> Calibrate the system to need a fair amount of barrel adjuster deployed <S> so I can give the cable more slack, thus loosening the cable bolt is avoided. <S> I just have to re-adjust the barrel. <S> Remove and install the wheel with the tire deflated and squish it with my fingers to allow then to pass between the pads. <S> (Difficult if the tire is too wide and thick). <S> For a more temporary solution: Brake arms should be (nearly) parallel both in rest position and when applied. <S> Most Brake pads have some moveable spacers (washers) to allow them to protrude more or less towards the rim. <S> These spacers can be installed in the pad side or in the nut side of the supporting bolt. <S> (The spacers I'm referring to are flat on both sides, they can be added, removed, combined, etc. <S> to suit application).Someframe/rim combinations make the brake arms be in a divergent or convergent angle. <S> This is not the angle where the v-brake provides optimum leverage and also affects how much cable travel is needed to actuate the brakes and can lead to the problem described. <S> Change the noodle <S> : Use one that has a shorter tip, Such that it will require less cable slack to disengage the quick release. <S> A noodle is a very basic part, so even a generic will do. <S> Most likely the noodle tip is solid aluminium, but a soft alloy, so it can be shortened with a file or a fine grinding stone. <S> This should be made only as last resort and in removing as little material as possible as a too short noodle tip may get disengaged spontaneously on shaky trails. <A> Grip the arms together using your hand and you should be able to disengage the noodle from the quick release. <A> A shimano noodle can help you. <S> It have a "shortcut" to get it out of the holder. <A> Based on your fender/brake setup I think you might benefit from this: <S> http://problemsolversbike.com/products/travel_agents <S> The barrel adjuster (on the silver model) on the top could be tuned to do this with out tools. <S> So that instead of needing a 5mm to release the tension on the cable you could screw in the adjuster and bam, instant slack. <S> Just a thought... <A> You take one side of the tire off the wheel, pull the tube out and patch it, replace the tube (a bit of air in it makes it easier) and put the tire back. <S> This is a Dutch language video but with very clear pictures, front wheel but rear wheel works the same: http://www.hoe-doe-je-dat.nl/fiets/fietsband-plakken-video-tutorial.html
|
A properly tuned V-Brake system, assembled with proper, compatible components should let you disengage the quick release by just pressing the brake arms together with one hand and wiggling the noodle out. Alternative to the other suggestions, repair tube while the wheel is in place, with the break and all.
|
Force open a U-lock I have a kryptonite key opening u-lock, opening the lock had recently bocome stiff. But now the bike is locked outside and I can't turn the key the whole 180 degrees, only 90 degrees. It won't open. I've tried lubricating it and re aligning the discs. What's the easiest/ cheapest way of forcing it open? <Q> Angle grinder. <S> You should be able to cut through it in less than a minute. <S> Make sure to wear eye protection. <S> (source: machinemart.co.uk ) <A> Depending on where you are, consider having proof of ownership before you go dismantling a u-lock. <A> Try a shot of graphite or "lock lubricant" in the lock mechanism and jiggle the key for a bit before destroying the lock. <S> It may just be a bit rusty inside. <A> This is very location dependant, but police may remove it for you whithout charge, specially if it is locked to public urban furniture. <S> (I know a friend of mine got his bike back this way after losing his keys) <S> Of course you would need that proof of ownership. <A> Depends on which U-lock it is. <S> Something like the Kryptonite Keeper might be hacksaw-able efficiently, but you're going to have to do a lot more work with a hacksaw to take out something like the Fahgettiboutit. <S> Note that you'll need a blade which can cut steel. <S> Bolt cutters may also work on some U-locks. <S> And angle grinders. <S> Theres also using a locksmith.
|
Before destroying the u-lock, see if tapping it with a pipe or hammer in various spots while jiggling the key does the trick. If it's good and seized up, time to cut through it with an angle grinder. If you don't already have an angle grinder, Ryobi has some very inexpensive models.
|
bike grease got on my wall. best way to get it off? white paint on drywall. black bike grease. whoops. what are you tips and tricks for getting it off the wall/paint <Q> Probably best to start with something mild and work to more harsh until you find something that works. <S> It's probably also best to test in a non-conspicuous area on the same wall just in case something unexpected happens. <S> You can start with just soap and water, and see how that does. <S> Then try dish soap. <S> If that doesn't work, you could try the magic eraser things. <S> They do sell generic ones which people claim to work (never tried them) which could save money if you need to do this a lot. <S> I think these actually remove a thin layer of paint, <S> so you should probably be careful with these. <A> I'm using window cleaner and a clean rag (old shirt) to clean anything from painted walls. <S> If used carefully, it doesn't leave any marks. <A> I'd spray the area with a stain remover <S> /detergent something like vanish maybe add a little bicarb of soda for an extra bit of abrasiveness. <S> Then use a sander with a medium/fine grit sandpaper. <S> to get the grease off. <S> With a bit of luck you will not have to take it all the way down through the coats of paint. <S> Then once removed give it a good wipe down <S> I used this same technique on a painted/plastered internal wall during a house renovation that had some realllllly stubborn mould that even bleach wouldn't remove. <A> Try GooGone (citrus based) or dish soap. <S> In my experience one of those will get rid of the grease.
|
Window cleaner works like a combo of mild soap and alcohol solution – very effective against grease. If you do go too deep you can always do a little retouching (if you have matching paint)
|
How to fix a sluggish bike? I just bought a used mountain bike, and it seems to be slow. Pedaling seems like very hard work, and at a normal casual pedaling rate, I can only reach 4-5mph. If I pedal like I'm being chased by a lion I can get up to 10-11mph for a few seconds. For reference, I can run a 6-minute mile, so I can run faster than that. I'm thinking it's probably the bike, because the chain looks dirty and the wheels make scraping sounds as it moves. (I don't know if it's scraping against the brakes or something needs oil, etc.) How can I fix this? <Q> Since it's a new-to-you secondhand bike, for safety's sake as well as to deal with the sluggishness I recommend you take it to a bike shop for a complete overhaul. <S> I'll bet you'll be astounded at the difference when they're done. <A> At a minimum lube the chain and see what is scraping. <S> For the brakes just hold the bike up with one hand and spin the tire. <S> Visually inspect if the rim is rubbing on the brake. <S> Some times you can just adjust the brake and some times the wheel(s) need to be trued. <S> At this point need to decide if it is worth fixing. <S> Can the wheels even be trued? <S> A decent set of wheels is $200. <S> A good complete overhaul at a bike shop is over $100 and more like $200 <S> If you need new parts can easily get over $400 Get an idea of how much it will cost before you start spending money <S> If you don't want to spend money then - take off the tires and chain - put the wheels (without tires) back on - leave the brake released - <S> do the wheels spin freely - <S> does the crank (pedals) spin freely - <S> does the headset turn freely <S> At this point if things look okay <S> and you don't want to spend money then repack all (unsealed) bearings. <S> If you don't own any tools then probably not worth it. <S> If you need some new parts you will find out. <S> Add em up and see if it is worth it. <S> You are typically better off spending more money on a bike that does not need much maintenance. <A> I think that with a well-running bike you ought to be able to do three things: <S> The wheels ought to spin -- life each wheel in turn off the ground and set it spinning with your hand: it ought to spin and spin and spin almost without ever slowing down, almost frictionless <S> The tires shouldn't absorb energy -- that means you don't want knobbly tires because that takes energy, to deform the nobbles as you roll on them ... <S> racing tires are slick, and touring tires have some tread/grooves (but not nobbles) <S> ... also you want a kind of tire that expects to be inflated to more than 60 psi (and properly inflate them) <S> The drive train -- the chain should be lubricated etc and it shouldn't make a hardly any noise ... <S> no scraping or creaking or rubbing, mostly just ticking from the 'freewheel' hub. <A> First thing you can try is to disassemble and grease the bearings with the proper stuff. <S> To do that you have to do the following: 1) <S> Disassemble them as unscrewing the cones' contra nut and the cones themselves.2) <S> Wipe the old grease with something ( I am doing it with toilet paper ) <S> 3) Wipe every individual ball of the hub.4) <S> After everything is clean, put some grease on the hub's ball beds.5) <S> Keep doing that till you do the entire circle.6 <S> ) Pick up and place every one of the balls back on, so they can sick into the grease7) <S> Put the cap back on.8) <S> Screw the cones !! <S> BY HAND ! <S> ! <S> 9) Screw the contra-nut back on to hold it in place <S> After the procedure make sure that your rim is not playing around as you are trying to tilt it relative to the fork. <S> If it does - Unscrew the contra-nut and repeat points 8-9 till you get it right <S> :) <S> Repeat this thin on the both sides of the hub ! <S> Good luck !
|
Some times you have the tire rubbing on the brake. A cheap bike in need of a lot of maintenance is typically not a good value.
|
Is the plastic piece between the seven gear sprocket and the spokes hard to replace, and how? I was given a 21 gear mountain bike as payment for some work I did for a neighbor which had been in his backyard for about a year. Though it cleaned up very well there is one part I would love to replace: On the back rim, there's a plastic piece separating the seven gear sprocket and the spokes. It's pretty beat up. Is it hard to replace, and can you tell me how? I'm no bike mechanic, but have gotten my hands dirty. <Q> This is called the spoke guard and prevents the chain from getting tangled in the spokes if the rear derailleur is improperly adjusted. <S> Properly adjust your rear derailleur <S> and you will have no need for the spoke guard and can throw it away. <A> Since the guard is "beat up" it seems to have been doing it's job. <S> So the derailleur is, or was, out of adjustment. <S> Making sure the derailleur is properly adjusted is the first thing to do. <S> The next thing is to ride the bike for some weeks to see if it stays adjusted. <S> But if you have any doubts about it then keep it. <S> If the derailleur gets caught in the spokes then it can be ruined, along with a bunch of spokes. <S> Answering your direct question is difficult without a photo, because different tools are needed for different bikes. <S> So take it to a shop for this. <A> This is easy enough, but you'll need some basic hand tools, and either a cassette lockring tool OR a freewheel tool, and probably a chainwhip. <S> Drop the rear wheel from the bike. <S> Clean it (optional but makes everything else easier) <S> Remove the QR skewer or the wheel nut on the drive side. <S> Cogs removal: 4a. <S> Use the special tool to undo the cassette's lockring and then slide the cassette off. <S> 4b. <S> If you have a freehweel then its a different tool, and you spin the whole freewheel+cogs off. <S> Once that's clear you can see the plastic spoke protector which is often clipped to three or four of the spokes. <S> Unclip it and it will some right off, or snap in the process. <S> Either way its for the bin. <S> The new spoke protector should clip straight into place, even if its subtly different in design. <S> Reassemble is basically the reverse process. <A> Easy but you need a special tool for extracting the gears, and there is not a standard one <S> , brands have different, it is a job for a bike shop <S> , I'm afraid, but should be inexpensive
|
If the derailleur stays adjusted then you could remove the spoke guard rather than replace it.
|
Does riding a cyclo cross bike carry a large aerodynamic penalty when compared to a road bike? During club rides I find myself getting dropped by riders with the same weight and power but the main difference is that they are riding road bikes and I am on a cyclo cross bike (with road tyres and wheels). Is it my position on the cross bike or is it almost impossible to make a sensible decision with out knowing my co efficient of drag area? The current bike I have is a merida cyclocross 3 with cantilever brakes (pictured). <Q> On a cyclocross your CD (drag coefficient is not much different). <S> You are the same basic shape. <S> It is a little taller <S> so you have a bit more more frontal area <S> Are you sure you are the same weight and power? <S> Would any of them be willing to swap bikes and test. <S> I get dropped on rides on my street CX <S> but it is because I am just not as strong. <S> Based on your comment <S> I think you are confusing CD with area Drag = <S> CD x Area <S> x Velocity <S> x Velocity <S> If you are getting dropped while drafting as a team (they are not trying to drop you) <S> you cannot blame that on aerodynamics. <S> The guy(s) in the front have more more drag than you even if you are sitting a little taller. <S> If you are getting dropped you are not helping the team. <S> Take a shorter turn when you are in front. <S> Try and line up behind the next tallest rider. <A> It may not have anything to do with aerodynamics, but your gear ratio. <S> The website for the Merida Cyclocross 3 does not list the specifications, but the Merida 4 does indicate that, like most cyclocross bikes, it comes with a compact crankset, with the largest chainring at 46 teeth. <S> The compact cranks make going up hills a bit easier, but at higher speeds you will spin a faster rpm than typical cranks for the same speed, meaning you'll be working harder then the group and may tire out sooner, especially on flat to rolling terrain. <S> For the higher speeds, make sure you have an 11 tooth cog in the rear cassette and that will help (again, specs for the Merida 4 indicate 12-28). <S> You can find some more in-depth info googling: "compact cranks vs standard"also: <S> Why might a compact drivetrain be frowned upon? <A> In most circumstances you should not be getting dropped by riders your weight and power. <S> The advantage of drafting another cyclist is way beyond the differences in aerodynamics of your frame or brakes, even your position on the bike. <S> It would seem your problem is one of these: A serious problem with your bike (brakes binding, bearing resistance or rusty/gritty chain) <S> Your position on the crossbike is too upright resulting in you getting dropped in strong crosswinds (but not other conditions). <S> The other riders are stronger than you, allowing them to drop you in a sidewind or up a hill (situations what minimize your drafting advantage) A nocebo effect (the opposite of placebo) - you think you are at a disadvantage and give up earlier or are unconsciously unwilling to push yourself hard enough to hold their wheel. <A> I am in the same bandwagon, being dropped at high speed flat cruising, though I was looking for different suspects (pedals, clothes...). <S> For aerodynamics I would expect having broad shoulders or narrow, for instance, to have more effect than what road - CX differences can imply. <S> Even wider handlebars would have more significance than frame geometry differences (between road and CX that is) Since you say that you have similar power output, it could be performance when approaching or being in a glycogen depletion state. <S> I have marked this as the main reason of my dropping out the bunch, not sure if it can apply to you but think if the riders you go with are more used to long (60 miles and more) rides, and what is your average riding distance, and specially, can you follow them OK the first part of the ride or is it a no no from the beggining?
|
If you have this problem in a sidewind it might be your position on the crossbike is too upright. You should be able to stick with the group, but you will need to be spinning faster than you might be comfortable with.
|
How does increased upper-body strength affect riding, and which muscles make the biggest difference? I am a college student, in Air Force ROTC, and I bike for 1.5-3.5 hours a day. My cardio and core strength are great, but I haven't found the motivation to build my upper body. I'm a skinny build, so it will take some work. My question is: how will increased upper-body strength affect cycling, primarily all mountain and freeride type riding? On top of HOW more upper body strength affects riding, which upper-body muscles will make the biggest difference? <Q> For AM and FR (All Mountain and FreeRide) style riding, a strong upper torso is a huge improvement. <S> Like your lower body, you want a lot of it to be endurance as well as strength. <S> I have been on many a mountain bike ride in the spring after hours of snow riding in the winter (much closer to road riding) and had arms that were totally shot after only an hour or so while my legs were still quite fresh. <S> My personal feeling is that my shoulders and arms (uppers and forearms) seemed to be suffering the worst. <S> One of the main overlooked advantages of a strong upper body is being able to pump (like a pump track) while mountain riding to maintain speed. <S> I've seen strong BMX kids roll multiple laps around a pump track without pedaling at all, while a competitive road guy barely made a lap before his arms gave out. <S> Much of that can be translated to trail riding where you can use your upper body to extend your legs. <A> You need to develop your core as well as arms, so that's weights. <S> Don't forget your lower back as well - an area cyclists need stability, which comes from strength and endurance. <S> Handgrip exercises are good too. <A> More pedalling torque! <S> When you stand-up to pedal hard, your bodyweight alone is not enough. <S> You'll notice that you tend to pull up on the bars. <S> This allows you to push down on the pedals harder since you are no-longer limited by just your body-weight and gravity. <S> Look at world-class track-cyclists and you'll see they aren't just lower-body. <S> ;) <S> Stronger rowing muscles = more pedalling torque. <A> Upper body strength will increase your skills off-road. <S> Flicking the bike around will be that much easier. <S> Just because you're a "Skinny build <S> " doesn't mean that it's going to be a lot of work. <S> I know skinny 12-year-olds who can clear a 2' obstacle on their BMX bike. <S> If you want to build upper-body strength, ride a rigid bike on the trail. <A> Really, it's all about your core. <S> Your legs need leverage to push the pedals, and that comes from your core. <S> Crunches are probably the best exercise you can do to improve your cycling. <S> You help stabilize your core with your back and arms, so put a pull up bar in a doorway, and do pull ups. <S> That's all you need to do. <S> You definitely don't need to do a weight routine. <S> You don't even have to get fancy. <S> Back in the day when I was a serious cyclist, I was doing 200 crunches and 40 pull-ups almost every day. <S> Half in the morning, half in the evening. <S> That's a little extreme for most people, but I was a little extreme back then.
|
Riding BMX is also great for upper-body fitness. Keeping the front end straight and using your arms like shock absorbers as much as your legs will eventually take it's toll. One thing that hasn't been mentioned yet is the increased pedalling torque with stronger rowing muscles. Muscle bulk is not synonymous with muscle strength.
|
Are all side-pull road bicycle brakes compatible? I'm new to road bikes, but have been building mountain bikes for many years. I purchased a cheap road bike (at BSO price level) which I am upgrading for fun. I'd like to upgrade the brakes to something quality, as the brakes it came with barely slow me down. It has some side pull, single pivot generic brakes on it, and I'm wondering if I can upgrade to side pull dual pivot name brand brakes (Shimano 105/Ultegra or similar) without any other changes. Basically; are there things to check for that would make some side-pull cantilever road brakes non-compatible with any others? <Q> One thing to look out for is the size of the drop from the bolt securing the brake to the frame, and the brake blocks, to ensure the new brakes will fit in such a way that the blocks line up with the rims. <S> But it's worth making sure <S> they'll fit - more here: http://sheldonbrown.com/calipers.html#reach <S> I recently bought an old steel frame and had to get some long-reach calipers as my spares were all short-reach and the blocks would have clamped on the tyre, not the rims. <A> Well, 105/Ultegra are pretty high to put on a BSO or BSO priced thing (and the brakes will cost more than the BSO). <S> I'd probably go with 20 dollar Tektros. <S> Generally, they are all short-pull brakes so you should be fine with all of them. <S> Shimano has some New Super SLR cable pull, which you can pair with standard short pull brake levers , but Shimano wants you to buy new levers. <S> Also, note that the lever quality may also be low so you may just want to get new levers anyway. <A> You should see this page about installing and adjusting caliper brakes. <S> As others mentioned, look out for the reach. <S> Also, pay attention to whether you need recessed or traditional nutted mounts.
|
Probably if you have a newish bike, then any new brakes you buy will be of the same dimension as new brakes.
|
Why are spoke nipples called nipples? Does anyone know the etymology of the term 'spoke nipple'? The wiki page on Spoke Nipple and even google doesn't have the answer. Are there other threaded mechanical screws that are more like 'nipples'? Or did the end of spoked wheels at one point resemble nipples (say, for wooden wheels)? Why are they called 'nipples'? <Q> In plumbing and piping, a nipple is a fitting, consisting of a short piece of pipe, usually provided with a male pipe thread at each end, for connecting two other fittings. <S> - http://en.wikipedia.org/wiki/Nipple_%28plumbing%29 <S> This is from the wikipedia entry on the plumbing and piping context of the word Nipple as suggested by Daniel R. Hicks' comment. <S> Can anyone elaborate on the etymology of this, or why this term for short pieces of pipe was used for spoke ends (perhaps proper piping nipples were used in the past)? <A> <A> From the Online Etymology Dictionary: Nyppell, dating from the 1530s, for a protuberance of a mammalian breast where the milk duct terminates in females, as an alteration of Neble from the 1520s, itself likely a diminutive of Neb (beak), making it a little beak, or little projection. <S> The usage for small mechanical projections isn't attested before 1713, so the body part usage came first, while the usage for infant bottle teats didn't appear until 1875. <S> source: https://www.etymonline.com/word/nipple
|
I would guess that the etymology is by analogy – the closest existing hardware to a spoke nipple was/is a pipe nipple so that when wheel makers started looking for a name for the little thing with the threads that tensions the spokes someone thought that they looked a bit like tiny pipe nipples and the name stuck.
|
Trouble Removing bottom bracket. Is it my Tool? I'm having trouble removing my bottom bracket. I'm using quite a bit of force as far as I can tell. But neither side is budging. The bike is a 2011, and I've never removed the bottom bracket, but it's all aluminum, so I doubt the problem is with rust. It's quite difficult to keep the tool from slipping out. I've used this tool before on another bike without too many problems, but I just can't get it to work, and I don't want to strip the cups or do something destructive as this is my good bike. On the Park Tool website it says you can use a skewer to hold the tool in place if you have a hollow axle, but I don't have a hollow axle. I noticed that my tool works differently than the one on their site, and that the wrench is quite close into the bottom bracket. Mine mounts on a socket wrench, with a 1/2 adapter, and therefore is quite a bit out from the bottom bracket. There are pictures below to illustrate the situation. Update I was able to remove the non-drive side by using my vise grips to grip the tool closer to the bottom bracket. The drive side still won't move, but the vise grips are slipping, not the bottom bracket tool, so I think I may just replace the tools if they have something better at my local bike store. <Q> Assuming you've got the right direction you're turning and its still not budging, use some penetrating oil and/or borrow a breaker bar/vise (and use it carefully). <S> One of the things with your style of tool vs the park tool style of tool is that you can't get as much torque on. <S> In the case of aluminium, its conceivable that theres some corrosion, but dissolving it or heating it might be tricky depending on other types of materials involved. <A> So I ended up bringing the bike into the shop. <S> The friendly bike mechanic had let me borrow and old bottom bracket tool because they didn't have any other tools in stock. <S> Long story short, he ended up using a 6 foot pipe on his bottom bracket tool to get it to move. <S> The tool by itself did no good and the impact wrench did nothing. <S> I'm convinced the design of my bottom bracket tool is flawed. <A> A trick that not many people believe but works amazingly is to try and tighten a bolt/nut, or in this case BB before trying to loosen it, and repeating if necessary. <S> I assume this works as it breaks down corrosion or dirt, etc.
|
I tried holding the wrench as I turned it, and that let me put a little more force into it, but it still didn't work as well as it should. I think I'm going to buy a different tool that lets me get in closer to the bottom bracket as that was definitely the problem on the non drive side.
|
How to repaint a Carbon bike frame? I have recently purchased a Specialized Roubaix SL4 Elite Disc carbon frame bicycle - But I am not particularly happy with the colour. It is charcoal and white. I like to have a brighter colour.Is there a way to repaint a carbon frame or at least change the white pin stripe to a bright green. Thank you for your kind contribution. <Q> I'd avoid doing this. <S> However, since the sanding has to be done carefully (since its easy to destroy carbon fiber by sanding), you're going to end up paying someone a lot of money to do this (since it takes a lot of time to prep the frame). <S> You can't really use chemical strippers or other techniques that you'd apply for aluminum and steel frames can destroy the carbon fiber. <S> If you're really insistent on doing this, there are shops which specialize in repainting carbon fiber. <S> But, they'll charge you an arm and a leg due to the amount of labor they'll have to put in to prep the frame for repainting. <A> Check if Specialized will sell the pin stripe kit. <S> But I would not recommend it. <S> Tape over the old would be difficult and not sure it would stick. <S> Remove the old could damage the bike. <S> I would learn to like white. <S> Consider bright green bar tape, seat post, and saddle. <A> I would agree with batman that you don't want to paint it. <S> Instead, you can think of skinning it with adhesive film. <S> 3M and others sell series of stretchable adhesive films in various colors and textures that are used in the custom automobile and motorbike market. <S> They should be pliant enough to decorate your bike -- and if applied with care, won't be immediately visible as applied films. <A> There are companies that will plastic-wrap a car, its cheaper than a paint job and can be removed with no further damage to the skin. <S> The downside is that if you get a crack in your frame, you won't be able to see it through the plastic wrap, when you do your periodic maintenance. <S> Consider some coloured riding goggles if you want to change how it looks :-) <S> Answer: ride it as-is.
|
You also can't do things like powder coating for the paint step, since you have to heat the frame to the point where the carbon fiber can be destroyed. Basically, you do a light (typically wet) sanding by hand ( very carefully), prime it with an appropriate primer (maybe a few times) and then paint over it with an appropriate color.
|
Are rusty disc brake pads a worry? I'm the fool who didn't wash the snow off his bike - it's a rusty mess. I've just taken apart the front disc brake as it was rubbing. I think that was more to do with the disc being bent, but as I was doing it, I found the disc brake pads (?) are pretty rusty. This is what they look like: Should this concern me at all? Can I clean them up, or should I replace them? Or are they fine just to be left? <Q> Rust on the surfaces of the pads & disc could cause extra wear & noise, or if bad enough reduce the effectiveness of the brakes. <S> If there is enough present that you can see residue on your finger after rubbing the surface, I would suggest cleaning with a stiff bristled brush or a kitchen scrubber & isopropyl alcohol (some people have recommended automotive brake cleaner too). <S> There will probably still be some rust coloring on the pad, but it shouldn't be enough to cause a problem. <S> After cleaning, you should really inspect the metal around the pad too to make sure it is not corroded to the point that it may not fit the caliper right or could possibly break. <A> I think the rust on the pad surfaces will go away on its own when you use the brakes. <S> It's probably just a thin layer on the surface. <S> I don't think it hurts the brake disks, since rusted metal is softer than the original metal before rusting. <S> The rust on the backing material probably doesn't matter much either, since you were still able to remove the pads in their current rusty condition. <S> By the way, brakes on cars also rust <S> when they get wet and sit for a few days -- you can hear that they sound different the first time you use them after they got rusty. <S> But that doesn't seem to hurt them -- they still last for tens of thousands of miles. <S> I think the technology is similar to the disk brakes on your bike. <A> Rust or other build-up on your pads is not an issue if you have enough surface left. <S> Depending on the bran 1-2mm on either side is plenty. <S> If your brakes aren't biting properly clean the pads and rotors with rubbing alcohol. <S> Use an old toothbrush for the pads and a clean rag for the rotors. <A> If clean them and replace any bent discs and your problems go away, you're probably safe as long as you keep a close eye on things. <S> In other words, if your brakes are grippy, quiet, and smooth, a little rust never hurt anyone.
|
If you clean the pads with some brake cleaner and a brush and they just look rusty, it's not necessarily a problem provided your brakes are grippy and effective.
|
Pedals hits the ground too often while turning at relatively high speed I’ve been riding for 40+ years of which the last 25 I’ve ridden Specialized.Around April last year I decided to replace my old bike with a brand new Sirrus Sport, on an XL frame. While I love the looks and riding it, I have a serious safety concern. It has happened now multiple times that when I make a turn at a relatively high speed,the pedal hits the ground scaring the hell out of me. While this has happened in the pastwith other bikes, it has never happened to me this frequent, to the point that I don’t feel safe riding and turning at high speeds and that of course impacts my overall performance. I wonder if anyone has had the same experience with my exact same bike model. Could this be a Specialized design issue...? or could it be that whoever assembled the bike used the wrong stems or pedals...?I've got some pictures of the damaged pedals: I’d appreciate your feedback, or comments regarding how to fix this. I've contacted the place I bought the bike twice but I'm not getting an answer, perhaps I should try Specialized directly. <Q> The BB could be lower to improve handling <S> and I have definitely seen longer crankarms on large bikes. <S> A typical measurement is 175cm <S> but you could see 170 on a small frame or 180 on a larger frame. <S> The longer crankarm would be to accommodate your longer legs. <S> Look on the inside of the crankarm, you should see the length stamped in there, or you could measure from the center of the bottom bracket to the center of the hole where the pedals are. <S> I don't think it's an inherent design issue <S> but it could be a different design that doesn't work well with your riding style. <S> Side note: When cornering hard if you are going to have a foot down, you want your outside foot down. <S> This lets you keep your weight over the tires for maximum traction. <S> But, back to your original question, if you want to try and track down the issue, I would measure the bottom bracket height and look for/measure the crankarm length. <S> One or both of those measurements compared to your old bike would give you some insight. <A> Cornering at slow speeds is easy. <S> Cornering fast, that's where it starts getting harder. <S> You're getting pedal strike because your pedal is lower than the road surface, so consider not pedaling through the faster corners. <S> Instead, put your outside pedal down and put your weight on that leg. <S> IE, for a left turn you should be pressing on your right leg. <S> At the same time, unweight your saddle a little, a lot, or completely. <S> This does dual purpose of pressing the tyre's shoulder into the ground for more grip and less slide, and in your case keeps the pedal clear of the ground. <S> From <S> http://blog.artscyclery.com/technique/mountain-bike-cornering-skills-the-fundamentals/ <S> You can see how this chap has an exaggerated body position above the center-line of the bike. <S> From http://www.stickybottle.com/coaching/coaching-how-to-corner-fastest-when-racing-and-how-to-save-energy-in-sportives/ <S> A more road-bike photo. <S> Rider is not pedaling. <S> From http://www.bikeroar.com/tips/finding-flow-perfect-your-mountain-bike-cornering-technique <S> Again a slightly artificial photo, but it shows clearly the weighting on the outside pedal as well as looking right ready for the right turn. <A> Would you consider clipless pedals instead of clipped platform? <S> This is probably the most turning clearance for the dollar, second to replacing the crank arms with shorter ones. <S> A set of these pedals will improve your power output as you can pull harder on the upstrokes, as well as shaving probably ~1" or more off your pedal clearance. <S> One downside is that they are terrible to ride on without shoes designed to clip in, though some types (like SPD) have shoes with the clipless hardware recessed into the sole for easier walking. <A> Three options - or combination coast through the turn with pedals horizontal to the ground more narrow pedal <S> shorter crank arm
|
It's definitely possible that the bottom bracket height is lower than your previous bike and/or your crankarm length is longer. If you really want to continue to corner hard and fast you could ride hard in, drop the outside pedal, corner hard and then standup out of the corner and hammer on!
|
What causes frames to break at the (rear) dropouts? The drive-side dropout and rear axle have broken twice. It's an old-style freewheel, not a freehub+cassette. (I weigh around 100kg, and ride a lot, and have been touring on hilly, gravel roads, with 15kg camping gear on the rack.) The bike is an old (20-25 yo) hybrid Malvern Star (model "Elite"), steel frame, with 5 cogs on the back, and a freewheel. About 2-3 years ago, the drive side dropout broke, along with the rear axle (QR). I got new dropouts welded in, and the QR axle replaced with a solid bolt up (for $172 AUD).They told me the axle "wouldn't beak". After a year or so, the rear axle broke again (which the LBS replaced). Then, about 6 months after that, the drive-side dropout broke again ( EDIT near the chain stay) - not the weld, but the dropout itself, next to the weld. I ride everywhere, and did several wilderness touring trips during that time. They were "on-road", but hilly, gravel roads (Bunyip State Park), and sometimes they're corrugated, sometimes water eroded, and ther were some tree roots on a rail-trail once, which I (mostly) manage to avoid. I wouldn't think they'd stress the bike that much, and wheel rims are perfectly OK - even though single-walled. The LBS said it's because the freewheel stresses the axle, and when it breaks, the angle of the axle stresses the dropout, causing it to break in turn. They said it's the only cause of the break, and would not happen with a freehub and cassette. Researching online, I see the freewheel design does stress the axle. The guy now maintaining Sheldon's site agrees that that's how dropouts break; a couple of source only say it "can" break dropouts - but most don't mention an effect on dropouts at all. Is the freewheel why my drive-side dropout keeps breaking? Would a freehub + cassette really "solve" this problem, or would it keep happening? I want to go on longer tours, and don't want to get stranded! Is there another solution? Many thanks for reading all this! :-) tyres : Schwalbe endurance, 26x1.50, inflated to 100psi (which they are rated to). Supposedly somewhat puncture resistant; but I got one on every tour. dropouts : The replacements were forged dropouts (originals were pressed dropouts). It looks pretty strong to me, it's about 4mm where it broke, and about 7mm where the bolt goes. hubs : after second broken axle, LBS noted slight pitting on the hub where the ball bearings run. Wheels are "Joytech", new about 5 years ago. They were the cheapest ones ($80 AUD, IIRC), single alloy rims. They look very well made (to me). The rear was a QR. <Q> You already more or less answered your own question. <S> The reason is that in a freewheel hub the drive side bearing is close to the center of the axle. <S> This gives the forces from your weight and pedaling much more leverage to bend the axle than on a Shimano-style freehub where the drive side bearing is located at the end of the axle. <S> When the axle bends, it twists the dropout, which can also break. <S> Some other brands of freehubs solve the axle bending problem with a thick oversized axle. <S> This could work with a freewheel hub too, but I am not aware of anyone who makes that kind of hub. <A> When this happens all heck will break loose, and it's easy to believe there could be some collateral damage. <S> Once this has happened the first time, the hub (if not defective before) has likely been distorted to the point that it's almost certain to happen again. <S> I would say you need to replace the hub. <S> If not, it at least needs to be carefully inspected for damage, and the person assembling it needs to be doubly careful to get the lock nuts tight. <A> What kind of dropout did you have welded back in your frame when you had it repaired? <S> A higher quality dropout might be in order.
|
If the cone lock nuts on the axle are not set tight enough, it's possible (especially with a slightly bad or poorly lubricated bearing) for the (probably right) cone nut to be pulled tighter and tighter until either the bearing seizes or the axle snaps from the strain. My guess is that the rear hub is defective, or (at least for the first incident) was improperly assembled.
|
Headset fully tightened, but fork still loose and wobbly I'm almost done assembling my new bike :) There is still one thing in the way though... See the headset in the picture? It was installed by a professional (or, at least a LBS owner) when I bought the frame. Kinda came preinstalled. After assembling the bike, I went back to the shop to have the headset adjusted. And somehow they couldn't get the thing set up properly. I tried too, and yeah, let's face it, that headset is probably bad or badly installed. As is, the bike is pretty much unrideable since the fork would wobble every time I brake. The frame is an Intec M1, see document page 6. It has a 1" 1/8 fork tube. The current headset is a XLC A51AN. I guess it's an external headset, but not really sure. http://www.intec-bikes.de/index.php?eID=tx_nawsecuredl&u=0&file=fileadmin/Downloads/SecureDownloads/ra-co/ALLE/Sortiment/INTEC/INTEC_Katalog_2015_EN.pdf&t=1428962756&hash=d367558de1db3f45634191e466256d126c14beca There are enough spacers, allowing to tighten the top cap really hard, hard enough to almost lock the steering. Even then, the fork still wobbles. The fork tube is not cut straight, but I'm pretty sure the tube never touches the top cap. So what are my options to fix that? (not involving yet another LBS) What could explain why we can't adjust it? Can I fix this headset? otherwise, which tools would I need to replace the headset with another? And what kind of headset do I need? Also would I need to change the "fork race" (referring to the piece attached to the bottom of the fork tube, correct?) if I were to fit a different headset? <Q> The wobbling could come from the fork. <S> This is easy to check by putting a finger between two parts of the headset (as you can see here , around 0:35 ). <S> If you do, is the headset the correct size, BOTH for the frame and for the tube? <S> And are they in good shape? <S> These parts have low tolerances because they have to fit the frame and the fork tube very tightly, and different manufacturers have slight different dimensions. <S> If you can, go to your usual shop and ask them to test with another one headset. <S> Good luck. <S> And until you fix it, please don't ride that bike. <A> You don't mention the stem in your question. <S> If you tighten the topcap bolt without loosening the stem clamp, you won't be preloading the headset; instead you'll be crushing the spacers between the step and topcap. <A> See Emyr's answer above. <S> In a threadless headset (which is what is shown in the picture), the stem is what keeps the fork compressed into the head tube. <S> Then tighten the cap on top of the steer tube. <S> You have to make sure the cap is pushing down on the rings around the steer tube, not the steer tube itself. <S> Now tighten the bolts on the stem around the steer tube. <S> You can test the fork is installed by holding the front brake and rocking the bike back and forth. <S> If the fork is in there tight, you won't feel it move.
|
To make sure the stem is holding the fork in correctly, loosen the bolts that hold the stem to the steer tube of the fork. If you brake and feel movement, problem is for sure on the headset.
|
Can a Sora 9 speed rear derailleur short cage support a 12-36 cassette single chain ring 56T? My 20 inch folder has a single chain ring of 56T and a 11-28T cassette, 9 speed Shimano sora 9 speed Rear Derailleur short cage . I want to change the cassette to 12-36T for some hill routes. Based on my understanding the Derailleur capacity needed is biggest chain ring - smallest chain ring + (biggest cog - smallest cog) = 56 - 56 + (36 - 12) = 24. I am not sure the capacity of the short cage Sora 9 speed, because different source gave different info. And they all assume a double or triple crank set which is not the case here. So will my RD support a 12-36T cassette? <Q> I've done this. <S> You need to fit a small nut on the end of the longer B screw because the change in angle means the screw misses the frame. <S> the nut essentially widens the screw. <A> Not really. <S> A current short cage <S> Sora derailleur ( RD-3500-SS ) has the total capacity (i.e., 37 > 24), but does not support a maximum sprocket over 32. <S> Also see: How to calculate the capacity of a rear derailleur <A> While the capacity calculation you've done says OK, the max sprocket for a short cage road will be in the 20's or low 30's (in this case, its listed as 32t ). <S> Thus, I'd buy a long cage RD (or at least medium cage). <A> While using a Sora with a 36t cog may not be "approved" by Shimano, it's at least worth trying. <S> The real problem is getting clearance on the large cog, not the capacity of the derailleur. <S> This clearance is generally adjusted using the B screw derailleur adjustment. <S> http://sheldonbrown.com/derailer-adjustment.html#btension <S> If you are not able to use current derailleur with it's maximum B screw setting,what you can try is getting a longer version of that B screw and putting thederailluer even farther out. <S> As a temporary hack to see if this is worthwhile,you can put a small spacer in between the end of the B screw and the spot <S> whereit rests on the derailluer hanger cage. <S> This will at least let you know if it is possible. <S> I am reasonably sure that if the derailleur can work with a 32t cog, you can probably tweak it enough to work with a 36t cog. <S> If you absolutely can't make this work, then get a "short cage" Deore MTB 9 speed derailleur. <S> It has a long enough parallelogram and sufficent B screw adjustment to work with a 36t cog. <S> You don't need the long cage version of a derailleur. <S> You just need one with a sufficiently long parallelogram.
|
While the Sora short cage derailleur should be able it can take up the chain slack, the top jockey wheel may not properly clear the 36 tooth sprocket. Generally, with a 36T, you want a long cage (Shimano SGS), such as a Deore rear derailleur.
|
Kashima coat or not? I have some Fox Float 32 Evolution 140mm travel forks on my 2015 giant trance. I ride very aggressively and it's a bumpy ride down a lot of the tracks I do. Keep in mind I do technical tracks, over roots, drops etc.Today I rode a bike with 150mm pikes and I didn't feel a thing at all. I'm wondering if getting kashima coat on my forks would:1. Make them less bumpy (smoother)?2. How much would it cost?3. Would it just be more worth saving up for some pikes? Feel free to ask questions! Cheers <Q> I would Make sure your sag is set correctly. <S> See fork manual. <S> Place a zip-tie on your fork leg to act as a max-travel gauge, it lets you see how far from bottoming out you were on any ride and will aid you with tuning. <S> Play with the compression/rebound settings on your current fork. <S> If ride is too harsh, reduce both. <S> If you are unable to smooth out the ride, or it is at the expense of a wallowy ride, have them serviced (new oil, seals as needed etc). <S> Avoid large-bill outlays on the current fork while saving up for a better fork in case <S> you can't improve the ride enough. <S> You fork (and bike) will have some resale value, but putting money into it won't increase the resale value. <A> You have previously been able to purchase replacement Fox Kashima CSUs (crown/ steerer/ upper) that many companies will install as an aftermarket option on OEM forks. <S> Not that you would notice, as user2480585 has stated bumpiness of a ride <S> is generally a tune issue rather than a fork issue. <S> The 32 Evolution is a more than capable fork and if you were an advanced rider you're unlikely to feel the difference that the kashima coating would make. <S> A few years ago it was about $200 in the US but can't find much to verify that today. <S> I' don't think Pikes would be your best option unless you were looking to spend a bit more on the bike. <S> The Pikes are more at home on a more aggressive trail bike (Trance SX). <S> You can get a 140mm Pike on the SX <S> but I think you will find something else limiting the rest of you <S> 're bike as your riding gets more aggressive. <S> You find all kind of things to replace such as brakes, drive train, shock, wheels and cockpit chasing a more aggressive bike. <S> I would look to upgrade the whole bike rather than the fork. <A> As others wrote, first tune your fork, and keep it clean. <S> I use some silicon spray as well on the stanchion tubes and dust seals. <S> If you have coil spring in your fork (not air only), be sure it's for your weight - if not, swap it. <S> If still not satisfied, you can check <S> how low or high-end is the damper cartridge in your fork. <S> High-end dampers are more versatile, perform better on high speeds too. <S> My opinion is that "open oil bath" system forks are the smoothest, though not the lightest.
|
Cheaper forks can feel OK but not in a wide range of conditions.
|
Do I have to stop pedaling when shifting up the front chainring? If I keep pedaling when shifting up the front chainring, it would fail. Moreover, the chain keeps rubbing with the chainrings and produces many noises. Thus, I have to stop pedaling for around one second when shifting up. My bike comes with a 'Shimano Sora, band-type 34.9mm' front derailleur. The chainrings are 50/34T. I am new to road bike and don't know whether it is normal. I am not sure does it indicate wearing or misconfiguration. If it is normal, is the practice of stop pedaling the best technique when shifting up? <Q> Use the Clutch! <S> This is what I always tell people when I'm teaching them how to shift gears properly. <S> Chain-rings and Cogs are machined with *pickup points" that assist transferring the chain from one ring to the other, they only work while you're turning the cranks. <A> Completely stopping pedaling will not let you shift gears at all. <S> You do have to reduce the tension in the top of the chain to shift front, so pedal, but with small force. <S> The derailleur cannot push the chain sideways if it is under too much tension and thus pulled tight against the chainrings. <S> It is normal to reduce pedaling force when shifting. <A> As Sander already noted not turning the gears will not allow shifting at all. <S> Thus turning the pedals without really stressing them is key. <S> When shifting to a higher gear with such a system it might be necessary to firmly press the shifting lever when shifting the front gear up, or even shift twice if misconfigurated. <S> That stopping the pedaling helps for you might indicate that you are not shifting firmly and fast enough. <S> Otherwise it wouldn't have any effect. <A> It sounds like the front derailleur needs adjustment. <S> If that's the problem then it will take only a few minutes. <S> If it's worse, such a bent chain ring it will likely cost $$. <S> If you want to do it yourself, check out the front derailleur questions . <S> To change gears using derailleurs, you should continue pedaling. <S> Whether you need to pedal gently or not depends on the quality of the derailleurs and how well adjusted they are. <S> Certainly most cyclists have learned to pedal gently when changing, because of the painful consequences if the chain slips off. <S> With medium level equipment (such as Sora) and poorly adjusted equipment (such as yours currently) I would certainly ease the pedal pressure when changing.
|
So I tell people to let all the power off of their pedals, but keep the cranks turning and don't step back into the pedals with any force until the chain has fully shifted. If you recently bought the bike from a shop then take it back for adjustment.
|
Can I change from short to long derailleur to increase cog size I am have a tiagra 11-25 10 speed cassette with short cage. I am a poor climber and looking for extra gear; I would like to go 11-32 for this year until my climbing improves, will the short cage derailleur take a 32 teeth cog? If not what 10 speed derailleur is recommended? <Q> It doesn't look like you'd be able to use an 11-32T cassette at all with a 10-speed Tiagra rear derailleur. <S> From [Shimano's documentation] <S> ( http://bike.shimano.com/media/techdocs/content/cycle/SI/SI_5XN0A/SI-5XN0A-001-Eng_v1_m56577569830746860.pdf ), the largest sprocket that either the short cage or long cage version supports is 30T. <S> If you wanted to use their 12-30T tiagra cassette, you would need the long cage because the tooth difference has to be 16 teeth or less for the short cage, whereas the long cage supports a tooth difference up to 22 teeth. <S> The [11 speed Ultegra] <S> ( http://bike.shimano.com/content/sac-bike/en/home/road/shifting---braking/rear-derailleurs/rd-6800-gs.html ) derailleur looks like the only road derailleur from Shimano that would support an 11-32T cassette. <S> Incidentally, that's the derailleur that came stock on my 'cross bike <S> and it's got an 11-32T cassette on there. <A> The short and long deraileur cages each have a specified "capacity". <S> This capacity is the sum of the (largest cog - smalest cog) + (largest chainring - smallest chainring). <S> For example, if you have a tripple 30/39/52 tripple with that 11-32 cassette, you will need a deraileur capacity of (52-30)+(32-11)=43. <S> I don't think they make them that large - current Tiagara large is 39, but check on your model/year specifically. <S> With a 39 capacity deraileur cage, you can afford only 11 difference on the front, will only work with a 36-46 cyclocross style crank. <S> As the other answer stated, you will likely also need a new chain. <S> That being said, while it is not recommended, you could use a derailleur cage that falls a bit short on capacity as long as you avoid the small/small gear combos. <S> If you go this way, first make sure your chain is long enough to accommodate the large/large gear. <S> Then make sure you know which small/small gearcombos are going to be off limits by testing before riding the bike (or calculating from capacity), and make sure you NEVER try to use those gears. <S> Make sure you understand all this before proceeding, it is as I said not recommended. <S> I believe when the pros pull tricks like this for especially steep mountain stages, they are using a MTB derailleur or the cage from a MTB derailleur on their road derailleur - or the rider is just really confident he knows what he is doing. <A> You may need a longer derailleur, because you're going to need to run a longer chain to compensate for the extra teeth. <S> Whether it'll work or not depends entirely on gear ratios.
|
Try swapping the chain first to see if the new cassette work with the shorter derailleur arm, but you may find that the chain will be too long, sag, and rub on itself between the pulley cogs when you're riding on your smallest ring. If you really want to go up to 32T and stick with a road derailleur, it looks like you'll have to upgrade to the newer 11 speed stuff and get the long cage version.
|
Hydraulic disc brakes - total friction as a function of rotor size I have a hydraulic disc road bike with a 160mm rotor on the front and a 140mm on the rear. The setup is exactly the same front to rear, except for rotor size. I'd like to know the disparity between the force I would have to apply at the brake lever for the total friction or stopping power to be equal front to rear, for a given speed over a given distance, to a complete stop, i.e. total work done by each to be exactly equal. Since the 140mm rotor is 7/8th's the size of the 160mm, I'd be tempted to say that an equal lever pull would produce 7/8th's the friction on the rear, but I'm sure there is more to it than that. So, for example, If I'm riding at 10mph and come to a stop over 100ft, how hard would I have to pull each lever (as a ratio of front brake/rear brake) to ensure that my momentum is converted to exactly the same amount of heat by each rotor respectively? <Q> Don't worry about equal torque. <S> The front wheel will do as much as ninety percent of the work on a maximum stop. <S> You will learn to modulate the rear to prevent lock-up. <A> Braking is not a static operation. <S> The friction of any wheel is directly proportional to the weight currently being supported by that wheel. <S> As you brake the effective "weight" moves from the both wheels to almost entirely on the front wheel. <S> The harder you brake just the rear wheel, the sooner it willlock up. <S> Effective braking is not about absolute stopping power, but modulation. <S> Just about any brake can lock up a wheel, and once you lock up a wheel <S> your stopping distance isn't going to get any shorter[1] and you've lost a significant amount of controlon where the bike is going. <S> The point of larger disks is not to increaseabsolute stopping power but to increase control and heat dissipation. <S> The leverage difference between a 140mm and a 160mm rotor compared to the much larger diameter of the wheel is fairly minimal: 140/700 = <S> 0.2 <S> 160/700 = <S> 0.228 <S> A larger disk allows you to get closer to the lock up point and also suffers less brake fade due to heating. <S> In MTB jargon terms, a bigger rotor provides better "modulation", this means control of stopping power, not absolute stopping power. <S> The answer to your question is not a simple ratio, but a curve that is a solution to a relatively complex set of differential equations. <S> [1]- Depending on the surface, it may actually get longer. <A> Assuming the same force applied by the cylinder and the same materials, with the same pad size, the larger rotor will have a larger "lever arm" and be more "effective", in proportion to the diameter. <A> Your simple answer is essentially correct. <S> A hydraulic system is going to maintain a pretty constant mechanical advantage and frictional losses will be trifling. <S> So 8/7 more force on the rear will provide identical torques on each wheel provided <S> the pad friction response is linear,As pointed out, identical torques won't mean much as each wheel is under a different load. <S> Or to put it another way, so long as both wheels are maintaining road contact they will both decelerate at the same rate, regardless of which brake you are using... <A> While braking gently: Assuming identical hydraulics, pads and rotor material, friction will be linear with applied force. <S> The ratio will be about 7/8 (with larger rotor needing less force) with some adjustment for the fact that pads are not on the edge of the disc (making the difference somewhat larger). <S> This means that the rear wheel will slip under significantly lower braking power than the front (I hear it is by about 50% for common designs). <S> This means that under some conditions some levels of braking power achievable with the front brake will be impossible with the rear. <S> (A detailed discussion of how to balance and combine the use of the front and rear brake is outside the scope of this question.)
|
However, the larger disc is moving faster past the caliper, increasing the distance on which the friction acts and therefore braking power. But: Braking causes weight transfer - the rear wheel has a tendency to lift while the front carries more weight. Equal pressure will be fine for normal stops. There are some assumptions in your question that make it next to impossible to answer.
|
What's causing this puncture? This puncture is on the inside face of the tube. One day I got a big piece of glass in my tire. I patched it up and then I got a puncture on the inside face of the tube. I patched that and then I got another puncture on the inside within a few blocks. I patched that and then I got a third puncture on the inside within another few blocks. The punctures are not in the same place so I'm pretty sure the rim is not the issue. Do I have a piece of glass inside the tube, rolling around and puncturing in random places? Why are the holes only on the inside face of the tube? Will any new tube fall to the same fate? <Q> It looks like a glass cut to me. <S> It is common for glass to lurk in the tire case, so this is unusual. <S> Take the tire and tube off completely and inspect the inside of the rim and the tire carefully. <S> If you can't see anything, run your fingers around the rim and the tire. <S> If you still haven't found anything, take the rim tape off and check it and the rim again. <S> If you still haven't found anything, reassemble, sigh deeply, and hope for the best. <A> From your description, it sounds like the culprit that is causing the problem hasn't been cleared from the inside of the tire, so you may continue to get flats over and over. <S> At this point, I'd replace the tube at least, and possibly the tire as well. <S> Next time you need to replace a tube, make sure to slowly and carefully examine the inside of the tire with your fingers (being careful not to get any glass or splinters in yourself). <S> If you can't identify what's causing the flat from that, hold off on replacing the tube, because it will probably happen again, or, take it to a shop. <S> The other possibility is that you're not installing the tube properly and it's pinching when you inflate, causing a pinch flat. <S> Make sure everything is seated properly and that no section of the tube is bulging out of the tire before inflation. <A> This puncture made from outside - the glass isn't inside the tube, but did you get it out of the tire? <S> Is your tire intact? <S> Did you hear the tube blowing up? <S> It looks like your tire have something that punctures the tube. <S> It maybe a glass in it, or metal hoop that inside tire bead came out, or the tire sniped in some place. <S> As every time when you install the tube you rotate the tire, the puncture will be at another place on the tube. <A> Sounds like you have a spoke poking through, or causing a lump, in the rim tape. <S> Or there is damage to the rim tape or some other thing stuck to the rim tape or rim. <S> If you can't see of feel anything give the wheel a wash and scrub the rim. <S> Hope <S> this helps Mark <A> I have had the same baffling issue lately, and I still don't have a positive identification of the cause for the puncture: I just got the second puncture on the inside (toward the spokes) of the tube. <S> I have adhesive-backed cloth rim tape, so <S> I'm sure that's not moving; I installed the tube by hand, and I'm certain it wasn't kinked or nicked by a screw-driver, etc. <S> There was absolutely nothing in the tread or in the inside of the tire. <S> Two factors were common on both days I experience this kind of flat. <S> I had just topped up the air pressure to 90 psi, and the day was hot <S> (I live in Texas). <S> Today, I rode 17 miles to work on the tire in the morning with no problem. <S> Less than a quarter mile into the ride home in the afternoon, the tire went flat. <S> It was similar the last time, too. <S> I have to assume that getting out on very hot pavement (the asphalt was soft and melting in places) <S> caused the tire pressure to increase. <S> I'm not sure of the physics, but it's possible that that this would cause the tube to develop a hole in that location. <S> I think the solution in my case is to keep the tires inflated to a lower pressure (as measured cold by the tire gauge) when it's this hot out because the pavement is going to heat them up and increase the pressure.
|
If you didn't already, you need to clear the inside of the tire of whatever debris is causing the flat, before replacing the tube.
|
How to minimize damage from pitted cones? While working on a old 60's Raleigh I found that there is slight pitting on one of the cones on the front hub (rest of the hub is good). Ideally I would replace the damaged part and move one, but spare parts for these bikes are becoming difficult to find. While I did find a replacement this time, there may be a point that I will not. So given that one can't fix this properly, what can be done to ensure that damage is minimized? This will also cause my bearings to wear out faster, and rules of thumb to follow? In my case these are the oil lubed hubs and I plan on sticking with that, but if grease would work better, then I'm ok with that too. Here is all the damage the current cone has: <Q> I would recommend doing two things: Reassemble the hub with the thickest grease you can find (within reason). <S> It might slow you down a little, but it will help the bearings last as long as possible. <S> Make a mark on the back side of the cone that corresponds to where the damage is. <S> When you're putting the wheel on, rotate the axle so that the damaged side of the cone is facing up. <S> Then (assuming you adjusted the hub perfectly), there will be no pressure at all on the damaged side of the cone, and all the pressure on the good side. <A> "Ball bearings depend on the continuous presence of a very thin -millionths of an inch - film of lubricant between balls and races, and between the cage, bearing rings, and balls." <S> Pitting happen very often when user over-tighten the hub, or forget to re-adjust the hub between winter/summer (depends on where you live, in Scotland I need to give a proper re-adjustment every half a year); especially from Winter to Summer, if you have the hub adjusted in the winter for good fit. <S> This leads to little/no lubricant between the balls and the hub. <S> Use good quality Ball Bearing Use grease specifically designed for bearings. <S> So that you do not have to service the hub too often <S> I wouldn't go too far before seeing the picture of your cones to see what actually caused the failure of your hub. <S> Could you please upload a picture? <S> EDIT: <A> There is no way to minimize damage. <S> With all due respect to BSOrider, the assembly rotates so no matter what position the damaged portion is, it will have an affect on the bearings and races. <S> Pitted cones, races, and bearings need to be replaced period . <S> Old Raleigh 3 speeds are quite ubiquitous so some LBS is likely to have them. <S> That having been said, this is a Raleigh 3 speed, not a artificial heart. <S> The amount of precision here is not that crucial. <S> The North Vietnamese used these things on the Ho Chi Minh Trail during the War. <S> The main thing is stop reading your computer and ride.
|
from the picture, it looks like the cone is either (1) being installed incorrectly (pitting appears only on a particular side), (2) Over-loading or wrong handling, (3)less likely, but I will not rule-out, is that the cone is machined with defects: asymmetrical Until you can get replacement parts, pack it in plenty of grease.
|
How can I store my extra wheels on the wall efficiently, without hanging them by the rim? I have 5 pair of extra wheels, which I would like to store on the wall efficiently. I am a little skittish about storing them using the rim since some of them are carbon wheels and I don't want to risk scratches. Any suggestions? <Q> While I agree that there are no real risks to string your wheels by the rim, there are a number of DIY and commercial wall mounted racks for hanging wheels at the axle. <S> Wheelzrack makes one good option, and even integrates a storage shelf for shoes and helmets. <S> They support up to for sets of wheels, which may be a good option in your case. <S> Feedback sports used to offer a Wheel Arm system, which had a bolt-to-wall mounting option (note: the Wheel Arm is no longer listed on home page <S> but they sell alternate models). <S> These are designd for shop displays, but will work in the home as well, assuming your significant other is tolerant. :-) <S> Hope that is helpful. <A> As suggested by this answer , there's really no problem with hanging wheels or even an entire bike up by the rims. <S> It's a good idea to pad the hook to avoid scratches, but this should be easy enough with some cheap foam or even tape. <S> Failing that, a narrow shelf with some blocks either side of each wheel to stop them rolling away would work and take up little space. <S> To avoid touching the rims, you could loop this between the spokes and around the hub. <S> If the wall is rough, cover it with some cardboard or thin foam/rubber. <A> If they are QR hubs you could remove the skewer and pass a length of cord through the axle, then knot it, so that the wheel could be hung by the cord. <A> I have an old steel coffee-table leg screwed to the wall of my carport by the flanges at the top of the leg. <S> It holds about 6 random rims normally, and sticks out slightly upwards To get more space and protect the nicer aluminium ones <S> , I use a length of ribbon or soft rope like sash cord. <S> This goes around the rim and is tied in a loop with ~100 mm of slack. <S> Then the loop is hooked over the leg and left to hang. <S> Works well for me. <S> Advantage - soft cloth is in contact with the rim. <S> Downside - its still hanging by the rim. <S> Another option might be a frame somewhat more like a dishrack but for storing wheels? <S> Advantage - rims are protected Downside - you'll have to make it. <S> And it will chew up floor space unless you make a wall-mounted one. <S> Final thought - how about one of these cheap wheel stands for each one? <S> Advantage - Just buy them, no making required Downside - Floor space used up/clutter Plus <S> even cheap ones are $11-$12 US each which adds up. <A> Put them in wheel bags and simply hang the bags up. <S> Keeps wheels protected, clean and dust free. <S> That's what I do. <A> Another option, very simple DYI is to make a pair of clamps for each wheel, eg. <S> metal plates (spacers?) , big enough to drill two holes: one to put axle through and one to pass cord through. <S> Hang that cord on the hook or wherever you like. <A> You either need to use the axle or support from below if you are not wanting to hang from the rim. <S> If you're going to slide them on a skewer then the other answers have plenty of suggestions. <S> You could hold poles up with shelf brackets and since your wheels will be light anyway you could get several deep. <S> You could anchor the end of the poles to the ceiling too if need be. <A> HANG THEM BY THE RIMSeriously get some hooks with a rubber coating on the outside from something like home depot or lowes or Amazon. <S> then hang up the wheels. <S> YOU WILL NOT SCRATCH THE RIMS. <S> I hang my zipp 808 like this and they are fine. <S> Heck, they are fine even when they have a bike attached. <S> Look man I get beeing protective about the wheelset you just dropped hundreds of dollars on but you will waste more of your precious money or time if you don't go this route. <S> Thats my 2 cents. <S> Best of luck to you
|
I imagine you could even use a short loop of rope to hold a couple of wheels. If you're supporting from below, assuming you are leaning them against the wall then you need either a shelf or 2 poles perpendicular the the wall.
|
Is Ultegra 9 speed compatible with Sora 9 speed? I have a 1999 Specialized Allez Comp with original Ultegra 9 components (see description ). Things are starting to get old (e.g. right shifter doesn't work well). I think it is time to partially convert to Sora. But I have a few confirmation questions. Will Sora shifters work with the brakeset of my original bike? I have 2 Ultegra cassettes. Would I be able to mix an Ultegra 9 cassette with a Sora chain and chain rings? <Q> Yes, and Yes. <S> You can use any 9 speed Shimano road components in the drivetrain (crankset+chainrings with appropriate bb, chain, cassette, derailleurs) and the rear derailleur can be a <10 speed mountain derailleur as well. <S> The chain can be made by KMC/SRAM/Shimano/etc. <S> and the cassette can be Shimano/SRAM as well. <S> I'd also run new cables+cable housing in the process as well, obviously. <S> In fact, the shift from Ultegra to Sora in this case might make the bike feel even better (contrary to PeteH's comments). <S> This is due to trickle-down -- the features of old Tiagra/105/etc. <S> have slowly moved down to the lower levels, so you get the good ergonomics and stuff of new Sora. <S> As for a general thing, I'd probably just get any 9 speed Shimano/SRAM cassette in the future which has the spacing you like, as well as a SRAM/KMC chain for 9 speed (these come with quick links which are less annoying than the inane Shimano rivet). <S> I don't see the point in scoping out for Ultegra-grade parts for this bike unless it makes you feel good -- just a waste of money given the past 16 years of engineering, since people will be hawking them at higher prices for people who just have to have the complete set. <S> A Sora grade chain will be fine, though. <A> To directly answer your question, yes, 9 speed Ultegra is fully compatible with 9 speed Sora. <S> Since even Sora is shifting to 10 speed, though, it might be time to consider upgrading the entire group set to 10 or 11 speed, if only for future parts availability. <A> That said, have you considered having your current stuff professionally maintained by a good LBS? <S> I am riding a 1993 Shimano 105 groupset that has well over 100k miles on it <S> and it shifts just as crisp as it did when it only had 1k miles on it. <S> Make sure they not just adjust the derailleurs but also replace your cables, housing, cassette, the chainring if it's worn and soak everything in some degreaser. <S> You'll be surprised how much life you can get out of a well-maintained drivetrain.
|
As others have said: Yes, 9 speed Shimano gear is all interchangeable. Brifters will work fine and the cassettes will work fine.
|
Campagnolo Crank Compatibility 11 speed crank to 9 speed chain/deraillieur/shifters I need to replace my 9 Speed Campagnolo Racing T Crank with a new one which uses the power torque system. Is a 11 Speed Athena (or 10 speed Centaur) crank compatible with the racing t front dérailleur and the 9 speed Chorus shifters? http://www.campagnolo.com/WW/en/Components/athena_crankset Bike parts Campagnolo Chrous Ergopower 9-Speed Campagnolo Chrous Brakes Campagnolo raceing t Crank (needs to be replaced) Campagnolo raceing t front derailleur Campagnolo raceing t rear derailleur Campagnolo Chorus Cassette 9-Speed Campagnolo C9 Chain <Q> I have used Shimano 10 speed cranks with 9spd chain, derailluers and gears. <S> Without actually having tried it with the Campy components you list, I see no reason why it shouldn't work. <S> The interior dimensions are identical (i.e. 3/32 of an inch wide, 1/2 inch long). <S> The one issue you may run into is that the front chainrings may be slightly closer togetherthan a 9 speed crank. <S> The shifting may not be as precise and fast as an all 11 speed setup, but of all the parts of the drivetrain the front cranks are the least "speed specific" and the easiest to interchange. <A> The Centaur 10s crank will give you the closest-to-original performance but the problem areas are all around the width and overall design of the chain. <S> Whilst the post fromFred above is true insofar as it states that the external dimension of the chain is different, it neglects to say that because of that width difference, in addition to a difference in chain construction, the way that the front derailleur and the chain interact is different. <S> Occasionally the chain will "ride" or "float" when going from a big chainring to a smaller one, without cleanly engaging the teeth of the chainring. <S> Going "up", there is a problem in that the ramps on the chainrings are designed to engage the outer cage plate of the chain to help it "lift" - the 9s chain does not have flush rivets, they protrude slightly, so the upshift ramps don't work anything like as well - you can mitigate this by also changing the chain to a 10s Ultra Narrow chain and adjusting the FD with great care. <S> It is not a combination that we would advise, however. <S> As the main Campagnolo factory-appointed Warranty and Service Centre for the UK, we can assure you that the above answer is correct. <A> I've just replaced my Campag 9 speed Mirage 53/39 crankset with a Campag 11 speed Over Torque Carbon crankset with EXCELLENT results. <S> Shifts even more smoothly than the original. <S> Had to set the limiting screws off of the front derailleur to prevent the chain from being thrown of onto the crank arms during quick shifts. <S> Using a Record C9 chain and a Campag 13-28 9 speed cassette and original Mirage front derailleur and shifters <A> I have ridden several thousand kms on full 9-speed Campagnolo Veloce setup and more than 10k with otherwise same components but 10-speed Chorus crankset. <S> In my experience the mismatched set works far better than full Veloce 9 and does not have the problems described by Graeme. <S> That being said, I'd pick the 10 speed one since difference is smaller. <S> My guess is that chain and chainring design does not play a large part in this, but the fact that Veloce chainrings are pressed sheet metal and Chorus ones machined from thicker plate.
|
When you are using gear combos that involve the cross chaining on the small chainring, the extra width of 9 speed chain may catch on the larger chainring. The only difference between 9spd and 11 spd chain is the exterior width of the chain.
|
Lycra and hybrid bicycle I just went for a 50 mile ride on my hybrid (1/3 on an unpaved trail, 2/3 on a paved trail), and I am curious regarding the outfit I'm wearing. Is it frowned upon to wear a skin tight (road bike style) cycling clothing while riding a hybrid? Would I benefit from a more baggy outfit? What's the "traditional" hybrid outfit? <Q> I would say that it isn't very common to see people wearing Lycra on a hybrid. <S> However most people I see on hybrids wouldn't ride 80 km. <S> At that distance, the right clothes can make a real difference in energy expenditure and comfort. <S> The people who don't wear Lycra mostly don't know the benefits or feel too self-conscious to wear it. <S> I think that you should keep wearing Lycra if it makes you comfortable. <A> Not what you ride or what you wear. <S> Riding 80km is respectable, especially if 1/3 is on unpaved trails. <S> Let your legs do the talking. <A> About functionality of road bike kit <S> For distance riding there a number of functional advantages to road bike style clothing (road kit), these include: High quality chamois reduces the chance of saddle sores; <S> Tight fit reduces aerodynamic drag and effort at higher speeds; Sweat wicking properties keep you more comfortable; Tight fitting makes it easy to layer clothing to match environmental conditions; Tight fit keeps clothing from getting caught when moving around on the bike: <S> This is why XC racers wear tight kit as it keeps your shorts from getting caught on the saddle when you shift your weight behind a high saddle (i.e., riding drops or braking hard); and In Cyclocross (CX) <S> this makes mounting and dismounting much easier, as you literally step over the saddle and onto the pedals in one motion when mounting on the run. <S> Apart from (2) it is reasonably easy to find varying degrees of these features in other "baggy" style bicycle clothing. <S> If you are riding a lot of gravel then your average speed will be lower so (2) won't matter as much but <S> (5) could still be useful. <S> About Clothing Conventions <S> As others have commented on, if you like it, then that is all that matters. <S> If a roadie squawks tell them, "Life's hard, get a helmet!" <S> But in all seriousness the only places I would consider baggy wearing clothing over bike gear (to look more "normal") is areas of the world that have strong cultural identities that may clash with this type of clothing. <S> Sometimes this can lead to a short-circuit in the brain, causing behavioural problems. <S> I can think of some places in every continent of the world where this could be an issue. <A> I'd say that for any ride (or any other exercise) which is enough to need a shower and a change of clothes afterwards, you might as well wear appropriate gear. <S> I look slightly daft in lycra and feel uncomfortable going into the office, and also ride a hybrid. <S> When I had a commute of 40 minutes of fairly hard riding each way I went for bike leggings and a slightly-looser-than-skin-tight jersey (down to gym kit in warm weather) . <A> Be aware that there are biking clothes that don't make you look like a racer. <S> Plain black biking shorts and a solid 1 or 2 color biking/athletic shirt isn't going to make you look out of place on your chosen steed, but you will benefit. <S> My buddy does summer cross country bike tours dressed like that and he looks "normal". <S> I commute in jeans and t-shirts myself. <S> For longer rides, or warmer rides, I may go with some gym shorts for comfort. <A> If you are inclined to think about other people, social norms and <S> whats considered acceptable then Lycra is not the best clothing in some situations. <S> If you don't give a hoot what people think of you, lycra it is fine in most situations. <S> ( This comes to mind..... <S> Non- cyclists don't really cares about Lycra or not when you are on the bike (togs). <S> Its off the bike it counts when Lycra looks the same as underwear to most people (undies).
|
If you don't like the looks of the tight shorts, there are baggy cargo shorts made for biking as well. All that matters is that you ride.
|
Post race analysis of performance So I did my first bicycle race this weekend. The watts graph was very varied, there was a lot of low watt (150-200w) and short bursts of +400w. I would like to know how many bursts there where, and how long and what wattage they where on. Looking at the data in Strava I only see the 25w distribution or the maximum watt given a time (power curve). I don't want to do this manually. Are there any good tools for analysis of this sort? <Q> If you have a power meter than download something like Golden Cheetah to analyse the data. <S> Otherwise, if you are just using Strava's predictive data - I wouldn't bother as it won't be accurate enough for detailed analysis. <A> <A> While power analysis is useful (it is after all what gives you speed), at this early stage reviewing and learning from the race is more important. <S> Look at it this way: you can be the strongest rider but not win due to poor tactical decisions. <S> You don't mention the kind of race, so tactical advice can be misdirected ... <S> Consider <S> were there surges, and did you stay with them? <S> did you do a turn at the front, and how did that work out? <S> were you blown off the back? <S> was there a sprint finish, and were you in it? <S> were you beaten for speed, or endurance, and how do you think they are connected? <S> was there a point where people were consistently passing you, and why was that? <S> was there a time when you seemed to be in the wrong gear, or felt that you'd topped out? <S> Do work on your power output, and on understanding and extending what you can produce and for how far. <S> But learning racecraft so that you know when to push is equally important. <S> Also, check out posts by Rider_X on racing .
|
You could try looking at your ride through Veloviewer which offer a lot of very nice ways to dig into your data.
|
Should the hands be used for absorbing the impact after a jump? I am trying to learn some very small jumps and bunny-hops. It seems that upon landing from either, there are two options. I am talking here only about the moment of the impact with ground, and not about manoeuvring pre-jump or in the air. Upon landing, one can push with the handlebars down. This seems to have the advantage of delegating the work of absorbing the impact to the forks, which is what they are made for (assume hardtail). Alternatively, one can strive to stay centered on the bike, relaxing the hands, and absorbing most or all of the impact by the feet. This seems to be achieved by kicking downwards when the bike is just about to land. IS any of those techniques the correct approach? Or am I completely off? <Q> Your assumptions are wrong. <S> They do that so they can make room for the inevitable hand and feet compression which will happen when contacting the ground. <S> If you don't extend hands and feet then you only have: 40cm absorbtion of hands and feet compression 15cm absorbtion of fork and rear shock (on a 150mm travel bike) <S> 2cm absorbtion of tyre compression anything else is pain on the body and bike. <S> If you do extend the hands and feet just before touching the ground then you have: 80cm absorbtion of hands and feet compression 15cm absorbtion of fork and rear shock (on a 150mm travel bike) <S> 2cm absorbtion of tyre compression <S> This video shows an extreme landing at 1000fps <S> but it displays the extend-before-land technique very well: <A> If you watch a lot of trials riding, you'll notice they actually land with considerable more force on their rear wheels using their legs as a shock and then (sometimes even gently) touching down their front wheel. <S> Front suspension was mainly created to maintain control on rough terrain. <S> Trying to use your front suspension to absorb the impact of a jump requires that you put weight forward (or press down on the handlebars as you've pointed out). <S> Doing so however, means you are unweighting the rear of the bike and making yourself more prone to go over the handle bars. <S> For most of us, the majority of our weight will be on the rear of the bike, and the majority of our strength as well. <A> You want to stay centered. <S> Don't push the bars down. <S> But don't wait to kicking downwards when the bike is just about to land. <S> Extend in air smoothly <S> so you have room to absorb and get ready for landing. <S> On a hop you are trying to get air so you will be extended. <S> If it a jump you are tying to absorb you will be compressed so you will extend in air. <S> If you are not in the air very long it does not matter much - no kicking - smooth motions. <A> While not specifically addressing your question, this post from Lee McCormack addresses body position with jumping. <S> Between that post and others <S> he's put forth, the answer is: heavy feet and light hands. <S> i.e. don't absorb the jump with your hands/arms. <S> But you should use your legs to do the majority of the absorption (and rear suspension). <S> Which makes sense - would you rather jump off a table and land on your feet/legs or land on your hands/arms? <S> I suspect you'd answer with your feet/legs. <S> Also, look at BMX riders - fundamentally, their jumping is no different than MTB jumping, and the landing is all taken in by their legs. <S> Similar with trials biking as Chris in AK writes . <S> With front suspension you have a little leeway - but don't become dependent on it.
|
You use your arms and legs to adjust the bike to the landing (as the answer with the super-slow-mo video shows ) - getting front and back wheels to land at about the same time. Yes, riders do extend their hands and feet just before landing, but not to make the bike work more. You're better off using your front suspension to maintain control in your landing than using it to absorb the shock of the landing.
|
Best way to mount a big backpack to rack? Title says it all. I have a 65L backpack and would like to mount it on bike rack so it's most convenient to ride with and doesn't catch much air friction. Currently I'm doing this (sorry for the bad photo quality (it was intended to describe something else) but you can basically see it - putting the big backpack across the rack and securing it with two rubber straps): Problem is that the backpack of course isn't very stable and takes a lot of air friction. I'd like to fix the greatest possible amount of this. So, the question -- are there any better backpack mounting methods I didn't think of that would allow me to securely attach the backpack preferably in "vertical" or "lenghtwise parallel with the bike direction" position? Or, is there any equipment or special rack that would allow me to do that without some advanced rubber strap magic? :] Thanks a lot! <Q> I would suggest splitting the weight in half and putting it low on your bike for stability. <S> Here is my daily commuting configuration (2 matched 6 gallon plastic waste baskets mounted by hose clamps to a standard bike rack. ) <S> (Your emptied backpack could be rolled up and placed on top if you need it for off-bike use.) <A> This is more of an extended comment. <S> If you're mounting it on one side, that's likely to be quite a lot of weight off-centre, which will also affect the handling. <S> I'd aim for vertical, but you'll need something solid underneath to support the weight - like 2/3 of another rack inverted and bolted/clamped to your rack. <S> Alternatively you might get <S> this to work -- it's meant for baby buggies (strollers) and holds the weight quite long way back. <S> It might not be rated for your loads though. <S> The parent category of the linked site might be helpful for inspiration even if you're on the wrong continent. <S> You'd still need some serious strapping as well as a good way of keeping the rucksack straps out of your wheel (perhaps a rucksack cover on the wrong way round). <S> I suggest not having the load stick out much behind the back axle -- I've extended my rack backwards to mount panniers with a baby seat, and also used the buggy-mee I linked to above, and I found the centre of gravity so far back made the front wheel grip suffer (partially offset by carrying locks etc on the front forks). <A> Backpacks are intended and designed for backs. <S> I've biked with a tramping pack on and its not fun (modern ones tend to be too tall behind your head) <S> I'd go with a trailer. <S> Here's some ideas <S> These guys make single-wheel trailers and are well known. <S> http://www.bobgear.com/bike-trailers <S> They are "in line" and give the least frontal area increase. <S> https://www.biketrailershop.com/single-wheel-bike-trailers-e-158.html <S> Some trailers are built with the same size wheel as your bike, so you have a spare with you. <S> Some more "home made" approaches <S> http://www.cycletrailers.co.nz/html/catalog.html <S> Here's exactly what I mean <A> There is more than just air friction to consider. <S> If you extend the rack back then you would have too much weight aft and it would make the font wheel lite <S> (it may even bring it off the ground). <S> Vertical you don't have base size to secure <S> and now you have weight higher. <S> The bike would be wobbly. <S> You are not going to have a lot of speed. <S> I would go the current orientation for stability. <S> If you have steel rack you could weld in extensions. <S> You should go steel - <S> a Surly steel rack is like $140. <S> Not cheap but a trailer. <S> travoy Or even more money <S> a cargo bike like a Surly Big Dummy. .
|
I would pull some weight like bag / tent and strap it to the handle bar.
|
How accurate is the 'calories burned' figure on my GPS device? I use the Garmin Edge 200 to record the route, distance and speed of my rides. It also gives me a prediction of the amount of calories I have burned on any particular ride. The only data I have given it is my weight. It must use the speed and elevation GPS data to calculate a prediction but id like to know how accurate that can be if it doesn't take things like wind strength & direction, quality of surface and tyre type into consideration. As an example, I went for a 50km ride today and it informed me I burnt 1200 calories. Is this in the correct order of magnitude? <Q> By order of magnitude if you mean by a factor of 10 <S> then most likely yes. <S> You have wind, rolling, and gradient resistance. <S> It is going to be spot on for gradient resistance so if you have a hilly ride it will be more accurate. <S> Clearly it does not account for wind. <S> I expect it assumes a mid level road bike on decent pavement. <S> At speeds over 10 mph rolling resistance is the smallest of the three. <S> So it is going to be off on what is typically the smallest factor. <S> See the graph in the link: http://www.schwalbetires.com/tech_info/rolling_resistance <S> On a hilly road ride with no wind <S> it is probably with 10% overall. <S> Riding flats drafting in a group it is going to be off by a lot. <A> I'm using a Garmin 510 along with HR strap and Stages power meter on my road bike, and even with all that data I think it still over-estimates calories burned by nearly double. <S> I arrived at this figure based on tracking my body weight and calorie intake over many rides and months, taking into account hydration etc as well. <S> I'm 72kg, 9% body fat and a CAT2 racer doing 10+hrs/wk, and eat very cleanly. <S> Strava seems to derive an even higher calorie burn (~10%) than Garmin, but not consistently higher. <S> Overall I dont think these calorie burn numbers are worth using to manage energy intake or your weight. <S> I have no doubt that the accuracy varies hugely between individuals and circumstances due to variables such as body composition, metabolism, riding efficiency (a big one), temperature, sweat rates, diet and a whole bunch of other factors. <S> About the only value I see in calorie burn numbers from devices is bragging rights over coffee at the end of a big group ride:-) <A> Garmin has offered several different algorithms over the years to estimate energy expenditure and some are better than others. <S> is with a direct-force power meter, and -- in my experience, at least -- most simple algorithms to estimate calorie burn will overestimate the calories you've expended by 50% or more. <S> I've seen elsewhere that the range is typically between 20-25%, meaning that 75-80% of the energy you expend while cycling is not applied to the pedals and the remainder is. <S> Since there are 4 kJ per dietary calorie, the metabolic cost to you of applying 500 kJ of energy to your bike's drivetrain (i.e., averaging just under 280 W for 30 minutes) is thus likely to be somewhere between 500 and 625 kCal. <S> Unfortunately, the Edge 200 won't record power data even if you have a power meter. <S> This estimate still doesn't account for drafting and winds, but it uses grade, acceleration, your weight, and the weight of your equipment and is thus more accurate than estimates based on speed and athlete weight alone. <A> I have a Garmin 800 which includes heart rate in addition to speed and elevation. <S> It also knows my age, gender and weight, so with all that data it should be able to estimate calories burned pretty closely, or at least as closely as is possible outside a laboratory. <S> Well, according to my Garmin <S> I should lose almost 20 pounds every year during riding season. <S> Sadly, I must report that hasn't happened yet. <S> Not even close. <S> Yes, my calorie intake and levels of other activities during riding season remain the same, so if I'm burning, say, 3500 calories per week riding my bike like Garmin says, then I should be losing a pound a week, give or take <S> *. <S> In practice, though, I find that I lose maybe 5 pounds over the entire season, which is 75% less than Garmin predicted. <S> I say "give or take" because weight loss and calories aren't a simple equation. <S> I therefore conclude that Garmin and the other half-dozen fitness apps/gizmos I've tried all grossly exaggerate calorie usage. <S> Why? <S> Because looking at your expensive gizmo and seeing a huge number of calories burned makes you happy and sells more product. <S> So, based on my admittedly casual and anecdotal observations, I would recommend subtracting 50-75% from whatever Garmin says for a reasonably accurate estimate of calorie burn. <A> In my opinion it is only a usable value data point to compare against the same previous data point. <S> An unfit person will burn more calories at a given level of exercise (based on heart rate and other factors) than a fit person. <S> An unfit person will have a less efficient heart and circulatory system. <S> A calorie usage point can't be made without calculating the level of exertion.
|
However, the only way to get really reliable calorie burn data from a bike computer Heart rate tells it what my actual level of effort is, so that should take wind and all those other variables into account. There are dozens of variables involved and no two people are the same, but the margin of error should be somewhere in the 10-20% range, or at least less than 50%, and definitely not the 75% error I see consistently. Trail riding it is going to be off by a lot. If you want a better approximation of your energy expenditure, you might consider looking at something like Strava's estimated power instead. Unlike many other endurance sports (running, swimming, cross-country skiing), most people's efficiency while cycling falls into an extremely narrow range .
|
Best kind of bicycle for lower back issues? I've ridden bikes all my life. Now nearing 50, for the past year or two I've noticed that when I ride over 20km or so, my lower back gets extremely painful - enough to make it not possible to ride. The bike is the same one I've already had, so it's not a bike-fit issue. Because the bike is breaking down, I need to replace it. I'm worried about getting a bike that I won't be able to ride for anything other than short commutes because of back pain...and not finding this out until the first 20km+ ride. A short test ride of a new bike isn't going to be enough to determine whether it will trigger pain. Knowing that it's the lower back, what style of bike should I consider? I currently have a mountain bike and am thinking either of a touring bike or hybrid. I probably don't have storage space for a recumbent. Oh, and current bike is a mountain bike. In the past I did heaps of touring on it, with no issues. Now I use it for commuting, and sub-20km rides. <Q> I have a touring bike <S> and I find it quite comfortable. <S> But them again, I don't have back issues. <S> It's a bit more upright than most road bikes, and possibly more upright than some hybrids I've seen, as long as I'm riding on the hoods. <S> Spending $100 renting a few different models for a few hours at a time could save you a lot of money and help you find a bike that's comfortable for you. <A> Just because you've ridden the same bike for years does not mean it fits you. <S> For example a slightly incorrect fit could be causing the problem. <S> So what used to fit may not fit now. <S> Another cause of back pain is low core strength. <S> Do look into this one. <S> The third thing to consider is gearing. <S> Perhaps you're trying to pedal too hard, especially before you're thoroughly warmed up. <S> This is easily overcome by using a higher cadence, or to look at it another way, use a lower gear. <S> Get a sports medicine person involved, such as a physiotherapist. <S> Some of them can do the bike fit as well as diagnose causes and treat symptoms. <A> I have two suggestions: <S> It sounds obvious but look at the angle of your back in your normalriding position and consider going more vertical. <S> Proper fit for atime trial racer and vs. somebody who wants to get around town andget some exercise will give vastly different angles. <S> Try a recumbent. <S> These put you in an aero position and the seatback lets you push hard against the pedals yet <S> it's very easy on the back. <S> I was lucky enough to demo one for three weeks and really enjoyed the change. <S> At the time I was looking for an urban bike and a recumbent wasn't ideal for slicing between traffic and parked cars or hopping curbs when needed. <S> Years ago I went from a pretty aggressive riding position on a drop bar bike to a more level flat bar road bike and the stiff necks I used to have completely went away. <S> Totally worth it. <S> Since then many manufacturers have come out with more relaxed, "endurance" geometries.
|
Try to find a place that rents bikes or will let you have an extended trial ride in order to determine if it would help fix your issues. So I would definitely recommend a professional bike fitting. Perhaps you're trying to be too quick on those short rides. There are multiple causes of back pain; it's the most common human ailment, and the solution is unlikely to be simply given in an Internet forum answer. And your body can change over time; perhaps you've gained some weight, or lost some flexibly.
|
Rear cassette 'ticking' forward, making chain catch, what is the problem and how do I solve it? I have a Giant Rapid 4, bought in 2009. When freewheeling (i.e. rolling forward but not pedalling) on my bicycle, the chain catches. I had a look and I think this is because the rear cassette sometimes gets 'caught' slightly and moves with the wheel. This doesn't seem to be a problem when pedalling, but when I am not pedalling and the front gears are not moving, the chain catches. It actually broke my chain. Just put a new chain on, but I'm reluctant to ride it until this problem is resolved fully, otherwise the new chain will be stressed and may break again. So, what could cause the rear cassette to be 'carried' forward by the wheel? Is it a bearings problem, or do I need a new cassette? Thanks. Edit. I took off the cassette and dismantled the hub, it was the freehub body which was broken. It sounded and felt like one of the bearings inside it was broken. However the Shimano freehub disassembly tool is no longer sold and I couldn't find one second hand. The rim was worn anyway so I treated myself to new wheels and reused the old cassette, which was still ok. <Q> Most likely the free hub is sticking. <S> The grease can get old and sticky. <S> Service the hub. <S> Lots of videos on youtube. <S> Or take the hub to a shop. <S> Sticky hub is not likely to break a chain but it is a problem that needs to be corrected. <A> One of the pawls in your freehub is broken. <S> It happened to me once. <S> After riding up a steep hill, I noticed that my chain would sag and jump as the freehub would stick at different spots. <S> I took the freehub apart, and found that one of the pawls had broken in half. <S> Thick/old grease would not cause a freehub to behave like that, let alone breaking the chain. <S> So yes, you need a new freehub :( <A> Depends on your budget. <S> I'd try serving the freehub properly by opening it and cleaning it, or quick and nasty by flooding it with petrol for a day then dry it, and then squirt lube in. <S> Either way if it doesn't work, you're up for a new freehub. <S> Your chain is new which is great, probably a good time to inspect the cassette for wear too. <S> Do update the question and tell us what you ended up doing.... <S> this helps future searchers.
|
And you can wear out a hub - some parts are serviceable.
|
Is having a disc brake on a single speed bicycle a bad idea? I talked to a bike shop that sells a lot of fixed/single speed bikes. I asked them if they could sell me a single speed with a disc brake on the front. The guys said no because: It will be hard to find a frame that supports that It is silly and not really needed and a waste of my money If he is correct about the money part, then what would be a better place to put that money? I bit of background: I commute year round, and I really like the stopping power i get on my mountain bike (with disc) during the winter / rain. I also tend to ride 20-25mph in Boston. <Q> Well, there are lot's and lot's of commuter bikes with internal hubs and disk brakes. <S> I see no reason why a single speed wouldn't work as well. <S> A google search for "single speed cx bike disk brakes" turns up this beauty. <S> http://allcitycycles.com/bikes/nature_boy_disc <S> There are low budget models out there as well. <S> Nashbar 29'r <S> If you're going to commute in the rain,my opinion is that a disk brake is well worth the extra expense. <S> I'd go to a different bike shop. <A> Brake not break. <S> That said front disc brake is not a frame thing. <S> Just install a front fork that will take a disc brake. <S> Doubt anyone is going to have an off the rack that way as it violates the karma thing. <S> It is a money thing as it is (likely) a custom build. <S> You are going to find SS disc in cylcocross (CX) <S> as there is SS heat and disc is common in CX. <S> You will get a bike designed for CX with front and rear disc, knobby tires, and geared for CX. <S> It can be a nice commuter bike <S> but it will not be the same geometry as a street fixie / SS. <S> You are not going to find many CX bikes under $1000 new as they are selling to the racing crowd. <S> If you really just want disc you are seeing them more and more on street bikes but you are not going to find (many) SS (outside CX). <S> Look at something like a Salsa Collosal. <S> You won't find disc on race bikes as UCI does not allow it. <S> You will find disc on cheaper mtn bikes as mtn bikes are pretty much expected to have disc any more. <A> As others have said, simply purchase a fork that will accept a disc mount. <S> There will be some initial cost to set it up <S> but you'll save money in the long run just in wheels alone. <S> I would certainly suggest another shop to have the work done or a different mechanic at that shop <S> , it would have taken them 15 minutes to get you a list of forks and options from their vendors and then to write you an estimate. <S> If you're going to make the conversion to disc, consider going hydraulic; very responsive which is a huge plus when you're hauling buns thru traffic like you do. <S> The nice thing about a single speed is that there aren't a lot of other places to put the money if you already have a sound frame. <S> You'll need a new front wheel so you can get the rotor mounted <S> but wheels are where a lot of folks focus their money in single/fixed categories. <S> And of course the saddle, your butt is worth every penny. <A> I own a Surly Steamroller, and although I haven't done it myself, many other Steamroller riders put a Surly Disk Trucker fork into the Steamroller frame. <S> With the exception of the fork altering the geometry ever so slightly, it's a pretty like-for-like switch. <S> It's also a fairly inexpensive option. <S> You can pick the frames up for sub £200 and the forks for a good way under £100 in the UK. <S> Then build up with whatever parts you fancy.
|
A disc brake kind of violates the whole minimalist single speed karma. Getting exactly what you want will likely cost a bit more, but that should befor you to decide if it is worth it. On road you are not going to find disc on cheaper bikes as disc is not the standard. Single Speed Swobo makes one, you can build a Surly Straggler up as a single speed.
|
Grocery Shopping by bike, expanding my cargo options cheaply Can I take a shopping cart like say this one and safely attach it to a bike? I'd like to also take it into the store with me as well. <Q> I think you would be much better off converting an old kids trailer . <S> They can be found pretty cheap on Craigslist. <A> These will be a lot more stable than any home made conversion of something that was never designed to go faster than slow walking pace. <A> For my daily commute and for moderate sized weekly grocery trips I use two waste baskets, permanently mounted, each with 6 gallon capacity. <S> They serve as waterproof hard shells into which I can insert any bags, backpacks, clothes etc, that I want. <A> They are a little cumbersome to load <S> but I can fit a lot of stuff. <S> You can't fit a week's worth of groceries for a family of 5, though, so it depends on your situation. <S> For a solution more elegant for shopping, you can buy square-shaped shopping panniers which will more easily allow you to carry canvas shopping bags full of groceries. <S> These are very popular in Holland where bikes are a primary mode of transit. <S> ( http://dutchbikeshop.ie/wp-content/uploads/wp-checkout/images/fastrider-pannier-cargo-1423825156.jpg ) <S> One word of caution for most bikes in the US-- <S> you'll have to watch out for heel clearance with a square bag like this. <S> If you're serious about hauling a lot of stuff <S> then you should get a cargo bike, like the Surly Big Dummy or something with a frame-mounted front rack (Workcycles). <A> There are several manufacturers who offer rod supported quick connect pannier bags which you can easily detach from your bikes rear rack, shop and load them, then rehook to the bike and ride home. <S> They work great and are inexpensive. <S> One such company is Performance Bicycle. <A> I agree with Blams comment, I don't think you would want to pull that cart behind a bike. <S> Since you still want to take it into the store, maybe use that cart & mount it on a flatbed trailer with bungee cords. <S> Something like this maybe: http://www.burley.com/page_453/flatbedsuptmsup <A> Many grocery stores do deliveries. <S> There's also taxis. <S> About once a month plan a big trip and get a list of all the heavy, non-perishables items you will need. <S> This will include canned goods, frozen meats and vegetables, dried goods like pasta or rice, and other non food items like laundry soap. <S> The other stuff you need to bet fresh doesn't weigh that much. <S> Exceptions are things like milk, but sometimes I make a special trip just for that. <S> It's an excuse to ride my bike more, and I just go to the corner store because it's only a short trip, and it's the same price everywhere. <S> Also, learn to shop light. <S> Don't buy liquids like pop or juice. <S> Water is healthier anyway and comes right out of a pipe fed into your house. <S> If you want juice, try frozen concentrate. <S> You'll spend money on deliveries, about $8 a shot here, but you won't have to buy a trailer, and surely your bike will appreciate not having to tow heavy loads.
|
I go grocery shopping with my bike all the time, I put groceries in touring panniers mounted on a rear rack. There are trailers in a similar form factor, like the Burley Travoy (no recommendation, just the first I found), that are made for the purpose. Living without a car and having to get groceries for my family has taught me that bicycles aren't always the best solution.
|
Identify my Motobécane racing bike I bought a Motobécane last year (pics below), and now that the bottom bracket is broken, I really need to know the model of the bike, to help me change that piece. It would also be helpful if someone could redirect me to the Motobécane catalogs of the years 82, 83, I can't find them, and I suspect my bike is from this period. Technical specifications: frame color: green and black (How customizable was that? I think they didn't sell the same colors each year) frame: tubing inexternal 707, "trainer" (I don't find the appropriate info about it) brakes: Weinmann derailleur: Sachs - Huret. 12 gears Wheel: Maillard Bottom Crank: ?? width of the shell: 74mm. From this page http://sheldonbrown.com/vrbn-g-n.html , the old french ones have special dimensions. Also on Motobécane, they are swiss type (left-threaded). I don't know if this is a cotterless one, shimano octalink, or if I can put something more standard? [EDIT: As suggested by @Blam, I took the bottom bracket out.First mistake: shell width doesn't correspond to the red line on the pic, but less, so width should be 68mm, I'll double check on the bike.The Brand is Stronglight, french brand, but the threading is the normal one (left-threaded on the right side, and right-threaded on the left side).The axle is 120mm long, tapered square. Like this model: http://www.ebay.com/itm/VP-Components-Bottom-Bracket-120mm-Square-Taper-Unsealed-Bike-NEW-/311359596201?pt=LH_DefaultDomain_0&hash=item487e7a66a9 But anyway, I'm still interested in knowing the model of this bike, and/or finding the Motobécane catalogues of years 1982-83] Important Note: The rear wheel is not the original (was broken). I also changed the part of the crank where I put the feet when I bought it (maybe I shouldn't have...). Sorry if it looks quite dirty, I didn't have time to clean. Pics: <Q> I don't know the exact model (probably is Trainer as shown on the top tube decal) <S> but it was likely built sometime right around 1984, most likely 1984-1986 judging by the parts. <S> They went bankrupt in 1981 and were bought by the Japanese (Yamaha or Suzuki, I forget which) who relaunched the brand in 1984 as MBK (like many other French bike companies, they made more than just bikes - see also Peugeot). <S> The other giveaway is the Sachs-Huret rear derailleur. <S> Sachs and Huret were separate companies - one German, one French - prior to 1980. <S> In 1987 they introduced an indexing system to keep up with SIS which had come out the year prior from Shimano and was a massive hit. <S> In the late 90s the combined company was bought by the American SRAM company. <S> The shift levers look to be friction so that dates them to after the Sachs/Huret merger but before the advent of indexed shifting. <S> It is an entry level bike. <S> The big giveaway is the tubing decal which says "Hi Tensile". <S> Pretty much the same stuff used in Huffy and other department store bikes. <S> That said, not all Hi-Ten is created equal and there are actually some Hi-Ten frames that ride quite nicely even if it's far from being the lightest tubing. <S> As you've probably discovered by now the bottom bracket is a regular taper with English threads. <S> Most French bike companies stopped using French threads in the late 70s/ <S> early 80s much to the relief of bike shop mechanics everywhere! <A> Small correction, my mistake should have read " "MBK Trainer" on the down tube " .. <S> (but with a Motobecane Badge on the Steerer, some also with Motobecane in smaller letters on the top tube). <S> Checked a couple of the searches I had, you truly have a confounding model. <S> Hi-Ten, Cro-Mo, Motolite, 2040 <S> , one states Vitus tubes, but I can't read the sticker to verify it. <S> Some with proper lugs on the steerer, some with "inexternal". <S> I wonder if they were using up stock, after many of the older established models were discontinued after 84. <S> Fwiw, as long as you are happy with the weight and feel of the bike, nothing wrong with Hi-Ten. <S> As long as I'm only on paved surfaces, I still enjoy loaded touring with a 76 Super Mirage with lowly 1020 tubing. <S> The only bike I've always kept, still very comfortable at the end of long days in the saddle. <S> Many report good result with the BSA BBs for stripped threads. <S> Mine was in need and was lucky and found one incorrectly listed as French on the bay, I hope I will never need another. <S> Geo <A> Here's a partial answer (how to deal with the bottom bracket, not what bike it is): <S> The easiest solution (and likely best) is to buy the universal bottom bracket from Velo Orange (or similar). <S> These basically expand to fit in, and don't affect or use the threads so they'll work on most standard BB road bike frames. <S> It will be JIS (square taper). <S> There is some more information at this link . <S> I wouldn't bother trying non-square taper -- you're likely not to find a way to fit anything else in. <S> Phil Wood will cost a lot of money, but Velo Orange will be around 40-50 bucks for the right threading (and around 70 for the universal). <S> Then, just buy your favorite square taper crankset <S> (there are still a lot of good ones on the market) and go to town. <A> Turbulent times for Motobecane. <S> You can find the (last that I have found) <S> French Motobecane for 1985-6 <S> (dated Sept. 85) on <S> forum.tontonvelo.com <S> (with the French model designations). <S> However, no Trainer in them <S> and there are not many models <S> listed - MBK/Motobecane was producing many other models many with older tube types from the past (decals similar to Peugoet - later with red/orange/yellow colors) during 85-6. <S> The Motobecane name appears to have been dropped late 1986 the same year Yamaha became the main shareholder. <S> I suspect your Trainer is one of the earlier ones possibly late 85/early 86, <S> the later "Trainers" I've seen have either a "Reseau Motobecane" badge on the steerer tube or "MBK Motobecane" on the down tube. <S> If you check the components and the serial numbers with data on the web, you should be able to get a good idea. <S> I stumbled on a few sources out there on the Motobecane/MBK Trainer when searching for info on another bike of that period. <S> Recently got caught up into this period as well due to a Motobecane "Ranger" (no MBK on the frame) from the same period, picked it up for the missing Espace bars on a 1984 Mt. Becane. <S> Oddly and apprently the MBK label had already been used for the "Mt. Becane" in 85 (MBK model=Ranger) with the same specs as the '84 Motobecane (with the platform tandem fork and Espace handlebars through 86), the same time Motobecane Ranger was made with a different frame and unicorn fork. <S> The later 1987 MBK Ranger model looks the same as the earlier Motobecane Ranger including the unicrown fork. <S> All very odd. <S> Hope <S> this helps and good luck!Geo
|
Hi Tensile (or Hi-Ten) is the lowest grade of tubing used in bikes. The brand was known as Motobecane for most of their history. If you want to match the original threading, you'll likely have to buy from Phil Wood or Velo Orange and end up with a square taper anyway. Nicer level Motobecanes of the era would have been made using Reynolds 531 or various grades of Vitus steel tubing. Motobecane stared phasing out the Swiss BBs in the early eighties, you are lucky not to have one, tough to find and expensive, the Mirage unfortunately does.
|
Just bought 30 huffys cranbrooks for a bike rental business. WHAT PROBLEMS SHOULD I BE PREPARING FOR Be nice. I know these things are cheap. Just wanna be semi prepared. <Q> Forty years ago Huffy bikes were actually pretty well made, just heavy, ugly, and not very nimble. <S> But now that everything is made in China, as cheaply as possible, it's hard to predict the quality. <S> First off, you need to keep the tires properly inflated. <S> This is a seemingly trivial but incredibly important (and often overlooked) maintenance item. <S> Also set up a schedule to check every bike for such items as bearing play (both hubs, crank, and headset) and chain slack at regular intervals. <S> And squirt a bit of oil on the chains at regular intervals. <S> Otherwise, wait to see what breaks. <S> A lot will depend on how your customers treat the bikes. <S> Be prepared for some bikes to be destroyed, and for others to disintegrate on their own. <S> Expect to use damaged bikes as "organ donors" for repair parts for more serviceable bikes. <S> The Park Tools website and Sheldon Brown's site are your friends. <S> (I do wonder what provision you have for adjusting seat height. <S> You may need to invest in quick release adjusters for the seats.) <A> I've seen wheel bearings that were way too tight, so when you lift the wheel off the ground and spin it, it stops quickly. <S> This means that when people ride the bikes, the bearings wear out quickly. <S> Same thing for the headset (steering bearings), although probably not as critical, but easier to adjust. <A> If the bikes have a problem that causes them not to go, that can be lived with. <S> But if they have a problem which causes them not to STOP, somebody could DIE. <S> Most of your customers will not make any impact on the brake pads, but some will push the bikes hard, deliberately ride up and down hills, maybe in the rain - under such circumstances set of brake pads which you can still see the lines when renting out can become worn out completely in a single rental period, also causing damage to the wheel rims, not to mention legal problems in case of an accident. <S> When you start replacing the worn brake pads, you might consider upgrading to other than the cheapest option, because they give a better usage-time/cost ratio.
|
Those bikes have the cheapest brake pads possible which might wear out very quickly, depending how they are used. I would start out by checking all the bearings and adjusting them. In my (limited) experience with cheap bikes, the people that assemble them don't care at all if they do it right.
|
How can I stop my toes from going numb on long rides? I've begun trying to commute to work, which is a 70+ minute ride each way for me. I find that after about 30 minutes of riding, my toes in both feet begin to go numb. It's not a cold thing, because it happens in warm weather too. It's more of a pins-and-needles, limb going to sleep feeling, though it hits all my toes and sometimes a little further into my foot (never really past the ball though). This happened with my old flat pedals and several different pairs of shoes. I recently switched to clipless pedals and shoes and hoped it would stop with the stiffer sole and dedicated contact to the pedal, but no dice. My cycling shoes are quite comfortable and there is no pain associated with this, just the annoying numbness. Right now the only way I can fix it is to coast for a while so I can unclip and dangle/shake my foot around to get some feeling back into it. Unclipping and temporarily pedaling with my heel helps a little, but not much. Anybody else have this problem or know how to alleviate it? Or am I just stuck with it due to some quirk in my anatomy? <Q> There is probably a combination of things that can help. <S> In my experience, that helps a lot with circulation in my feet. <S> Obviously, you'll want to make sure your shoes are not laced or velcro-ed too tight. <S> I will often stand in the pedals and do calf stretches by flexing my ankles up and down (still clipped in) to help with foot circulation. <A> I have had similar issues with numb feeling in my toes. <S> Have tried my cleats in every possible position but it did not help. <S> My local bicycle shop owner suggested some arch supports, he thought it had to do do with me having quite an high arch that pressing it down that much interrupted the blood flow. <S> Since I have arch supports <S> I have not had any numb toes while cycling. <S> Hope this helps you. <A> One common solution is to move feet slightly forward in relation to where you usually put it when pedaling. <S> So in short, try moving your cleat further back from its normal position (the ball of the foot) to relieve the nerves at the base of the toes. <S> A suggestion by Lon Haldeman (Race Across America competitor) is to move them back so much you actually have to drill new holes into your shoes to fit them: https://docs.google.com/a/lopsae.com/file/d/0B3sCYFto8z6rbDRRbHB0cmNfLVU/edit
|
Periodically getting your weight off can help as can making sure your pedaling stroke includes ankle flexion. This is easily achieved with cleats since their position dictates exactly that.
|
Forearm pain during and after cycling I've been riding for a couple weeks after years of not sitting on bike in order to strengthen my health. I've been commuting to my work and school (12km/7.45 miles from my home) about three days a week and then resting/waiting (because of seasonal rains in my area). About three weeks ago I've started to feel ache in my right forearm in area highlighted in picture and it continues to ache for a couple more days when I lift something heavy or twist my hand or sometimes even without cause. After about ten days it has gone, but when I got on bike three days ago again, it has started again. Sometimes I also feel numbness or cramps in fingers in my right hand, but when I take off my hand of bike and stretch my fingers for a couple of seconds, it will go away. Any suggestions what could be the cause of the forearm pain? I will see my local orthopedist in a week, but I don't trust him much as he is pretty lazy to even properly diagnose something. The only thing that has crossed my mind is that my handlebar is too low for me. <Q> There are multiple possible causes for this kind of pain. <S> Of course, you should see a medical person in case something more serious is going on than our amateur diagnosis suggests. <S> In general, this is a kind of overuse injury. <S> This can have different causes (and each would have slightly different symptoms). <S> Part of the reason is that you've taken a break and those muscles are just not as strong as they used to be. <S> Common causes are <S> The most common cause is your seat too high relative to the handlebars, leading you to put more weight on your forearms. <S> This would be more common for mountain bikes and flat-bars, and seems more likely given the posted diagram. <S> Another cause to gripping too tightly. <S> This can also be due to repeated hard braking. <S> You could be overstretching the tendons / muscles, by riding with your wrists low so that your hands are higher than your wrists, or with your wrists bent to the side so that each wrist is bent inwards or outwards. <S> This is more likely on a road bike if you ride with your hands "on the corners" a lot. <S> Or perhaps if the handlebars are too narrow. <S> You would probably know if your enthusiastic gear changes were causing it. <S> EDIT <S> Everything is interconnected, so changing one thing without full understanding can have unintended consequences. <S> If you make changes yourself then be vigilant for other issues. <S> Taking the bike to your LBS to get them to check your position is recommended. <A> I get something similar from high-seat / low handlebars. <S> It seems to be pressure and circulation / nerve related. <S> The easy fix was to get some of these large surface area bike grips http://www.amazon.com/Ergon-Biokork-Bicycle-Handlebar-Grip/dp/B004P8FN28 <S> Also- if you're wearing a backpack, this will add a bunch of extra force on your hands. <S> So keep the bag light. <A> Two other possibilities that have created wrist pain for me: 1) Large, hard handlebar grips. <S> You wouldn't think it make a difference, but I used to get a pain in the wrist every time I rode my wife's bike, until I replaced her grips. <S> 2) Too much acceleration. <S> When I accelerate, I use my arms and chest to wobble the bike against my legs, it never used to be a problem <S> but when I started doing it again after a long pause, I could really feel my wrists and forearms being stressed. <S> If you find that one of these is the problem there are simple solutions.1) <S> Replace with soft grips2) <S> Start shifting gears more.
|
Often the solution to this kind of problem is suggested by the diagnosis but requires some experimentation because the the result of a change can be hard to predict. You could be gripping the handlebars too tightly, or trying to do too many jumps, etc. Even stranger, it can be caused by pushing too hard on indexed gear levers.
|
Cyclocross Bike On the Road I ride road and MTB, but want to add a cyclocross bike and do long distance, all day adventures which would include 50/50 (road/off-road). I am not interested in racing, but do want to participate in events, etc. My question: What are the best tires to run on a CX bike under these circumstances? Thanks. <Q> I've ridden many different tires on my cyclocross bike, and I've found that a 32 mm is the comfortable on the road. <S> The most fun I've had though is on 40mm Clements, especially if there's any off road involved, if you can fit them on your cross bike. <S> https://www.biketiresdirect.com/product/clement-xplor-mso-60-tpi-adventure-tire <A> You have to compromise. <S> On road you want smooth and off road you want tread. <S> On road touring or road tires. <S> Off road you want some tread. <S> Anywhere from a 700 X 34 - 700 X 38.A small block will give you some traction but still do OK on the road. <S> As mentioned by hillsons - the Clements. <S> For sure you don't want wide spaces knobs as they are poor on the road. <S> A CX tire is just not going to last as long as a touring tire. <S> A CX tire is not going to be as puncture resistant. <S> For me I take a touring tire for road performance and durability. <S> A knob has poor wet road performance and if weather turns bad I just want to get home. <S> If it was serious off road I would take my mountain bike. <S> On gravel and hard pack I just don't ride aggressive. <S> If you are riding 20 miles to get to some cool trails then go with a CX tire. <S> At 50/50 you have to decide which 50 is more important. <S> Look for a CX bike that will take larger tires. <S> You still have option to run smaller tires. <S> Also look at gravel bikes. <S> And don't rule out a light touring bike <S> - do you want a rack for your all day adventure. <A> I've found that slick tires can lead to unpleasant surprises on loose surfaces, such as a thin layer of gravel on top of hardpack. <S> I used to have Clement Crusader PDX tires on my cyclocross bike. <S> I liked them because they were 37mm wide, even though they are labelled 33mm. <S> The extra width doesn't slow you down, but it makes the ride more comfortable, plus it works better on loose gravel. <S> These days I ride that bike mostly on the road, so I've switched to 35mm <S> Schwalbe Kojak tires for now. <S> If I'm riding entirely on asphalt, then there's no point in having knobby tires. <A> Clement X'PLOR <S> USH 35mm <S> Clement X'PLOR MSO <S> 40mm Surly Knard <S> 41mm <S> I own <S> Clement X'PLOR <S> 41mm tires. <S> USH tires are faster than Knards, they are pretty good on gravel but not as good as Knards. <S> On the other hand, Knards are really good on the gravel, even on MTB sigletracks. <S> However, Knards have bigger rolling resistance on the pavement so expect it's slower than USH.If <S> you think you'll ride on the pavement more, choose Clement X'PLOR USH. <S> I haven't tried MSO yet but people generally say that MSO has similar performance to Knards on the gravel but faster on the pavement. <A> The best tires I've ever used for linking up dirt and road in the same ride are Avocet Cross II's. <S> They had a "negative" tread. <S> (i.e. grooves in a mostly slick tire.) <S> Unfortunately, they are no longer made. <S> There are lot's of choices for this kind of tire for "gravel grinder" riding, if you ever run across anything that looks like the Avocet, buy it. <S> Panaracer Pasala's are usually cheap and generally work well. <S> For the most part you need much less tread than you would think at first, but you do need some tread. <S> 32mm or larger tires really help. <S> The only place tread is really required is when you have loose material over a harder surface. <S> If you have only hard packed dirt, (very common in the SF Bay Area), you can get away with a traditional road slick, although a fatter tire will provide a more comfortable ride on the dirt sections. <S> In general, you want a tire that has a solid a central ridge as possible and some tread towards the shoulder of the tire. <S> A negative design works well because you can "tune" the amount of tread by changing the inflation pressure of the tires. <S> I would avoid knobby cross tires that look like skinny MTB tires. <S> They add a lot of rolling resistance on the road and can be squirrelly on hard surfaces. <S> They are meant forriding in mud. <A> Schwalbe CX Comp or Smart Sam in ~32 <S> mm width. <S> Low pressure is most important on gravel etc. <S> the profile is only useful in mud etc. <S> If it’s really light off-road <S> you could even try a Continental 4 Season in 28mm.
|
So I'd recommend a cyclocross tire with a decent tread pattern (a bit like a mtn bike tire). For most dirt road surfaces, the size of the tire is more important than the tread. Anywhere from a 700 X 32 - 700 X 38.You get low rolling resistance and good traction on the road. Otherwise, choose Knards or Clement X'PLOR MSO. Durability is a big factor for me. USH 35mm tires and Surly Knard
|
Can I use a road bike for commuting 11 miles each way without SPANDEX I am thinking of getting (investing in) a road bike for my 11 mile commute (total 22 miles each day). I want to continue wearing normal work clothes - meaning hiking pants and a T-Shirt. I plan on using the Spiderflex seat (taken from my Mountain Bike) on a road bike. The Spiderflex eliminates any seat pain, and there is no chafing, ever.Can this be done? Does anyone do something similar? <Q> Yes, absolutely. <S> Clothing is mostly an issue of personal preference. <S> Performance fabrics and things like spandex don't make that much difference for short stretches, and their advantages become more pronounced and valuable the longer you ride. <S> 11 miles is somewhat of an intermediate distance; in regular clothes you'd be totally fine, assuming that the weather and the road conditions won't make your work clothes sweaty or dirty by the time you get there. <S> For commuting to work, I'd make the decision more on the basis of road conditions and comfort. <A> However, bike shorts are crafted from fabric made to resist pilling from the friction created when your rear rubs against the bike seat. <S> With your seat this might be reduced compared to seats made of rougher material, but even if you aren't feeling any chafing, the friction might still have a negative impact on the fabric of your pants, especially as you rack up the miles. <S> I've biked similar distances in pants and shorts made for hiking, and the synthetic ones pill a lot around the crotch area after riding a decent amount. <S> None of my spandex bike shorts or baggy mountain biking shorts have shown this wear. <S> If keeping your hiking pants looking nice for a casual office environment is a concern, I would recommend either biking to work in a separate pair of pants, or investing in a single pair of baggy mountain bike shorts. <S> These tend to dry fairly quickly (probably like your hiking pants) due to their synthetic composition. <A> Answer <S> Yes - totally possible in normal clothes. <S> Its the muscles to do the work, and the fit of the clothes to avoid friction, that count. <S> Normal clothing is all about comfort, and lycra/spandex/etc are more about cooling and aerodynamics. <S> Remember there are such people as nudist cyclists. <S> Shoes are somewhat different - you really should be wearing comfortable shoes not dress shoes.
|
As long as you're not chafing, normal clothes suitable for the conditions are fine. I would try riding 11 miles in these pants once, and as long as you haven't experienced any discomfort from riding this distance without spandex shorts that contain a chamois pad, you're unlikely to experience much discomfort as you ride more often.
|
Shifter cable running beneath the bottom bracket without a sheath I am trying to solve the neverending issue of my derailleur shifting on its own by replacing the shifter's cable and its sheath to see if it not sliding properly could be the cause of the issue. Doing so I realized that both derailleurs' cables run beneath the bottom bracket in two rails, without any sheath wrapping them. In this picture, I removed the front cable (that was running in the left rail) while the rear derailleur cable is in place on the right rail. (yes I know the frame is very dirt, I just noticed. Never checked this thoughtfully down there). I am wondering if this could be the issue of the friction, before installing the new stuff back. I noticed that that piece where the cables run into, can be replaced (though I don't know what to search for. By the way has that component a name?).I am wondering this because the bicycle is quite old (it's a 2001 bike) and perhaps that has been superseded, and, most importantly, because I feel like I cannot lubricate those rails where a lot of friction must happen , because, being those so exposed, the grease down there would catch any kind of dirt and mud and probably make things worse. Or maybe it's just fine as it is, with no lubrication at all, and I am totally seeking for the issue in the wrong spot. Any clarifications about that piece of gear would be immensely appreciated. Thank you very much. <Q> Ghost shifting is generally caused by the frame flexing, not by friction in the cables. <S> Other causes can be a poorly fitting or too short cable housing. <S> Something is causing the length of the cable between the stops to change. <S> When thisis the cause the problem tends to be very intermittent and only occurs when standingon the pedals to climb. <S> However, as Daniel R Hicks suggests, check the frame carefully for cracks. <S> An aluminum alloy frame of that age that has seen a lot of miles is at the end of it's usable life. <S> If you can't find any cracks, examine the cable housing runs carefully. <S> The cable housing ends should not move at all in the stops when shifting or turning the handlebars. <S> The part you are looking at is called a Bottom Bracket Cable Guide , but your's looksjust fine. <S> They rarely wear out, shift cables aren't under much tension, so a plastic slider is plenty slippery enough. <S> On an old enough bike, they are made of metal. <A> A couple of things could be the reason of your derailleur shifting on its own. <S> I assume that both the derailleurs and the shifters are in good working order, that you washed and lubricated them and correct adjust them with the respective screws. <S> Please refer to Park Tools repair help guide to correctly set all these adjustments. <S> You can find it here and please bookmark it, because their site is nothing short of amazing. <S> And now that we are talking about this, also check for the rear derailleur hanger alignment, as you can see here . <S> Now that we know this is not a problem, the main reason of poor shifting is your cables being dirty and/or simply old. <S> Replace everything, inner and outer cables. <S> Buy the cheapest ones is usually good enough, a good tip is to put teflon-based oil (cheapest you can find, it's a good buy because you will use it for the derailleurs, chain, etc) inside the outer tube before putting the inner tube in. <S> This will ensure good operation for a long time. <S> About you bike's cable routing, you can find a new plastic piece for your frame here (make sure this is the correct model). <S> I wouldn't bother if yours look good, just clean it. <S> The type of routing on your bike is definitely not the best (as you can see lots of debris accumulate there), but that's ok. <S> There is a neat thing you can do: pass the cable for the front derailleur through the standard places (down the inner tube), but for the rear derailleur use a big outer tube that goes all the way from the shifter to the derailleur (check what works best with your bike frame, if down the top tube/seatstays or through the down tube/chainstays, and choose whichever route because since we are using a outer tube debris are not a problem anymore). <S> This will ensure that cable stays clean and protected and your shifting should be good for a longer time. <S> You can buy cable guides like <S> these (there are more types, just google for it) <S> but I would just use zip ties and do something like this . <S> Be patience and good luck! :) <A> Before you buy anything,make sure the shifter is adjusted corectly. <S> Put the bike on a stand or whatever it takes to allow the pedals and the rear wheel to move freely. <S> The adjustment should be made from the second highest gear (the second smallest Which is the second from the outside). <S> Tighten the adjuster until the chain makes noise trying to shift into the third gear,then back it off until the noise stops. <S> If that doesn't solve the problem,see if the derailleur or the hanger is bent. <S> There could be many reasons for ghost shifting but if the shifters seem to work smoothly then personally I would not suspect the cables or worry about friction on the cable guide. <S> Hope that helps.
|
Cleaning the cable run and using a teflon coated shift cable won't hurt and might alleviate the problem if it's a combo of bottom bracket flex and sticky guide. Check the derailleur hanger to make sure it's not loose.
|
Are out of date energy gels bad for you? I have some energy gel sachets that are a few months out of date. Do they contain anything that might be dangerous after their best-before date? <Q> I don't think this is problematic. <S> So if none of the following conditions are fulfilled, I wouldn't mind using such a gel that is some months over their "best before" date: <S> The sachet hull is intact, i.e. there are no signs that unwanted air could have gotten in. <S> Look for unwanted openings like deep scratches in the foil, rips, or signs that the package has been havily compressed or worked. <S> The gels have not been stored in extreme conditions. <S> As long as they were at moderate temperature and not exposed to sunlight most of the time everything should be fine. <S> Also having carried them in your backpack for the weekly ride in summer should not be a problem. <S> I would be somewhat concerned if you had had them with you on a two or three weeks tour in hot climate. <S> If you are unsure or have to rely on your food on a longer ride do the following: Try one of them at home to see if it's OK and take other food with you on tour as well, so that you can leave the gels alone in case <S> you are not sure about them. <A> I would probably eat them if they look and taste ok. <S> Also check if the package looks ok (and is not swallow, for example). <S> It is up to you though. <S> Ask yourself: would you eat an yogurt or cookies in the same situation? <S> It is not because these are made of sugar that they hold better or not. <S> Some products do, some products don't, and the manufacturer of your gels knows your product better than you, and set an expiration date for a reason. <S> This is true for all edible products, energy gels are no different. <A> I've checked this question before I took my few months out of date GU gel for a run. <S> Your answers gave me lots of confidence to chance it on a long run with no washrooms in sight. <S> I'm happy to report that it tasted just like normal and nothing bad happened to me at all. <S> Now I'm looking forward to finishing the remaining few I have left. <S> Money saved. <S> As always, smell it first before you put it in your mouth. <A> Hello All: <S> I used a GU this weekend <S> that was 5 years out of date. <S> It tasted and smelled ok and the packaging was intact. <S> 28 hours later, nothing has fallen off my body, and I just swam 2200m! <S> While it should always be "user beware" for out-of-date packaged foods, that is one person's experience.
|
So basically you should be safe and even if you have a spoiled one you should notice that as soon as you taste it – I don't think they will spoil in a way that you cannot notice but will get sick from it. I wouldn't risk it on a race day but for training it should be fine. Those gels consist mainly of sugar which is a good preserving agent and are sealed air-tight which means they shoudn't get easily contaminated.
|
cold setting 3-speed road frame to 7 8 speed cassette So my old road bike has a 3-speed freewheel, dropout spacing is about 114 mm. I'd like to give it an upgrade and put a 7 or 8 speed cassette (maybe stick with a freewheel if 6-7 speed, I just want more range and less hustle) Spacing of a modern cassette-type road hub is 130 mm. As the Sheldon Brown bible says cold setting is achievable but it doesn't say how many speeds you can go up. Many people go from 5 speed to 7 speed, or from 7 speed to 10 speed, but I couldn't find anyone on the internet who tries to go from 3 speed to 7 speed. My worry is that it is too much difference I have to spread apart and that it may damage the frame. My weight is on the heavy side and I don't want to end up with my teeth on the road :-P To sum up, will it be safe to resize from 114 mm to 130? <Q> Cold setting a 114mm to 130mm is significant. <S> Usually the rule of thumb for cold setting is you can go up one step, such as from a 126mm to 130mm or 120mm to 126mm. <S> A three speed freewheel bicycle is extremely rare <S> and I'd personally leave it alone, it's just too valuable to risk destroying the frame. <A> Personally I would not stretch it that far. <S> Aside from spacing you should check if your frame has derailleur hanger, and cable stops. <S> Lastly you would have to ensure proper chain line after the stretch, possibly requiring BB and/or crank set change. <A> One upgrade you could make without attempting to cold set the frame to far would be to use a kit like fyxation sells which works on a 120mm (track spaced) frame and works with bar end shifters. <S> It's a much smaller width, so it would possibly work better than cold setting to 130. <S> http://www.fyxation.com/products/six-fyx-conversion-kit
|
I bet you could mount the bar end shifter on some Gevenalle levers if you prefer shifting from the hoods or use some paul mtb thumbie adapters to mount them on flat bars if that's preferred.
|
Attaching kid trailer to rear triangle Have a cube aim sl MTB and a kid trailer that's designed to attach to the rear bottom side of the rear triangle with a clamp. The problem is that the clamp is not big enough to safely attach to the bottom side of the triangle since it's quite square and big, as can be seen in the picture below: Question: is it ok for the bike and trailer to attach the clamp to the seat stay since that tube is a lot slimmer. <Q> I had a similar trailer clamp <S> it was terrible, I ended up buying a hitch that connects to the axle and removed the clamp. <S> I attached a length of aluminum tubing with some holes drilled in it in place of the clamp. <S> I slip the tube over the axle hitch and then use a hitch pin to keep it all in place. <S> Its on my other bike currently but the hitch looks like this. <S> I find this a way better system than the clamp. <A> If you can find some other tube on the bike frame that fits the clamp better, that should be fine. <S> Obviously if you attach the clamp too high, the trailer will be tilted at an angle which would be uncomfortable for your kid. <S> I used to have a trailer with a similar attachment. <S> I noticed that the clamp can have a tendency to come loose from vibration, if it's not super tight. <S> The idea is that you notice that something has happened to the trailer and you can pull over and fix it. <S> It's not designed to keep riding without the clamp, except for 20-30 feet until you can stop. <A> I have one of these - it backed loose and fell off after 50 km. <S> The only thing saving it was the safety strap. <S> Clamp was tightened enough to chip most of the paint off the chainstay. <S> And that was with an empty trailer! <S> Imagine <S> what would have happened had kids been in it? <S> Now I check the clamp every 10 km, and I won't tow kids in it. <S> I intend on replacing the screw clamp with with a ball clamp and fitting a 1/2" towball to each of my bikes.
|
If the trailer doesn't already have it, I would rig up some kind of safety backup system, where a string/rope/bungee will hold the trailer arm if the clamp suddenly lets go.
|
Can I use "normal" shoes/trainers with clipless pedals? Is it possible to use regular trainers/shoes (i.e., withou cleats) with clipless pedals? A friend of mine mentioned he does this all the time. However, I cannot imagine how this would work. Surely the area of grip would be far too small to get any kind of purchase on the pedals. We both have Shimano PD-R540 SPD pedals. <Q> Also, there's a risk of your foot slipping off, particularly in the wet. <S> There are various options to temporarily convert clip pedals into ordinary flat ones. <S> Fly pedals BBB BPD FeetRest pedal adaptors (SPD only) <A> UPDATE: <S> I use Fly Pedals now when I want to convert my clipless pedals into regular pedals. <S> They are made of machined aluminum, light weight, and lock together so you can put them in your pocket. <S> They cost $50 plus cleats. <S> enter link description here <S> This company (started on Kickstarter) <S> makes flat platforms with straps on top and cleats on the bottom. <S> They convert clipless pedals into toe clips. <S> A pair runs $55 without the actual cleats. <A> There is nothing to stop you from getting on your bike in regular trainers instead of shoes with cleats. <S> you won't damage your pedals in any way as long as you don't have a rock lodged in the sole of your shoe. <S> The problem, as far as I can see it, is that it is just not very comfortable due to the small surface area and flexible sole of the shoe. <S> Your feet will feel the pressure localized into a very small area. <S> The other issue is grip. <S> There isn't a lot of traction since the body of the pedal wasn't designed with that in mind. <S> I do my own mechanics out if my garage and will occasionally hop on the bike <S> I'm working on to make sure my repair or adjustment is working properly. <S> I have bikes with Ritchey Logic, Speedplay frogs, SpeedPlay Zeros, Shimano SPD and non-clipless pedals. <S> I don't go and put on the proper shoes just to ride down the street and back while I test an adjustment. <S> So, yes, you can ride without shoes with cleats but really only in a very limited way. <A> Yes you can. <S> No it's not going to be comfortable. <S> You're more likely to slip off the pedals. <S> One alternative is to get double sided pedals where one side of the pedal has an SPD mount and the other side is a flat pedal. <S> I've been running Shimano M324 pedals on my commuter <S> so I can hop on with casual shoes or use my cycling shoes for more power on longer rides. <S> It's the worst of both worlds, so you'll find yourself trying to flip the pedal from time to time, but it's a doable option that gives you flexibility without having to swap pedals all the time. <S> Unfortunately, I don't know of any other type of shoe / cleat combination that works with dual sided pedals. <S> It seems that only shimano mountain SPD seems to offer this option. <S> If you're already sold on road pedals, then it's probably not going to work like this. <A> I have used normal office shoes on look road pedals (albeit shoes with relatively thick soles) <S> This works fine for to/from work or lunchtime errands. <S> However I found that pedalling on the "underside" of the pedal was more comfortable in some thin-soled shoes. <S> Not ideal but workable. <S> Another option, try clipping a plastic cleat in the pedal, an older and worn-out one would be perfect. <S> Plus you can remove it when you want to ride with proper shoes. <S> I have look clipless on my road bike, but I put platforms back on my MTB for trips around town, mostly because our roads are still terrible, and the MTB has better brakes and more load-carrying capacity. <S> Cleats may not be best for you. <A> Don’t wear sneakers over clip-less pedals! <S> Didn’t feel bad then <S> but when I woke up with ball area of the foot swollen with terrible pain. <S> Icing as I text. <S> I knew better too.
|
You might just want to invest in a set of flat pedals and swap your pedals when you want to ride without clipless shoes. Yes, you can use them with normal shoes, but as you predict, it isn't very comfortable, especially if your shoes have thin, flexible soles.
|
Tips for adjusting Shimano M355 hydraulic brakes I have upgraded from cheap old front cable disks brakes and rear v-brakes to Shimano hydraulic M355's front and rear. I always adjusted my old brakes for a very tight fit (to reduce dead space between pads/rotor) thus shortening my lever throw. As a sidenote, I know the M355's are the lower end of the hydraulic spectrum but i would have expected them to be better than my old lower end cable brakes. Also, I have bled both of these brakes twice in succession so air cannot be an issue Q1.With these new hydraulics there is a large space between the pads and rotor. The pads do auto-adjust correctly but not enough. Are there any tricks to modify this? (I have tried over-filling the system and it works briefly until the pads wear down a bit. However, i am unsure if overfilling could damage the bladder/diaphram in the lever) Q2.I have noticed that both the front and rear levers feel different when applying braking pressure. The rear feels nice and soft, yet firm and feels the same all the way through the stroke. It also provides good power. However, on the front, when the pads contact the rotor, you can really feel the lever go from soft to hard immediately. The front does not provide as much power as it should.Does this indicate something is wrong? If so, what? Sorry for the long paragraghs, just trying to give you all a clear picture. Thanks in advance for any help <Q> First, I think you made a good decision. <S> Hydraulic disc brakes are the way to go, and the M355 are really nice for the price. <S> Also, I assume brake pads/discs are not contaminated and caliper is straight in relation to the disc. <S> These are indeed the cheapest brakes, and therefore there is not much place for adjustments. <S> If without touching the lever the pads don't touch the disk, and when you apply they do, than I would say they are ok. <S> Maybe you would like them to do have a tighter feel, but with this model there isn't much you can do apart from lever distance to handlebar <S> (play with this a little to feel confortable). <S> I don't think overbleeding helps. <S> It shouldn't cause any harm, but the brakes were designed to work in a specific way, so it might affect behavior under heat, or might be causing the "instant brake" feel you are talking about, or might cause rubbing with new pads. <S> (there is so much tube going to the rear, right?). <S> And also, as the rider you are more sensible to brake forces in the front, and they affect more the dynamics of the bike. <S> One thing I would recommend you to do is to bleed according to manufacturer's instructions and try to adapt. <S> The change from pads or mechanical disc is huge in terms of the relation between lever force - braking force, and it is normal that as a rider you need some time to feel comfortable as you change muscle memory. <S> For example, on my road bike I always pull the lever/pads with as much strength as I can to do an emergency brake, whereas in my mountain bike with hydraulics I have to re-teach myself that I must always modulate brake lever even in an emergency brake. <S> The dynamics are very different. <S> Of course there might be something wrong with them, but from your description I doubt it. <S> If you can't take it out of your mind though, go to a shop, pretend you want to buy a bike with the same brakes as you have and ask for a small test-drive :) <A> The space is normal and overfilling should not alter this (over bleeding can be used to improve lever feel though see this blog article from Epic bleed solutions ). <S> As you say the pistons will adjust automatically. <S> That said if the calliper was not centred correctly around the disc then you can sometimes have a situation where the gap is larger on one side than the other. <S> In this situation the pad on one side will contact the disc first and push it towards the second pad. <S> Both brakes should feel the same (or very similar). <S> Its is normal for the rear brake to feel slightly softer due to the longer hose run (deforming of the hose as mention by super ). <S> As a previous answer states I would expect that both brakes should feel like the front currently does. <S> The quick change from soft to hard suggests both pads hitting the disc at the same time. <S> I may be worth removing the rear pads, pushing the pistons back and having another go at centring the calliper. <S> You can normally use the join between the 2 callipers halves as a guide (some brakes such as Hope's offerings have a centring line machined/marked on the calliper to aid this). <S> If the front brake is not producing the power you are expecting then it may have become contaminated. <S> Do you have an brake cleaner or Isopropyl alcohol? <S> You could try cleaning the disc with this and fit new pads (or the rear pads) to the front calliper. <S> If this gives more power then the previous pads are contaminated and need to be binned (I have heard of many methods for reviving contaminate pads but none work in my experience). <S> Finally in response to a comment on one of the answers you can get feedback via hydraulic systems. <S> One example of this is in your car when the ABS kicks in, you can feel the pulsing through your foot. <S> You can have a similar feeling from cycle brakes where the rotor is warped/bent. <A> Regarding Q2 -- I think both brakes should feel like your front brake -- when the pads contact the rotor, the lever feel should change instantly. <S> If this is not the case for the rear brake, I assume it is due to <S> (tiny) air bubbles somewhere in the rear brake system. <S> It is strange that in spite of this, you observe that the front provides less braking power than the rear. <S> Perhaps the front brake pads or disk are contaminated with brake fluid or some other liquid ?
|
Another thing to notice is that it is normal, even in good brakes, that the rear and front feels slightly different, because of expansion on the tube under braking The gap left should be equivalent to the displacement of both pistons by the master cylinder (lever).
|
Why so few mountain bikers with spandex? I've never had clothing that was specialized for cycling, so I'm kinda n00b in that area. I am confused about the use of spandex. It's very common among roadies, for obvious reasons. It's more comfortable, has less friction on the seat, and is more aerodynamic. Why doesn't it make sense for mountain bikers? You do see plenty of XC riders with spandex, but not in "120-160mm travel" areas like trail/enduro. Those guys seem to use basic shorts of one type or another, that catch air and might catch on branches. Why isn't spandex just as common in the mtb circles? Is it a cultural thing? <Q> As already said, aerodynamics are less important to MTB's, but otherwise its largely convention and fashion that dictate what people wear. <S> A vast majority of MTB'r are not wearing basic shorts - they are usually wearing shorts made for riding, including padding just like Lycra road shorts, flat seams and materials designed to withstand the rigour of riding. <S> For me personally, I wear baggies <S> MTBing <S> I will wear lycra if doing long distances, or I know I won't be more than 10 feet from the bike for the whole time I am out, but feel more comfortable wearing shorts. <A> Those guys seem to use basic shorts of one type or another <S> Most (at least those who pedal more than 5 miles per ride and have been riding for more than 1 year) use some form of spandex with padding below the shorts. <S> that catch air Doesn't matter. <S> and might catch on branches. <S> Doesn't happen. <S> The hands and elbows in modern MTBs are very very wide compared to the shorts and at the same level/height with the shorts. <S> If something is to catch, it's the hands/handlebars/elbows/shoulders first. <S> Never the shorts. <S> Is it a cultural thing? <S> Wearing spandex only, yes, it's a cultural thing. <A> I like to have shorts that cover my knees when mountain biking <S> but I still wear spandex sometimes. <S> Some of those shorts have cushion built in too and since we aren't generally trying to go 100+ miles, there is not a huge need for aerodynamics.
|
Many MTB shorts consist of removable lycra under shorts with the baggy outer designed for cycling. because we often spend time "in public" - around cafes or pubs after the ride, socialising and I feel like a fashion mistake (and I am not fashion concious) walking into a cafe in lycra.
|
Why should you not just buy the chain with more links? I have the choice of buying a 114 or a 116 link chain for the same price. Why would I not buy the longer one and shorten it? In my case my bike previously had 108 links, and assuming that was correct, 114 should be sufficient, but given it may need shortened, is it not worth buying the longer chain just in case? <Q> If your old chain was sized appropriately for your drivetrain, and you're not changing anything, then you're going to shorten the new chain to the length of the old chain (via counting links, or lying the chains on the ground and pinching them together). <S> Then, you throw the remaining links into your tool box in case of needing them as spares for a repair in the future. <S> Eventually, you have enough spare links in your tool box and you start throwing the spare links away when you get a new chain (or better yet, as Kibbee suggests, donate them to a bike co-op/shop). <A> With 8 extra links you can make your own chain whip with a nice piece of wood next time you need to swap your cassette. <S> I actually did this recently. <S> Worker reasonably well. <A> I would think that both these are from different manufacturers, or maybe slightly different product lines (DuraAce vs. Ultegra). <S> I can't think of why a manufacturer would bother shipping 2 identical chains with one only having 2 links more than the other. <S> Choose one based on some other criteria such as which brand you trust more, or which is actually supposed to be better. <A> I would go for the 116 link chain just so that you have a little extra spare in case something goes wrong.
|
So, it doesn't matter which one you buy in the long run -- the chain just has to be long enough to begin with (unless its a bike which needs a longer chain, like a tandem in which case you need to buy 2 chains and combine them).
|
Shimano 105 10 and 11 speed compatibility Currently I have on my bike the Shimano 105 system (2 years old) with 10 speed cassette. Currently I am buying a new wheelset (Fulcrum Racing zero) made for Shimano 11 cassette. I was told that I can use my 10 speed cassette but I was planing to upgrade to 11 speed cassette in the future. Is the Shimano 11 speed cassette that comes with the latest Shimano 105 compatible with older 105 systems? I apologize in advance if I don't make myself too clear. Thanks for any help <Q> Zinn also notes that 10 speed FD might not shift as nicely as 10 speed FD with the 11 speed shifters, so may as well throw one of those in. <S> So, in the drive train, essentially all you'd be wanting to keep is the crank if you want to go from Shimano 10 speed road to Shimano 11 speed road. <A> Well I'm using 5700 rear with 6800 cassette and shifters with success. <S> You have to adjust the stops and it works. <S> I also run a microshift cents 10 spd rear mech with 6800. <S> The geometry of the derailleurs is sufficient with stop adjustment. <A> I believe that the answer was easier than all <S> you got there.yes all is easy and compatible. <S> All you needed was a spacer (normally provided) to be placed before the cassette on the hub, to make up for the space remaining. <S> But I see that you have been using it successfully already!
|
If you want to go from Shimano 10 speed road to 11 speed road, you'll need a new cassette, new shifters, a new chain and a new rear derailleur , since the cable pull ratios have changed (again).
|
Pros and cons of single-sided forks (Cannondale Lefty)? Looks like they save some weight, but how do they have a better strength/weight ratio than a traditional two legged fork? With the single-legged fork the fork and axle must resist huge bending all the time, producing even more of a problem than with the 2-legged fork under uneven compression. So how is this fork constructed and what advantages and disadvantages does this bring? <Q> The single-legged fork must truly withstand heavier bending forces than conventional forks, simply due to physics and asymmetricity. <S> Pros <S> The top is attached like a dual crown downhill fork, which is much stiffer than a single-crown. <S> The wheel axle is one-piece with the bottom part, which is stiffer than a quick-release axle (which is not solid at all) and on same level as a 15 thru-axle or 20 thru-axle. <S> This design is used also on cars where the wheel doesn't have support from the other side. <S> The biggest difference is inside. <S> While normal forks have round tubes that slide on oil film, the Lefty uses needle bearings on a square profile (same as the front leg of Boeing airliners.) <S> : <S> Such solution works with almost same friction under heavy side-loads, whereas sliding tubes, when side-loaded (uneven compression of legs), do get friction losses (rolling resistance wins). <S> Having conventional fork with one leg wouldn't work, such a fork would get stuck. <S> Having bearing-fitted 2-legged fork is an overkill and unnecessary weight. <S> The heaviest Lefty is still lighter than lightest carbon 2-legged. <S> You can replace the tire without removing the wheel. <S> Cons <S> If you need to remove the front wheel, you need to remove the brake caliper also. <S> The axle works only with Cannondale hubs. <S> Pre-2013 models of Lefty are not sealed, having the bearings track just under a rubber sleeve. <S> This required almost constant maintenance. <S> Previous models, as some bikers on forums complained, had more linear action: they were easier to bottom than normal forks. <S> So now the newer ones should have more progressive compression. <S> (This is opinion based, but quite a lot of it online, there are no measurements.) <S> A Lefty is much harder to service than a normal fork. <S> You need a couple of special tools, and the assembly is complicated. <A> My experience with Lefty goes back to 2000 when I purchased my Cannondale Super V. One thing I've liked about it <S> how easy it is to 'turn off'. <S> There's a small dial at the top that disengages the suspension - good when transitioning onto solid road riding. <S> As mentioned above by another post, the center of balance is altered. <S> The implication of which is that it is more difficult to ride 'hands <S> free'. <S> Sometimes I ride hands free with it just to practice my balancing skills. <S> I seem to remember that the original intent was that lefty offered a longer(higher) range of motion and thus the bike was able to handle more adverse terrain. <S> I'm not sure if that's actually true, but it sounded good at the time. <S> If you do get one, you'll find it to be a conversation piece. <S> And one last thing, I've always considered the bike to be "much more of a bike than I am a man". <A> <A> Like everyone, the first time I saw this fork I find it obvious that it must be weaker than conventional forks... <S> Until I realized that conventional forks are not symmetrical at all. <S> One side is the spring (air or metal spring) and the other side is the damper. <S> This means the sides always works against each other. <S> The fork is teared a on its sides and it do not behave exactly the same whether you turn left or right. <S> The forces are not applied to the same side of the plunger and it does not slide evenly on both sides. <S> Having damper and spring on the same axle is a good point for the lefty. <S> Unfortunately we cannot do blind test on bikes, but it would surely give lefty more points. <A> Con: <A> Pro: There is no "fork," so mud and other hub-bub will not get stuck in the front as much. <A> I'd add:
|
But because of its different construction, the fork is actually stiffer than most 2-legged. Post-2013 models have a rubber-sealed leg with bearings further inside and with one plain bearing at the bottom which allows for service intervals as normal forks: Because there is only one side on the fork, it limits you to using disc brakes only, since there is no place to mount any type of rim brake solution. Pro:probably less width overall, good for extreme mountain/trail bikingCon:center of balance is shifted off center line of tire. Pro: You can run oversize and plus size tyres on a lefty. The front of bike will look unbalanced until you get used to it. Since it hasn't been widely adopted, I'd imagine that the benefits are not overwhelming.
|
Do 16g CO2 cartridges have a shelf life? I mainly use my road bike during the triathlon season and now that the season is coming back around again, I am finding some old, unused CO2 cartridges from last season (fall). I typically use 16 gram CO2 cartridges and they usually fill my bike to about 90 psi. Are these cartridges still safe to use after months of inactivity? I've tried researching the matter online but all I've read applies to airsoft, etc. and not necessarily the 16g bicycling cartridges I'm concerned about. But, from what I did read CO2 cartridges have a chance of leaking if not stored correcty and may indeed have a shelf life. <Q> They last pretty much forever provided they haven't been damaged (e.g. punctured or rusted or something), so go ahead and use them. <S> If they're significantly lighter, they've leaked and throw them out. <S> Else, go ahead and use them. <S> But a few years (say less than a decade) is pretty much nothing in terms of having issues with the cartridges leaking. <A> Yesterday I was out biking and got a flat. <S> My CO2 canisters are many years old, I’m going to guess about 5 to 10 years old. <S> When I went to fill up the flat absolutely no aire came out. <S> The canister was undamaged and any visible way. <S> In hindsight was quite light. <S> So <S> yeah after many years your CO2 canisters can apparently totally let you down. <S> I was calling for ride. <S> It makes sense. <S> PHI extinguishers for example do lose pressure over years and this is why they are inspected and expire. <S> Believe it or not air molecules can move through the metal wall <S> just happens at a very slow rate. <S> In fact that’s the principle by which your bike tire loses pressure overtime. <S> And easily seen in a birthday balloon On a short time scale <A> I inherited a Crossman pellet pistol from my father along with some cartridges .They were about 20 years old when I tried to use them. <S> They worked but only had power for a few shots. <S> Another 20 years later I tried again. <S> This time They did not have enough for even one shot. <S> SO..
|
They last a long time but Not Forever If you really want to check them, you can buy a few new ones and weigh them on a scale (and compare the weights of the old cartridges to the new ones).
|
Replacing rubber connection in a bicycle trailer coupling I salvaged an old bicycle trailer. I have one concern though. The bar that goes from the trailer to the bike, I believe it's called the tow hitch, ends with a small rubber coupling, to allow for movement in all directions. The rubber has gotten brittle, and I don't trust it. Is it possible to either buy a new one or in any other way fix this issue? <Q> I suggest undoing the bolts that hold the rubber piece in place. <S> Obtain an old car tire, and with heavy shears, cut a couple of pieces the same size and shape. <S> The idea is to put them back to back to make up the width. <S> You'll need to make holes on each end for the bolts. <S> A large drill could be used for this; I suggest a drill press, rather than a hand-held drill, for safety reasons (the drill bit may bind in the rubber). <S> You may need to have a few tries to get it all to work right. <S> Good luck :-) <A> Yes, you can replace it. <S> Although you might have to goto another brands system, and a little hacking. <S> Personally, every trailer I have I use the Burley Flex Connector system ( http://www.amazon.com/Burley-Design-Connector-Round-Black/dp/B001GSQXUG/ref=sr_1_1?ie=UTF8&qid=1438004399&sr=8-1&keywords=burley+flex+connector ). <S> In the Burley case, the hitch for your bike ( http://www.amazon.com/Burley-Design-Forged-Standard-Trailer/dp/B00VSOQN8K/ref=sr_1_3?ie=UTF8&qid=1438004399&sr=8-3&keywords=burley+flex+connector ). <S> Here is the similar piece for the Burley flex connector system, and how it works on my bike: <A> What is your basis for not trusting it? <S> That bolt has rust <S> do you not trust it? <S> Really how do you know that surface cracking is a structural integrity problem? <S> Stand on it and see if it breaks. <S> If it breaks try a tire and frame dealer. <A> My trailer has such a spring by design and it works just fine. <S> In my experience the forces on the coupling are not enormous. <S> The largest forces happen when you brake, but these are compression forces and shouldn't tear it apart. <S> The pulling forces are normally not that large. <S> I would also add a safety rope from the trailer to the bike. <S> If the coupling fails for whatever reason, then your trailer doesn't get out of control.
|
Fix it to the bolt on the right side of your photo, and tie the other end to the bike frame, with just enough slack so that it doesn't stretch when the trailer moves in all directions and doesn't get caught in the wheel. What ever you go with though you may have to get a few other parts for it to all work. You could use a steel spring like the ones in old bedframes or around trampolins; it should be possible to get one from the nearest scrapyard or recycling centre.
|
Finding the right length of chain lock for my road bike I am trying to buy a chain lock as I would be leaving my cycle in quite a busy area. I am not sure what length of chain lock I will need if I wanted to secure my bike using a chain that runs through both the wheels and the frame. The 90cm Kryptonite looks two small to run through two wheels, I am not sure if I need two 1m chain locks or if I could do with one 1.5m chain lock I looked at the pragmasis protector 16mm chain lock with padlock. Anyone have any advice specifically on what length of chain lock i will need or if it is better to get two short chain locks both for the front and the back wheels <Q> I faced the same dilemma a while back. <S> Getting a big chain implies carrying way too much weight around. <S> Even a small, good bike chain is pretty heavy and can easily be 1/3 the weight of your bike. <S> One wheel is less protected, but a substantial part is under a good lock and the weight is not too bad. <S> From these I actually prefer a small chain to a u-lock because it is easier to lock the bike to a tree for example, but if your city is bike friendly <S> a u-lock offers very good protection and is much more manageable. <S> When buying locks keep in mind price usually means security. <S> I recommend you check the independent tester of locks <S> Sold Secure . <S> They have a catalog with different locks they have rated. <A> Grab some string, and thread it through where you want to lock up the bike. <S> Then measure the string. <S> It won't be perfect, or even all that good, but good enough to know to the meter how much you'll need. <A> You would definitely be better off buying two shorter chains rather than one long chain. <S> Plus two chains gives you more locking options. <S> And while a 16mm Pragmasis Protector chain is an incredibly secure choice (if paired with an equally good padlock), it's completely impractical for mobile security. <S> For example, the 1m long Protector chain with a Squire SS65CS Stronghold Lock weighs 12.13 lb (5.5 kg). <S> That's the equivalent of nearly 15 cans of Coke! <S> I think a 10mm chain is about the limit of what is practically portable as an every day chain. <S> The Kryptonite New York Noose is a good choice because the noose design means less chain goes further. <S> You might be able to get away with the 30" (75 cm) version. <S> But you would still need another lock. <S> Maybe a U-lock would be better for a secondary lock? <S> Or have you thought about two U-locks? <S> Whatever you choose, I wouldn't recommend anything rated less than Sold Secure Silver. <S> I run a website where you can compare the lengths, weights and security ratings of some of the most popular chain locks . <S> And U-locks too. <S> So let me know if you need anymore information!
|
The best way to protect your bike and be able to carry the locks around is to have a chain or a U-Lock, and with these you can easily secure your frame and a wheel, and then use a small cable like this to secure the other wheel. With one long chain that goes through both wheels and the frame you'll be wasting a lot of chain just covering the distance between the wheels.
|
How much of a difference does giving blood make to recreational cycling? I intend to give blood at some point this week at my local community centre. How much of a difference is this going to make to the effort required to keep up my usual pace? Or will the difference be negligible? How long will any potential effects take to wear off? I know professional cyclists have in the past (of course this is completely eradicated nowadays...) increased their blood volume to give them an advantage over the rest of the peloton. Can I infer that a lower amount of blood will have the opposite effect? I commute ~16km most days and usually go out for a longer ride at the weekend so I'm fairly used to cycling intermediate distances. <Q> It can take that long to replace the red blood cells you've lost. <S> Since a blood donation is about 10% of your blood capacity, your aerobic capacity will be down by 10% <S> I wrote the rest of this before I saw your comment that you've given blood many times. <S> I'll leave it in the post for future readers. <S> Initially, the main issue is blood pressure. <S> Plenty of fluids are recommended as soon as you finish giving blood. <S> It only takes an hour or two to overcome this. <S> The conservative advice would be to avoid cycling for the next 24 hours. <S> Until you know how you react to giving blood this is what I recommend. <S> After giving blood a few times you could try riding gently and see what happens. <S> Edit: see also the link provided in the answer by @super . <A> Depends on exercise intensity. <S> A complete recovery of oxygen delivery can take as much as 3/4 weeks. <S> This means a professional athlete should be careful because he will loose performance, but us normal human beings can carry our normal daily lives. <S> You can read more complete answerers given by pro-triathletes and physicians, here . <S> You can also find scientific references to support their claims, if you really want to get deep into the subject (I didn't). <S> Curiously, they state there isn't much research in the topic. <S> I assume pro athletes just don't take the chances, and to normal people giving blood has a neglectable impact in our daily life. <S> If you helped another human being, who cares if you take more 5 seconds to do the 10 miles from your house to your local pub, right? :) <A> I used to cycle 8 miles each way on my way into central London, before I moved. <S> I also used to give blood before moving to a country where they prefer not to accept mad cow blood. <S> So there you go. <S> I found that on a good day I used to be able to cycle into work in about 40-45min. <S> I also found that the days immediately after a donation I would take 45-50minutes approximately to make the same trip. <S> Overall I found it definitely does make a huge impact on performance. <S> On the other hand that same performance change actually made very little difference to my commute. <S> TLDR <S> It's harder to cycle for about a month, or how long the vampires wait before bleeding you again. <S> It's also very manageable for commutes, but you will definitely not be hitting your pb. <A> I cycled up Box Hill today in 8.30 minutes after giving blood last Friday. <S> My fastest time this year was 6.40 and my slowest time when trying was 7.26 at the beginning of the year when I wasn't fit. <S> I would never have believed it would make that much difference <S> but I felt light head headed and if I had tried any harder <S> I think I might have fainted. <S> I just didn't seem to be able to get any air in <S> and I was breathing really hard for the effort. <S> I have low blood pressure anyway <S> so I wonder if that made any difference too. <S> As soon as I stopped cycling I felt fine and going along on the flat didn't feel too bad. <S> It wouldn't put me off giving blood but if I was planning to race <S> I think I would give it about 6 weeks. <S> The same thing happened a few years ago when I gave blood and did a 10km about 2 weeks later. <S> I thought maybe I was a bit under the weather <S> but I had the same feeling as today and was about 2 minutes slower than I would usually be. <A> Yes, it will affect you, but I doubt you'll notice the difference. <S> red blood cell count and your body can replace the fluid relatively quickly, so have a cup of tea and a chat before you leave <S> and you should be ok. <S> When I was giving regularly, they asked if you were going to be operating heavy machinery later that day. <S> If you tick that they'll ask you about it and give you better advice than someone anonymous on the internet...
|
Some people do feel fait afterwards, but I believe this is related to blood pressure rather than I would still avoid riding on roads in traffic. If you are riding near your aerobic limit you'll definitely discover that you've lost aerobic capacity during the next 12-24 hours. In a day or two you can return to your normal/moderate exercise. I also found that it would take approximately a month for me to recover my pb speed, which matched quite well worth when I would be due to donate again.
|
120 mm fork with a frame designed for 100 mm fork? I have a Cube Reaction Team 2011. It came with a Fox Alps 32 fork, 100 mm travel (26"). The fork is now ruined and I need a replacement (on a rather tight budget) and I found a good price for a Rockshox Reba RL Solo Air fork. It's 120 mm, but I think it can be adjusted to 100mm - I'm wondering though, would the extra 20 mm travel be a problem for my frame? My point is basically these two questions:: firstly, would it ride/handle worse , and secondly - would it put more stress on my frame , especially if the stress could be potentially fatal for it (it's a carbon frame and it's one that's difficult to get anymore, so I'd rather keep it intact). Also a side-question - is there any possibility that a 100mm, 26" fork would NOT fit my bike? I probably cannot install the fork myself and I'd rather not buy one and then find out at the bike shop that it cannot be installed on my frame. <Q> Before starting, your fork looks pretty nice. <S> Are you sure you can't send it to FOX and rebuild it? <S> Why do you say it is ruined? <S> About the fork size, please check the cube FAQ : <S> CAN I INSTALL FORKS WITH MORE TRAVEL <S> AS <S> PROVIDED IN THE STANDARD EQUIPMENT? <S> NO. <S> The installation of a fork with more travel will void the warranty. <S> The bike geometry will be changed in a negative way, which leads to a different handling of the bike and can damage the frame permanently. <S> If your bike is still under warranty, I don't think it is worth it. <S> If it isn't, it will for sure put more stress on the frame <S> but I don't think it will brake. <S> This depends a lot of your weight and ride style, and keep in mind <S> Cube says not to do it, so it is your entire responsibility. <S> I wouldn't do it. <S> Please check here . <S> Changing a suspension is simple, if you have the patience and the time to learn, and you just need one or two allen tools for most of it. <S> However, sometimes taking the bottom part of the headset from the old fork is a pain. <S> Search on youtube for fork replacement. <S> If you feel like it, I think you can try and if something goes wrong take it to a shop in pieces. <S> They will figure it out :) <S> and it's shorter size might not fit your frame or your favorite stem position. <S> IMPORTANT: Please see @mikes comment below. <A> +20mm you should be able to get away with. <S> Ride wise <S> you're <S> weight will be a tiny bit further back <S> so will make hopping/manuals a bit easier, your front could be more likely to wash out in corners though. <S> Really depends on the rest of your setup though and how you ride. <S> All in all i don't think it will make a massive difference. <A> I would say sell and buy a full bike (even second hand). <S> Components on bike are chosen to work together with the frame geometry. <S> Parts are way more expensive alone than as part of a bike. <S> You could change transmission, seat post, and maybe handle bar. <S> But don't mess with frame and suspension unless you know what you do. <S> But take care, on high quality bike those component are often customized to suit the geometry of the bike (especially rear dampers). <S> And for your information a Reba RL is far from real Reba. <S> You got the stifness and the look but the damper is not good at all, not reliable and hard to tune. <S> I got this fork, I liked it at fist because it was my first real mtb, but since then I always have problems with it.
|
As a guideline you can choose components that come with a superior version of your bike (same frame, better components). It is also not approved to install double bridge forks into CUBE bikes. Before buying, confirm with the seller the fork will fit the frame, specially if it is an used fork he might have shorten the part of it that goes into the headset I am pretty sure you can change your suspension between 80, 100 and 120mm of travel. Rock Shox has really good manuals so you might even be able to do it yourself, otherwise take it to your bike shop. I'd go for it.
|
What are the securing rings on the disc brake pads pin called? I've misplaced mine, and noticed the other caliper doesn't have the other one. How important are these? I mean, do pads fail or come loose at times, without these safety feature present? Is it possible to find a replacement? What other components have those? This is the back of a Deore M-535 caliper, where the pin is marked at the places it should have been secured, <Q> Usually it's called a Retaining-Ring , poodle-ring or a split-ring. <S> They will look something like this. <S> Special pliers are made for their removal and installation, but I usually just use needle-nose pliers. <S> I'm not familiar with that particular model of caliper, but I do think replacing the ring is probably important. <S> Your local bike shop may have spares specific to that part. <S> You can also try your local hardware store. <S> In the screws and bolts section the will usually have bins of split retaining rings because regardless of the application, when you remove one the "springiness" tends to make them fling off into the tall grass and get lost (at least whenever I do maintenance). <A> It seems to be known as an R-Clip or an R-pin: http://en.wikipedia.org/wiki/R-clip <S> The pin which actually holds the pads in is threaded and on all the Shimano brakes I've ever owned with this setup (3 bikes) I have never encountered a situation where the pin has come loose and the R-clip would have been required to stop the pin coming out. <S> Ideally the clip should be there should the worst happen, but personally I'd have no reservations riding without it. <A> That is a pin (which you have) and a clip (which you don't). <S> They are important because they ensure the brake pads stay in place. <S> Take it easy using your bike while you don't get it fixed.
|
In a pinch, you can tightly wrap and twist a piece of wire in the groove usually occupied by the ring to hold you until you get the right part. You can buy them online, here for example, but if your local shop is cool they should give you one from the lots of spares they have. They are part of the brakes's Pad Retention system.
|
Is it typical for the front and rear gear levers to be reversed? I recently purchased my first bicycle since I was a kid. The bike I bought has individual gear levers for shifting up and down for both the front and rear gears. I thought it was odd that these levers are set up in such a way that shifting the lever with my thumb shifts up on the front and down on the rear gears. Is this typical to all bikes with front and rear gear systems? Is there a way to change it? <Q> Originally, cables actuated the pulling of a mechanism, and release meant relaxing the tension, which mostly then let a spring return the mechanism to its lowest state. <S> This translated to pulling = lifting/pushing the system up, against the gears, so moving the chain from smaller, up onto bigger sets of cogs. <S> Dropping = <S> the easier task of letting the chain fall from big to smaller rings, which the internal spring could handle. <S> The issue you're asking about relates to the fact that "bigger" gears up front do increase your gear, but in the rear they decrease , or lower your gear. <S> The release of most thumb levers relaxes the cable, which drops the front to a lower gear, but drops the rear to a higher gear. <S> With a few unsuccessful exceptions that tried to use the spring to push the chain onto bigger sprockets, this is still the general pattern - EXCEPT <S> Now, I understand Electronic systems can be programmed entirely different, even mixing left and right signals front to back, an exceedingly confusing idea in my opinion. <S> Grip shifts are my preferred MTB choice, but again the tension/detension concept applies relative to which way you rotate the barrel. <A> This is normal for Shimano trigger shifters, and you'll get used to it quickly. <S> SRAM trigger shifters can be operated up and down with thumbs. <S> And there are grip shifts which turn a bit on the handlebars. <A> Mechanically, the shifting (front & rear) are the same. <S> Moving either shifter so that cable is pulled, causes the chain to move onto a larger sprocket (front chain-ring or rear cog) & releasing cable allows spring tension in the derailleur to move the chain to a smaller sprocket. <S> However, a larger chain-ring results in a larger gear ratio (higher gear) and a larger rear cog results in a smaller gear ratio (lower gear). <S> So, the same action on front or rear shifter has the opposite effect on gear ratio. <S> In practice, it only takes a little time before you begin shifting automatically; you will shift up and down on the front or rear without thinking about it.
|
Gear shifting has historical lineage, not always "logical" or intuitive by modern logic as observed by newcomers to the activity. When indexed shifting arrived about 30 years ago it just aligned the clicks to a particular gear; then, first in mountain bikes, then road, the integrated levers made one lever for up, the other for down. Learning to shift the traditional logic is easy enough to master in a couple weeks, so don't get worked up about something thousands have managed to cope with just fine. Aside from possibly trigger->gripshifts, you'd be doing a decent amount of drivetrain overhaul.
|
Fundamental principles of tire friction for off-road biking This is a two-part question. I've been watching various videos and getting various advice about mountain bike cornering. My impression is that all of the advice cannot be true, because the advice, taken together, seems self-contradictory. Also, some logic out there seems rather disconnected from the physics. A few years ago, I read this book on race car driving: "Going Faster! Mastering the Art of Race Driving". It is the best physics-based explanation of car handling I've seen. Based on the laws of physics, each tire has a maximum amount of traction for a given amount of downward force per tire. I want to point out two things that result from this: If you need more traction, you can: (a) get stickier tires, (b) increase contact patch, (c) increase downward force (i.e. the 'normal' vector, perpendicular to the surface). For a given amount of friction, it may be used for some combination of acceleration (forward), braking (backward), or cornering (sideways). By combination, I mean the sum of the force vectors. So, the more friction you use in acceleration or braking, the less you have available for cornering. Unless I hear a better explanation, I think the above explanation above serves as a useful fundamental grounding of tire traction, whether it be on-road or off-road. Question, part 1: Is my summary of the physics detailed enough to be useful without overlooking any key aspects? Are there problems in borrowing the logic of automotive tire grip and applying it to mountain biking? Here is one way to apply this knowledge. As an example, I heard something like this from a video about mountain bike handling (sorry, I lost the link): "pedaling out of a corner gives more traction at the rear wheel" (paraphrased) This seems bogus to me. If you pedal, you are asking the rear tire to use grip for acceleration, meaning less is available for cornering. Question, part 2: Is my logic correct? <Q> So let me get this straight before it becomes a mess: .. <S> increased downward force from pedalling.. <S> When you pedal the downward force is not increased - you are not getting any heavier. <S> You can only increase the downward force on a rear wheel by shifting your body back - this will decrease the downward force on front wheel though, which is good for steering actually. <S> Controlling your body position is easier and more precise when not pedalling. <S> Cars actually act differently while cornering than bikes - bikes lean into the corner. <S> But for the tires and traction that part is the same and you are right. <S> Maximum cornering angle is proportional to the coefficient of friction of the tires to the gravel/road/whatever (this is only affected by the tire tread and tire compound). <S> The faster you want to go in corner the more you need to lean-in with you center of gravity. <S> So if you manage to throw your body off seat closer to the ground the tires won't have to lean that much - see the picture - giving you a better cornering grip. <S> So <S> the correct way is : Pedal before the corner to get your speed, then off the seat and control the centre of gravity for maximum cornering grip (you are not able to pedal now), keep weight on both wheels equally for steering, focus on hitting the corner apex <S> (this is actually the most important part), then pedal again off the corner. <S> With bikes and cornering also the width of the rim plays a role. <S> If running lower pressure to get more grip (bigger contact surface for the treads to bite into ground) with narrower rims you can get a tire blowout (when tubeless) or lose balance as the tire sidewalls have less support. <S> Wider rims provide better support for cornering (but wider are also heavier giving less acceleration). <S> TL: <S> DR: your logic is correct, tire tread veeery important, pedaling is BS, use your body weight to your advantage, lower pressure, wider rims. <A> Adressing your second question where you give the example "pedaling out a corner gives more traction at the rear wheel" and you state that this should reduce traction available for cornering - have you considered that the act of pedaling generally shifts the rider's weight back while also increasing the normal force through putting pressure on the pedals? <S> This is why suspension designers work so much to reduce 'pedal bob' on full suspension bikes due to compression under pedal load. <S> Adressing your first question regarding your understanding/aplicability of the physical principles of road cornering to mountain biking - The physics of how the wheel and tire system behaves may not be terribly different between a car and a bike, but you have to consider that overall the bike system is dominated by rider weight (I weigh ~6 <S> times more than my MTB) <S> so the dynamic repositioning of rider weight has a huge effect on traction. <S> Much moreso than a car where the driver is porpotionately smaller part of the system's weight. <S> So no, there are a few more variables to consider when understanding MTB cornering, and it mostly boils down to rider position. <A> pedaling out of a corner gives more traction at the rear wheel <S> The reason racers sometimes pedal out of corners is unrelated to grip. <S> They do this in order to maximize the exit speed, especially in case they didn't corner perfectly (probably tapped the brakes) and lost momentum.
|
The increased downward force from pedalling and the shifting of a rider's weight may provide more rear wheel traction than is lost from acceleration - thereby aiding cornering ability.
|
What is the easiest to upgrade my chainrings from a double to a triple? I have a 2007 Specialized Tarmac Pro Double and I need some better gearing. I am doing more hill climbs and I feel that I need at least two lower gears than I already have. What would be the most efficient way to upgrade my bike. Would it be easy to get a triple chainring? Will I have to get a new derailleur? What else would I need to change? <Q> You have a couple different options. <S> I think the cheapest would be to switch to a compact crankset which would change the front chainrings from 52-39 to 50-34. <S> I'm pretty sure you could do this while still using the same shifter. <S> Another thing you'll want to look out for is the rear derailleur. <S> You currently have a short cage derailleur, and you may need a medium or long cage derailleur when you go with a compact crankset. <S> I don't think a triple should really be necessary on a 10 speed system. <S> I have triple, but I have an 8 speed cassette. <S> I find in that case the triple is nice because you can still get lots of gear range while still keeping the gears close together, However, on a 10 or 11 speed cassette, this isn't really necessary. <S> Also, according to This post , the maximum cog size of a short cage <S> Shimano short cage is 27 and the total drivetrain capacity is 29. <S> To use a larger cassette, you would have to switch out the rear derailleur. <S> If you used a compact crankset, you should be probably also replace your rear derailler for a medium cage, as your total capacity would be (50-34) + (27-12) <S> = 31. <S> However, if you changed the cassette to a 12-25, you could get away with not replacing the rear derailleur and still getting a little bit lower gearing, although possibly not enough for your needs. <A> You'll need to swap out your left (front) shifter and front derailleur to utilize all three chainrings of a triple. <S> Between the cost of that and the cranks, I think a better option would be to swap out your rear cassette for something with more range. <S> Since you've already got a 12-27 on there, a 12-32 would give you <S> I believe the range you need. <S> My hunch is that you'd be able to fudge it with your current short cage rear derailleur, but a medium cage mechanism will probably be less hassle in the long run. <S> Since cassettes are consumables and need to be replaced periodically, this cost of the just rear mechanism is likely significantly less than the shifter, front mechanism, and the crankset. <A> When you say two lower gears, you presumably have 25 and 27 as the largest gears in your cassette. <S> Does that mean 39/31 would be low enough? <S> If so, the compact with a 34 will get you there, but 34/25 will be too high. <S> Shimano makes a 12/30 10speed cassette in the CS4600 line, which I have coupled to a 50/34 compact. <S> You will be in for a new rear derailleur that way. <S> They also make a 11/32 11speed, but that needs new shifter as well. <S> This might avoid the crankset change, however. <A> Consider instead changing your cassette and maybe your rings, if you're climbing a lot of steep hills and want a lower gear ratio, then what I would suggest trying first is swapping out your cassette with a mountain bike cassette, this may require you to also change your rear derailleur to a long arm derailleur, and you'll need a new chain, but you should change that whenever you change your cassette anyways. <S> If you need a little bit more, then try swapping your small ring with something smaller. <S> You'll save money this way too, because you won't have to change out your crank or your shifter. <A> When I made this change 15 years ago, as well as the new triple chain rings I needed to change the bottom bracket - cotterless square taper type - (which needed to be longer to correct the chain line), front derallieur (needs to be able to cope with extra travel and larger difference in chainring sizes) and rear derallieur (needs to be able to cope with larger total difference in teeth). <S> You will also need to change your shifter to use the new range on the front.
|
Changing the front shifter is required if you want to go from a double to a triple, as is changing the front derailleur. I think that switch to a compact crankset is a much better option. If you switch to a compact I'm pretty sure you can keep the same derailleur and shifter. I wouldn't get a triple crankset, there's a reason why those are dying off of the market.
|
Do certain makes/models/types of bikes get stolen more than others? I was reading this article on the most commonly stolen cars, and having my bike stolen recently, I got to thinking: do certain makes/models/types of bikes get stolen more than others? My bike was a 15 year-old GT Aggressor 2.0 (Mountain bike) and it was stolen out of my back yard. I just have a hard time thinking that someone was seeking out that year/model. It would seem that most bike thefts are crimes of opportunity, opposed to targeted attacks, but I don't see any data to back that up. Also, it seems like for cars, the cars that are stolen the most, just so happen to be the same cars most commonly driven. I assume the same would go for bicycles? Any bike thieves want to chime in? <Q> I'm a lifelong cyclist, including big cities like SF, Oakland, Baltimore, DC, Atlanta, etc... <S> And I've worked in a few bike shops <S> so I've heard several stories. <S> Basically, there are 2 kinds of bike thefts: Crimes of opportunity. <S> Meaning, if a thief thinks they can sell it for $20 or more and they think they can get away with it. <S> These folks will steal any "decent looking" bike. <S> These thefts are atributed to drug addicts. <S> But, I've heard of all kinds of people doing this. <S> Some do it for the thrill. <S> "Professional" bike thieves. <S> The kind that patrol cities and universities looking for bikes that they can flip on craigslist or ebay for good money. <S> They sometimes patrol in vans stealing a dozen in one night using professional tools. <S> They usually steal in one city and sell via craigslist in another. <S> These guys know the difference between cheap bikes and nice bikes. <S> They go for the latter exclusively. <S> Also: <S> No bike is 100% safe, even in your garage, house or apartment. <S> No lock is 100% safe. <S> They just buy time. <S> A cheap lock is worth about 5 seconds. <S> An expensive lock is worth about 10-15 minutes. <S> If the thief has the time and won't be interrupted, they may go for it. <A> It really depends on your area and how fancy your bike is, there are plenty of videos of thieves nicking bikes, like this page . <S> My rule of thumb is: if it's carbon never leave the bike anywhere you can't see. <S> If your bike looks at all fancy, never leave it anywhere you can't see. <S> If it is an average looking bike, make sure you use a D-lock and make sure it is as small as possible, and preferably difficult to get at <S> Never, ever only rely on a chain or cable type of lock as they are just about useless. <S> Obviously don't lock your bike to anything that is easy to just cut off, like a tree <S> These days stuff like <S> battery operated angle grinders are so common, it would take you less that 1 minute to get pretty much any kind of lock off(including D locks). <S> Scary, but true. <S> Thieves have also been known to use small hydraulic jacks as well, will break a D lock in literally seconds. <S> While I was living in London, which is well know for bikes disappearing <S> , I would never actually leave the bike on the street as it was almost guaranteed to go missing. <S> If you are in this kind of area buy a folding bike like a Brompton and just don't risk it! <S> You can fold it and leave it in your house or under your desk at work, you can also take it on public transport everywhere <S> I have been. <S> If you are going to run the risk, make sure that your all your wheels are locked through the rims (not just in the spokes) for both front and back wheels, especially if you use quickrelease wheels (In London my boss lost a rear wheel because of this) <S> I have personally lost a AU$1,000 bike <S> and I swore it would never happen again. <A> Whether or not a vehicle (motorized or not) is stolen depends on how desirable it is and how secure it is. <S> For cars left on the street, the make and model determines both of these factors. <S> For that reason, I doubt that statistics about what is the most stolen bike would be very relevant. <S> Looking for the most often broken locks would be much more pertinent. <S> But even that's not very pertinent, since a badly used strong lock offers little protection. <A> It depends on where you live. <S> In Amsterdam for example the bicycle theft rate is very high compared to anywhere else in the world. <S> Bicycles are owned by nearly everyone and are used as a major mode of transportation. <S> Many people who use the their bicycle for city use intentionally own the "junkiest" bicycle they can. <S> Thieves aggressively target anything that's decent. <S> And they have numerous ingenious, quick ways of opening all locks. <S> The more expensive the bicycle the higher the risk. <S> There's a well established market for stolen bicycles there.
|
For bikes, though, the security is determined by the lock used, which is not directly determined by the make and model of the bike. So yes, in some places, the more expensive bicycles are at a greater risk for being stolen, locked or not. Think about it as if you were nicking a bike, if you have any kind of moderate sized pair of bolt cutters it would take you seconds to get a chain or cable off.
|
Does cycling make one's knees stronger? I'm wondering if riding hard strengthens the knee or causes degradation? I exercise regularly and am in solid physical condition. When strength training off of the bike, I do a lot of leg work including heavy squats, deadlifts, lunges, etc. I've been doing this seriously for 5 years or so alongside riding, mostly road, and it's done nothing but help when I get in the saddle. So, when I get on the bike and ride hard, which is usually 4-5 days a week in season, I have leg soreness (obviously). However, I get sore in the knee - not pain per se - just soreness. The soreness is mostly felt in the structures that hold the knee together, i.e. ACL, MCL, LCL. When I strength train I don't get sore like this - the soreness is all in the muscles, i.e. quads, glutes, hamstrings, as opposed to the ligaments. In fact, I've never done anything besides cycling which induces this type of soreness. That said, is this good in the long run? Am I strengthening my knees or slowly working toward future knee problems? <Q> The key point in your question is I get on the bike and ride hard . <S> There's nothing wrong with riding hard, but it sounds like you're riding too hard for your knees to be happy. <S> Bike fit issues can cause knee soreness, but they also tend to have other symptoms also, such as back soreness or neck pain. <S> The solution is to train yourself to ride with higher cadence, ie to spin the pedals faster. <S> Aim to get into the 90-100 rpm range, or even higher. <S> There are many questions here <S> tagged cadence , the most useful for you may be What is the optimal cadence? <S> and will increasing <S> cadence ability hurt my climbing strength? . <A> If you are doing exercises that cause pain in your knee, it generally could mean one of two things, your mechanics are bad and putting strain on your joint, or your joint hasn't seen such hard use and the tendons, ligaments and joint capsule aren't adapted to such use. <S> Since it sounds like you strength train regularly, I'd guess you have a mechanics issue. <S> You may want to look at your saddle height as well as the setup and type of pedal you are using. <S> While many more experienced riders prefer a large amount of float in their pedals (the play before a pedal will unclip) <S> I found that less float keeps my knees in a better position and reduces the problems I have with mine. <S> Between that and a different cleat adjustment <S> a few years back, I have greatly reduced the strain my knees feel while riding long distances. <S> While I wouldn't necessarily recommend my same setup to you (or anyone), I would point you at your mechanics/bike fit first. <S> It may be very easy to make some simple adjustments and provide your knees with a better position (for them). <A> I'd guess you're doing the majority of the damage to your knees with the squats and that the riding the bike heavily just exacerbates it. <S> Maybe you also just don't really have any other occasion to use your knee ligaments in a way to feel the damage you're doing. <S> I'm a pedal masher too but heavy squats are a real killer.
|
Since you like doing weights, I suspect that you like to push the pedals hard, and this is causing the problem.
|
Should disc brake rotors be removed when packing bike for travel? I've been looking at a few tutorials on packing a bike to take it on a plane, and most of them make no mention of disc brakes. One did specifically mention disc brakes, and recommended taking the rotors off and sandwiching them between two small sheets of plywood to stop them getting bent or warped. Any thoughts on this? Can you just put them back on with the allen key bolts that attach them? Or do you need special alignment tools and a torque wrench? <Q> I have a hard sided case and have done the cardboard box thing <S> (my fat bike does not fit in my hard sided case). <S> Hard sided cases rely on compression to keep everything in place; compression against the flat side of a rotor is not a good thing. <S> Remove the rotors and pack them on each side of a piece of rigid material that will reinforce them and tape the whole thing up. <S> They can be easily put back on with the proper Torx wrench. <S> If this seems like overkill, keep in mind <S> TSA WILL unpack your bike. <S> Do not bother closing a cardboard box before getting to the airport, because they will just cut it open. <S> I leave the box open and leave a roll of tape on top for them to seal it with. <S> I pack any loose items in the box with the understanding that they will be removed and likely reinserted in a different spot inside the box/case. <S> That being the case, you want loose items padded or enclosed in something for when they end up someplace you didn't intend them. <S> I usually make sure to take all the same tools I used to disassemble the bike and pack them as well (usually in a separate padded bag) in the same box/container. <S> I have always favored the center lock rotors because they were easier on and off for travel. <A> I have flown 6x with my bike (Cyclocross Disc) in a soft padded bike bag and never once had issues with the rotors. <S> Echoing the comment by @Daniel, I'd be more focussed on the dropouts and RD and making sure those are supported. <S> You are way more at risk stripping / losing screws than bending a disc. <S> The wheels will be double padded by the wheel bag and the bike bag. <A> A torque wrench is definitely recommended, but some people develop a "feel" for the correct torque. <S> There is usually blue threadlocker compound on the screws. <S> There are small, cheap simple "flexion" torque keys that do the job quite well. <S> My MTB came with one, actually. <A> A few years late, <S> but I thought I'd share my two cents - I recently flew with my mountain bike in an EVOC bike bag, and my front rotor did actually get bent out of shape beyond repair (according the local bike shop). <S> So, I would recommend always removing the rotors. <A> Since posting this question I went on a tour for a few months which involved flying with my bike twice. <S> Both times it was packed in a cardboard bike box from a bike shop. <S> It may have been unclear in my original question, but my question was specifically about the disc rotors, not how to pack a bike in general. <S> When searching elsewhere I found there was lots of info about general bike packing, e.g. remove the rear derailleur wrap it in padding, use a dummy axle for the fork, etc, but I didn't find a lot of info on disc brakes. <S> Anyway, to be safe <S> I removed the rotors, interleaved them with sheets of clean paper towel to avoid contamination (so three sheets total), then sandwiched them between two squares of press-board, which I then wrapped with duct tape. <S> This may indeed be overkill <S> but I'm sure it can't hurt. <S> When I put the brakes back on I did not use any special alignment tool or torque wrench, I just used the torx driver on my multi-tool and put them in by hand. <A> The thing ive found an issue isn't the rotors but actually the headset/stem (especially an integrated one piece setup) being the issue. <S> My friend has a Specialized Venge Vias (disc) and he obviously had to remove the headset to turn the bars to fit into the rigid bike case. <S> Removing the bar/stem means that there's no spare cable/hose <S> so he had to have the brakes bled then re cabled when he arrived there and the same when he got back as they dont like being taken apart. <S> an expensive trip just to take a disc braked bike.
|
To keep the torx screws safe, I put them back in the holes they go in and screwed them in a few rotations. I recommend removing the disc rotors when you travel with a bike regardless of the packaging method. Numerous other MTB friends never remove the rotors either and have not had trouble when flying.
|
Replacing an 8-speed cassette with a 9-speed one to make my bike faster I'd like to make my 8-speed tokyobike Classic Sport city bike go faster so I'm considering replacing the 8-speed cassette with a 9-speed one which can be found on the tokyobike Sport . The bike has smaller 650c wheels and is without a front derailleur. My question is: Is it a good idea? Or is there another, better way to make the bike faster? How much faster will I actually be able to go? What other parts beside the cassette will have to be replaced? <Q> As Blam and Batman have already suggested you will not go faster. <S> The main reason is that your top speed is determined by the number of teeth on the smallest rear cog. <S> The smallest cog available on a normal cluster / cassette has 11 teeth. <S> If your smallest cog already has 11 teeth, then you will definitely not go faster with a new one. <S> If it currently has 12 or more teeth then a new cluster can help you go faster. <S> With practice, you should be able to pedal at 90 to 100 rpm. <S> I venture to guess that this is at lease half as fast again as your current pedaling speed. <S> The advantage of switching to a higher number of gears is that the steps in between the gears is smaller. <S> That can help you find just the right gear for the situation. <S> But it doesn't change your top speed. <S> So my recommendation is to save you money for now while you practice pedaling faster. <S> See also questions tagged cadence , <S> especially What is the optimal cadence? . <A> If you want to go 9 speed, you'll need a Shimano-compatible 9 speed shifter for the rear (i.e. the right shifter). <S> You'll also want a 9 speed chain. <S> Your hub should be fine for the cassette swap. <S> And the 9 speed cassette, of course. <S> In terms of how much faster you should go, possibly none. <S> You really need to keep up a good cadence most likely and you'd be better off switching to a different 8 speed cassette than investing in a 9 speed system. <S> And that would cost way less (you may need to add a few links to your chain, so you may need a new chain, but 8 speed chains are significantly cheaper than 9 speed). <A> I think 8, 9, and 10 are compatible. <S> Sheldon <S> You would also need to switch out the shifter. <S> If top gear is the same it will not make the bike go faster. <S> You just have two more gears between the lowest and highest. <S> Is it a good idea? <S> No it is not worth the cost.
|
The problem with pedaling slowly but getting the 11 tooth cog (if you don't have one already) is that you'll put a lot pressure on your knees and back, which often leads to pain and injury. But the main way of going faster is simply to pedal faster. If you are gong to upgrade might as well go to 10 speed.
|
Mountain Biker wanting to change to cyclo or road? Which one? I ride an inexpensive Trek modified mountain bike and I spend some of my ride on the road and some on the canal, which of course is rather flat. Sometimes at the mid point of my ride I will decide to get off the canal and get onto road with lots of hills. Obviously the mountain bike is not made for this however I enjoy that challenge. Right now I am looking at the Crux Elite EVO. Would that be a good choice, is it worth the money and how much faster would I be on it? Or road bike??? <Q> I've had a hardtail mountain bike for a few years, and used it for all kinds of rides -- singletrack, rail trails, roads. <S> A few months ago I got a cyclocross bike (Norco Threshold) in addition to the mountain bike. <S> So I'm in pretty much exactly the situation you describe. <S> I am enjoying the cyclocross bike <S> and I feel like it's made me about 3-4mph faster. <S> I am surprised that I like the drop handlebars better (more comfortable) <S> than the straight handlebars on the mountain bike. <S> I already had a set of slick tires for the mountain bike that I installed for road rides, and switched back to knobby tires for singletrack rides. <S> If I only had knobby tires, the speed difference would probably be even greater. <S> The Specialized Crux that you're considering seems like a pretty good choice. <S> It has 38mm tires out of the box, which is nice especially since you're used to mountain bike tires. <S> Tires of that size have a much less harsh ride than thinner tires (28mm), and don't slow you down (people used to think that, but research has shown that it's not the case). <S> Two things to consider about that bike <S> : The brakes are cable/hydraulic hybrids; there is a brake cable that connects to a hydraulic piston. <S> I'm not sure if those are as good as regular hydraulic brakes; there is probably a bit of friction in the cable. <S> The other thing is the gearing: <S> for hills you might want an 11-32T cassette instead of the 11-28T. Depends on how strong you are and how steep the hills are. <S> To attach fenders, you generally need eyelets (threaded holes in the frame). <S> If the frame doesn't have any of those, it makes it very difficult to mount fenders. <A> The easiest way to tell is by going to a bike shop and test riding few bikes. <S> I had the same decision to make recently (road or CX), and after test riding, I was confident I wanted to CX. <S> The road bike was noticeably faster, but the comfort on the CX trumped that for me, and it was still very fast (33C road tires, compact gearing). <S> It is also running without problems on trails and gravel(as its supposed to), which is a plus as I can take tours through the woods ( as long as the trails relatively flat, eg for hikers/hourses). <S> I think the main things to consider are: do you care for off-pavement rides?Is the pavement quality good? <S> if there are too many bumps, road bikes can be a pain, while the thicker CX tyres will help. <A> Also look at touring bikes. <S> Road and CX bikes are made for racing. <S> Which means they have a quite aggressive fit which makes you lean over the handlebars quite a bit. <S> Touring bikes are much more laid back and comfortable, while still being very efficient. <S> They have room for racks, fenders, and big tires which can be nice for riding in the city. <S> If the bike show you're dealing with focuses on the Specialized brand, then take a look at the Awol . <S> If you are happy with Trek, then look at the 520 .
|
Finally, depending on what you prefer, you might want to ask to test ride road bikes with a relaxed geometry, that will again be more comfortable. If you care about riding in the winter, go to a Specialized dealer and ask if you can install fenders on that bike, and what size tires will work with fenders.
|
Can an imperfect hub make a disc rotor rub? I had a 160mm disc rotor on a road bike that was rubbing a bit in one spot, not severely, but enough for me to notice. I've tried to true it a few times over the past couple months with little improvement. I finally ordered a new rotor (sram centerline) and noticed it's also touching the pad, possibly more so than the old, but it sounds better under hard braking oddly enough. I checked the new rotor before I put it on and it was straight. I'm wondering if my hub is just imperfect and that's whats causing the alignment issue. Is this common and if so is there a fix? <Q> It could be a number of issues <S> but I doubt you got a bad hub. <S> Check to make sure your wheel is seated correctly in the fork. <S> You could also try tightening/loosening the skewer to see if that may help align things. <S> If all that doesn't work then you can try to realign the caliper if necessary. <S> I wouldn't worry much if its just a little rub. <A> I think @itsthejash has some good tips <S> but I'd also suggest taking the rotor off the hub and making sure there is no dirt or other material on part of the mounting surface of the hub, thus pushing it out in one spot. <S> Maybe use some cleaner to ensure the surface of the hub and rotor are clean on the faces that meet during mounting. <S> Also - when you engage the QR, I find it useful to be putting some pressure down onto that axel to make sure it is perfectly seated - although it sounds like your problem is pretty consistent <S> so I don't think this will fix it for you. <A> Have you tried adjusting it at the caliper ,just dial it back a notch or maybe two ,but make sure your brakes are still effective when you do. <A> Some ideas - mark the rotor where it rubs. <S> then remove and refit the rotor but turn it 90 degrees relative to the hub. <S> Does it rub in the same place or 90 degrees away? <S> I think you'll find the lump follows the hub, not the rotor. <S> Use a straight edge (like a steel ruler) across the flat of the rotor mount to look for any imperfections - they will be really small. <S> If nothing is visible, use a dry-erase marker and colour the whole surface in, then scrape your straight edge over it. <S> There may be bits which scrape clean and bits that don't. <S> The high spots will be scraped clear and the lower spots will remain coloured. <S> Refit the wheel to the bike, with no rotor. <S> You may need to use a straight-edge to see it better. <S> If you find a slight machining error, you want an engineering company to mill it flat. <S> A company that does engine head work should have the right gear. <S> Don't try this with hand tools! <S> If thats not possible, replace the hub and rebuild the wheel, or replace the entire wheel, or simply put up with the scrape.
|
Spin the wheel by hand, and use your eye or by touch to detect if the hub/rotor mating surface varies at all.
|
Creaking when in the saddle I know there are about a million questions on here about creaking while pedaling, but I haven't seen one that relates...apologies if I missed one. I bought a 2011 BMC Streetracer SR02 last year; shortly after I got it I removed the Shimano 105 it had previously, and replaced them with a mix of SRAM Rival and Red (Rival shifters and derailleurs, 2012 Red GXP crank). Since I got the bike last February, I've put about 6k miles on it (both the chain and cassette were replaced ~2 weeks ago). A little over a month ago, I started noticing a creaking/clicking when pedaling, typically beginning when I was about 3 miles into a ride. Nothing was changed on the bike before it started. The creaking occurs about once per pedal revolution (around 6 o'clock on both sides) and stops when I get out of the saddle. It occurs regardless whether my hands are on the bars. I've worked on the bike myself and taken it to my LBS, but we're both running low on ideas. All the chainring bolts were replaced. BB was swapped out with a new one. Red crankset was removed, regreased and re-installed. Red crankset was swapped out for a non-creaky 105 crankset. Pedals were swapped out. Chain and cassette were replaced. Saddle was swapped out. Seatpost was cleaned/greased. Seatpost was swapped out. Wheelset was swapped out for a newer one. Headset was removed, inspected and cleaned. Bottle cage bolts tightened. Front derailleur braze-on bolt checked/torqued. Rear derailleur hanger screws checked/torqued. Wheel skewers swapped out. Replaced the headset cartridges. And yet, the creaking continues. At this point, I feel like I'm pretty much out of ideas (short of calling a priest...). I'm almost positive it's coming from the BB area, but I also know the sound could be coming from anywhere in the bike, given all the tubes. Is it the frame? How would I check to see if it's the frame, rather than one of the components? Any thing else I could be missing? Update: I had a chance to play around with the creakiness when I rode last night (with different skewers in the wheels). It seems like the source of the issue is somewhere in the cockpit area. If I don't have my hands on the bars, the creaking is no different than when I have both hands on the bars. However, it seems that if I put one hand on the bars and shift my weight to that side, the creaking seems shift to that side as well. When I got back from the ride, I put a layer of grease on the part of the stem that attaches to the bars, and I'll check if that made a difference on a ride later today. I'm not sure that will be it, but that would make it easier. Update: Finally fixed! Following a group ride last week, we looked over the bike in a last ditch effort to solve the creaking. Things seemed in order, but the mechanic greased the seatpost clamp and the bolt attaching the front brake to the frame. He also noticed that the stem bolts (where it attaches to the fork) were stripped. Following the greasing, I briefly rode the bike, with no change in creaking. The next day I replaced the stem with a newer one and went for a ride. The creaking persisted at the beginning of the ride, but disappeared partway through the ride after an extended climb out of the saddle. >170 miles later and the creaking hasn't returned. I'm not sure which of the last three solutions finally did it (greasing the seatpost clamp, the front brake bolt or the stem) or whether the grease just needed more time to filter in, but I'll take it. Hopefully no one runs into this issue in the future, but if they do, I hope this saves them the trip down the rabbit hole. <Q> Creaking when only in the saddle - I would check the saddle? <S> A drop of oil into the where the saddle rails fix to the seat can alleviate. <S> If you remove the chain from engaging with the chainset - it would isolate the noise to the chainset / BB only. <A> One thing I don't directly see mentioned that I have done is put a thin layer of grease on the crank spindle where it contacts the bearings. <S> This cured the creaking issues that I had on a previous bike. <S> The only other thing I have had problems with was fork/headset creaking <S> but if you are convinced its coming from the BB it may not be worth looking at. <A> Wow this sounds like a beast. <S> I would inspect the BB area for a hairline crack. <S> It could have something to do with your clothing. <S> Shoes, maybe? <S> Just a crazy guess, 'cause it sounds like you've tried everything else. <A> Decided to answer my own question (with the update), since none of the previous answers specifically addressed the solution (through no fault of their own). <S> Following a group ride last week, we looked over the bike in a last ditch effort to solve the creaking. <S> Things seemed in order, but the mechanic greased the seatpost clamp and the bolt attaching the front brake to the frame. <S> He also noticed that the stem bolts (where it attaches to the fork) were stripped. <S> Following the greasing, I briefly rode the bike, with no change in creaking. <S> The next day I replaced the stem with a newer one and went for a ride. <S> The creaking persisted at the beginning of the ride, but disappeared partway through the ride after an extended climb out of the saddle. <S> > <S> 170 miles later and the creaking hasn't returned. <S> I'm not sure which of the last three solutions finally did it (greasing the seatpost clamp, the front brake bolt or the stem) or whether the grease just needed more time to filter in, but I'll take it. <S> Hopefully no one runs into this issue in the future, but if they do, I hope this answer saves them the trip down the rabbit hole.
|
Since it seems like you've pretty much overhauled or replaced everything on the bike, I would guess that it's one of these two things: Your frame might be developing a crack. But if you are sure it is not this - then perhaps try isolating the noise by using the bike on a static trainer and pedalling. Not sure if you switched the skewers when you tried switching out the wheelset, but I have also heard of skewers causing weird creaks. And I would try pulling (with my hands) on the cranks to try to replicate the sound in a controlled environment.
|
Ideas for consistently popping tubes I ride a cyclocross about 50 miles a week. About half of the mileage is spent on roads, the other half on single track trails. In the space of 3 weeks I have had the tubes pop 5 times. Once the back tube popped while riding on the road near my house. The other four occurred while the bike was hanging in my apartment. I have double checked the interior and exterior of the tires for debris or objects and found none. I ensured tires were inflated to proper pressure and that the rim guard strips were in the correct place. I purchased the bike about a month ago from the neighborhood bike shop. Is there anything I am missing? My current hypothesis is that the tubes degraded in the shop and spring leaks due to age. If that is the case, is it proper to ask the shop to replace the tubes with new ones? Edit: August 2016 Hundreds of miles later on the same tires, rims, rim tape I have not had a single flat. I replaced the problematic tubes and tried to hold all other variables consistent. I was not able to determine the cause of the problems but it does appear the tubes that came installed from the bike shop were more brittle than expected. This could have been due to shop storage. Extended exposure to heat or light can weaken butyl tubes despite being more resilient to weathering and attack than natural rubber. <Q> I had tire busts when I used tubes that were pre-filled with Slime: they burst within an hour to a day of installing them. <S> When I switched to standard tubes and then added Stans <S> No Flats liquid they were fine. <S> This happened twice to me: very strange. <S> I always use Stans in my wheels: either MTB tubeless or commuting/road bike tubed. <S> Is a bit of a hassle with Schraeder tubes because the tubes with removable valve cores are not so common (altho Continental sells). <S> But I use a syringe and a tube to "inject" 50ml of Stans into the tubes: helps a lot with flats (although won't solve this issue). <S> Are you using really light tubes? <S> I've found them more likely to cause problems if your rim/tire combination isn't exactly right. <S> Also check that your tubes really are the right size for your tires: not just the diameter but the width. <S> It might be worth spending a bit more and getting better quality tubes next time: I've found Continental good, and they offer a big range of tubes. <S> Maybe you're using big fat cyclocross tires and tubes mean't for a road tire. <S> They all fit, but will be much more stretched, and more likely to fail, especially if the rubber is not good quality and tough. <S> When you install the tubes, are you maybe pinching them? <S> I partially inflate them and try to install just using my thumbs. <S> Then I go around the wheel and roll the tire back and forth with my fingers and make sure the tube is not trapped under the bead: check both sides. <S> I doubt it's your tires, but try taking them off and running your fingers around the inside: you can feel problems better than see them. <S> I also doubt it's your rim tape, but I often add a layer or two of electrical tape over it: especially if I am using high pressures. <S> If nothing is wrong in particular, I bet you can solve it by using better quality tubes. <A> Not sure what you mean by "popping", are you talking about literally exploding or just getting a cut/pinch/slow leak/etc? <S> If you've had 4 flats while hanging I would guess something is cutting into the tube. <S> I'd try a different tire or pick up a tube from somewhere else and try it out. <A> If you have holes coming up all over the place on two tubes and then bad tubes is a likely cause. <S> Stop patching the tube and put in some new tubes. <S> If the new tubes pop then look for the cause. <S> Always match up the hole to the tire / rim and see if you can find a cause. <S> You could have a case of bad tubes installed by the manufacturer. <S> Best use of a patch is to just get you home. <S> A patch is not as strong as a tube and will not last as long. <S> The glue will dry out. <S> For $6 it is worth a new tube as failed patch is a flat tire. <S> I have a beater bike that I only use in the neighborhood. <S> I use only patch tubes on that bike. <S> I save up tubes and just patch 4 at a time. <S> I will use a patched tube if I don't have a new. <S> Another trick is if the hole is too big to patch then save the valve core and cap. <A> Based on the description you gave in one of your comments , your problems strongly resemble pinch flats, i.e. "snake-bite" flats . <S> Although Sheldon Brown recommends in the linked article mainly to ensure that the tire pressure is correct, I've found that a common reason for this is old or improperly-placed rim tape : If the rim tape isn't doing its job, your tires will be fine for short, gentle rides but you'll get problems once you start to do some longer/harder riding. <S> Very carefully remove the inner tube up and away from the rim, once again without moving the tube in relation to the rim. <S> Check the underside of the inner tube for punctures-- if you find one, find the corresponding spot on the rim, where that part of the inner tube contacted the rim while riding. <S> If the puncture lies directly on top of a spoke hole, your rim tape isn't doing its job; Get some new tape. <S> If your rim has recessed spoke holes , you'll have to be extra careful to get rim tape which is designed specifically for the pressure you intend to pump your tire up to, e.g. Schwalbe High Pressure tape .
|
In order to check if you've got rim tape problems, when you get a flat, very carefully take the tire off of the rim without moving the inner tube: You want to be able to inspect the inner tube in relation to the rim itself. Then I pump it up to max and possibly deflate it a bit if I don't ride it at max pressure. Knowing what the hole looks like could help point to some cause.
|
Is a car "perfectly entitled" to turn left around cyclist (I'm in the UK so we drive on the left) This morning a driver pulled up alongside me (to my right) at a junction. As soon as a gap came available, I pulled out to turn left and he did the same, coming within a couple of feet of me as we turned. I verbally objected (what the ..?). He confronted me a little further down the road, and insisted he was "perfectly entitled" to turn left around a cyclist who is also turning left. Is this correct? This was from a single lane road, turning into another single lane road. <Q> The UK Highwaycode states: <S> Using the road: <S> Turning left Rule 182 <S> Use your mirrors and give a left-turn signal well before you turn left. <S> Cyclists, motorcyclists and other road users in particular may be hidden from your view <S> It seems quite clear to me that the driver should not have pulled up to the right of you, which is essentially an overtaking manoeuvre, if he intended to turn left, no matter what you were planning. <A> Highway code rule 163 give motorcyclists, cyclists and horse riders at least as much room as you would when overtaking a car <S> He wouldn't overtake a car as it was turning left, so he shouldn't overtake a cyclist; 2ft is not an adequate safe margin. <A> In addition to the two answers citing the Highway Code - the key words are 'perfectly entitled'. <S> The answer is 'No'. <S> The HC does not have the force of Law in the UK, but infractions of the Code will be taken into account if a driver's actions result in an accident or an intervention by the Police. <S> Drivers have a duty of care to other road users, and overtaking without leaving sufficient clearance puts other road users (in this case - you) in danger. <S> It's worth noting that a number of the cycle fatalities on London's roads over the past few years have occurred at junctions where the cyclist was attempting a left turn and was 'overtaken' by another vehicle. <S> The solution for the cyclist is to move to a 'control' position in the centre of the lane about 5 to 10 metres out from the junction, thus forcing following vehicles to remain behind. <S> Do not wait at the kerb edge or creep up on the inside of waiting traffic. <S> This is why many junctions have marked cycle space in front of the lane. <S> You maintain the 'control' position all the way around the turn, returning to a normal riding position of around a metre out from the Kerb when it is safe to do so. <S> The 'control' position is taught by Bikeability instructors as part of the Government recognised cycle instruction programme offered in UK schools. <S> It's not just for kids, it works, use it.
|
Do not overtake just before you turn left and watch out for traffic coming up on your left before you make the turn, especially if driving a large vehicle.
|
Making a Cannondale BadBoy ride softer I have a Cannondale BadBoy with slick tyres, no suspension etc. On roads the ride is fine, but I do less of that these days and more along tracks (e.g. unmaintained paths, towpaths etc.). On non-metalled surfaces the ride is incredibly hard and I get incredible vibration through the forks and frames. What are my options for modifying the bike so I can mitigate this. Will suspension forks soften the whole ride or just the vibration through the handlebars. My local bike shop recommended knobbly tires, a suspension-fitted seatpost and/or front suspension forks. Or should I just keep the bike for road use and get something more appropriate ? <Q> Wider tires are the first thing to try. <S> The BadBoys are basically rigid mountain bikes with 622mm wheels and narrow tires, so you could also put on mountain bike sized wheels and very wide tires. <S> With a second set of wheels, it's easy to change between road and off-road riding. <S> You could install a 29" suspension fork, but that would change the bike's geometry. <A> I would start with the biggest knobbly tires the frame and wheel will take. <S> It came with a 28 mm. <S> I doubt there is enough clearance to put a mtn 2.2 on it <S> but even a 35 mm or 38 mm is big step. <S> In knobby a 35 mm will be sold as a CX. <S> Run the tires at less than maximum pressure unless you are over like 180 lbs. <S> Those slicks are not the correct tires anyway. <S> For a fairly small cost you are going in the right direction. <S> A suspension fork will change the geometry and is expensive. <S> As for a suspension seatpost you are probably riding the ruff stuff out of the seat already. <S> If you are going with a separate set of wheels <S> then tubeless to run at a lower pressure. <S> But now you are starting to spend some money. <S> Depending on how big of tire the frame will take pick the proper rim width. <S> I would just start with some tires. <A> Running suspension with narrow tyres is a fool's game: the store is trying to chump you. <S> How far a tyre pressure decrease will take you depends on your weight. <S> To be honest, the BadBoy is just a design driven by marketing. <S> It's aimed at people scared to ride drop bar bikes who still want to go fast and imagine thin tyres will help them do that... <S> In fact tyre width has nothing to do with tyre drag - wide tyres can be extremely fast (it depends on the materials used and other details of construction http://www.schwalbetires.com/tech_info/rolling_resistance ) until you get up to speeds where minor differences in air resistance due to width matter - which you won't on a flat bar bike! <S> These differences only come in to play at serious racing speeds. <S> (The fastest wide tyres are probably Schwalbe Almotions; they cost several times more than the cheapest.) <S> Good suspension components are expensive and usually require a lot of maintenance, and cheap ones can be dangerous. <S> .. <S> Probably avid suspension - good suspension is expensive and requires regular maintenance. <S> ... <S> A really good bike for this sort of job is an old 26" mtb with no suspension, bought off <S> ebay - Kona and GT are good bets. <S> Or you can buy a new boutique adventure bike that is a copy of one of these for about 5 times the price. <S> Also: if you're going to ride on gravel etc, get some tyres with some knobs for grip - they will cost you speed and handling on the road, but washing out on gravel can be painful and dangerous.
|
If you're a light weight type of guy, try fitting the widest tyres you can and dropping the pressure. About suspension forks, with current geometry there isn't much room for the suspension to work. Otherwise, buy a bike with room for wide tyres.
|
Can I use a Brompton bike with a trailer like the Thule Chariot Cougar? I wonder if I can use a Brompton bike with a trailer like the Thule Chariot Cougar? It uses the so called Thule Axle Mount and I wonder if it is compatible to the bike. At this point, it is just advanced planning and I can't test the possible setup. What do you think, any experiences? <Q> I'm going to say <S> yes based on this photo. <S> It looks that the hole is big enough to pass over just about any axle, quick release or nutted. <S> I think what is throwing you off is that it comes with a quick release skewer that is longer than what is typically used for wheels. <S> You may not need that provided skewer. <S> Burley uses a similar one <S> and I was able to put the hitch on a Jamis bike using the skewers that came with the bike. <S> If your bike has the internal gear hub, it probably has anti rotation washer (special washers to keep the axle from turning). <S> This hitch would mount to the outside of that washer. <A> It has the standard adapter (similar to the one in the picture above) and works fine. <S> I didn't have to do any adaptations. <A> How much "like" does it have to be? <S> I have seen trailers that clamp onto the seat post. <S> These have the added advantage that when unhooked from the bike, you can use it like a hand truck. <S> I used to go grocery shopping with a Burley axle-mount, and had to rearrange the groceries when I lowered the tow-bar to axle height. <S> In one model I saw, the cargo compartment was easily removable from the frame and had straps to make it a backpack. <S> UPDATE: I now have a Cyclone IV Chubby . <S> On the road, my supplies go inside it. <S> When I get to an airport, I empty it, fold the Brompton and put it inside. <S> Surround it by whatever else will fit and check that in. <S> The rest goes in the backpack for carry-on. <S> Downside: excess baggage fees Radical Design makes other trailers. <S> This person uses a child trailer with Brompton <A> This should work. <S> I use the Thule Chinook 1 with my Brompton folding bike. <S> The only inconvenience is that the front wheel is best not folded down but removed. <S> The clearance with the ground is too low. <A> Yes i can confirm that a Thule Chariot goes great on a Brompton. <S> The clearance from the road to the coupling is clearly lower than on a larger-wheeled bike but it handles well and has not slowed us down at all.
|
But when you remove the front wheel, it works perfectly. I have a Chariot (now Thule) cart attached to my Brompton (with internal gears). Based on this experience I would say yes! The only issue is that the cart leans forward due to the 20" wheel but my little one does just fine.
|
(racer) Standard vs compact crankset: Increased leverage for same gear ratios true? I'm a road and mtb regional racer about to have a go at my first road endurance nationals very soon. I'd like some educated scientifically validated answer on a matter that has been on my mind ever since I got a new bargain race bike that unfortunately came with a compact crankset. I actually went from 39/53 + 12/28 10speed to 34/50 + 11/28 11speed. On paper I'm a lot better off with the new setup, since I'm using the exact same spacing on the cassette with the benefit of the 11t cog i didn't have, which, even though doubled with a compact gearing upfront, ends up giving me a lot more headroom in bottom and even a tad bit more top speed. My coach has always insisted that even on same gearing ratios, when compared, a larger crank ring with a smaller cassette cog end up giving you higher leverage and ultimately better power transfer or whatever mechanical benefit. Last Saturday, trying out hard climbs on fresh legs with about same gear ratios on the 50 vs my 34, actually felt less efficient on the 34 for some reason, mind you same cadence, intensity, gradient. What's your take on all this? If the math says gear ratios are same, are the actual ring and cog sizes irrelevant? Is it actually beneficial to switch to my standard crank due to increased leverage? Thanks a lot, lads! <Q> While it's true that a larger chainring will have slightly less friction and thus slightly more efficiently, it's an extremely negligible amount, that you wouldn't be able to feel. <S> More importantly, are your crankarm lengths different on the new crankset than the old? <S> That makes a much bigger difference. <S> For example, if you've went from 175's to 170's, that will be a noticeable difference that could more likely explain what you're feeling. <A> Talking about science, there are two factors here: <S> moment of inertia - smaller and lighter cogs in a compact crankset mean smaller moment of inertia, which in turn means that you need smaller force to obtain the same acceleration. <S> In this aspect a compact crankset gives a slight advantage. <S> Note: this parameter is practically insignificant when it comes to maintaining pedaling speed - it's all about acceleration. <S> drivetrain efficiency <S> - I've already written a post on it somewhere, but in short: with the same gear ratio drivetrain efficiency improves with larger rear cog (lighter gear at the back). <S> To see the overall effect, we'd have to make calculations for each crankset, power input and gear ratio separately, but I'd argue that drivetrain efficiency will be a little more important here (it's due to friction force, which is there all the time), so a compact crankset could be a "slower" option. <S> However the differences in both cases will be barely noticeable on the road, and even less noticeable off-road. <S> Or at least placebo effect can give a feeling of much larger difference than even extreme cases of the above factors - if you didn't know which one you're using, you probably wouldn't be able to feel the difference. <S> So unless you're fighting a Marginal Gains war in a world tour peleton, it's not a thing worth worrying about. <A> The larger chainring reduces drive chain friction - so is more efficient. <S> This article from cyclingtips lists a study which demonstrated this <S> You can see the effects of this in the peleton where riders like Froome are favouring assymetric rings to give them periods of greater efficiency and reduced torque during pedalling
|
Since with a compact crankset you need relatively smaller cog at the back for the same gear ratio, a it will have a slight disadvantage.
|
Electronic bike keeps getting flat tire on the back A month ago, I got my first flat tire on the back tire on my electronic bike and I have fixed it, it was a Nail. Yesterday I got it again, it was a hole in the whole tire, so I changed the tire and the inside. Today I got it again but I see no hole in the tire. What do you think it is? <Q> You should try to make sure that you have the tires properly inflated -- on the high end of the maximum PSI the tire can handle. <S> Try to ask your LBS when you're replacing the tire what type of puncture you're getting. <S> If you are getting pinch flats, then you need to think about inflating your tires to a higher pressure. <S> If that's not possible, you can also explore getting wider tires. <S> If you're getting road debris punctures, then kevlar belted tires will help. <S> Also, as ow3n notes, having some sealant inside your tube might help although I find that this often just creates a huge mess when you get a flat that is too large for the sealant to contain. <A> Head to your local bike shop and ask them to replace your tube with one that has a removable core. <S> Then add some (1-2 oz) <S> Stan's Sealant inside the tube. <S> This looks like a good how to. <A> If you replace the tyre with a tough (kevlar belted) touring tyre <S> this is likely to deal with debris punctures. <S> These are more likely if the tyre is quite compressed as it rolls because of the flatter contact patch. <S> In addition a touring tyre will be able to run at a higher maximum pressure than a similarly-sized city / general-purpose tyre as was probably supplied, reducing the likelihood of pinch flats. <S> So I suggest a marathon plus tyre on the back - probably around a 35mm or equivalent. <S> I'd put one on the front at the same time. <S> Also don't forget to unweight the saddle on bent legs as you go over rough stuff <S> (potholes etc.). <A> Sounds like a string of bad luck. <S> Two punctures within a month is not unheard of, especially if you're riding in city or other area where debris on the road is common. <S> The last flat tire is most likely to be problem with installation of the new tire and inner tube. <S> Possible trouble areas are pinched inner tube, valve not lining up properly with hole in rim or something caught between inner and outer tube. <S> If you can, check the location of the leak in inner tube and see if you can find any marks at the same place in the inside of tire. <S> A bit of stone etc caught between the tire and tube can break the tube but doesn't make a hole in the tire.
|
Air it up, give it a good spin and you will have a tire/tube that can withstand most punctures from random automobile road detritus. If you have an e-bike with a rear hub-motor (and with the battery pack over the rear tire), you should note that you have considerable unsprung weight on that rear tire. You might of course just have been unlucky.
|
Grabbing the attention of the person ahead of you while bicycling Normally you let the bicyclist/walker/jogger ahead of you know that you are about to pass them by shouting "passing" or even by just ringing the bell on your bike. This is done as a courtesy since many people do get scared/shocked if someone just zooms by them without notice. It's also a safety issue since the person could accidentally or knowingly go to the left side of the path and you'd run into them. For example, they could see a cute duckling on the left grass and start walking over towards it forgetting about looking behind them and bam, an accident! Ride to the right on multi-use paths and warn other cyclists, walkers, runners and path users before overtaking and passing them. Call out “passing” or ring your bike bell. From https://bicyclecolorado.org/learn/colorado-bicycle-laws/ However , now a days many people (usually younger people) will be blasting music in their ears through their headphones. So I've noticed that many times these people don't hear me shouting at them that I'm passing. Here's three options I've came up with: I could just keep going at the same fast speed and just blame them if they get hit since they are the ones that thought their music was more important than safety or listening to the sounds of nature. I could slow down to a safer speed and slowly pass them reducing the chances of an accident. I could carry some small pebbles with me and then just chuck 1 or 2 of them about 6-8 feet ahead of them to grab their attention. I don't really prefer any of these three options, is there a better way to grab their attention when shouting doesn't work, while maintaining the same faster speed? <Q> You already known the answer (2), but do not seem to care much for it. <S> I would suggest When approaching, slow down to an appropriate speed. <S> Make an attempt to notify (bell or calling out), even if they have head phones on. <S> If they do not respond or move, then further adjust your speed and position on the path appropriately to ensure you can safety pass. <S> Because you are moving faster, you have the most momentum and will therefore inflict the most damage in the event of an accident. <S> If the other party is unaware of your presence then you bear most of the responsibility here. <S> ( A couple weeks ago I attended a multi-use path crash where one user had their face caved in due to the speed of the other user. <S> You would be surprised the damage that can be inflicted. ) <S> The reason I would call out or ring a bell even if they may not hear you is liability in the event of an accident. <S> Finally, it pains me that many complain about the way that some motorist bully cyclists on shared road ways, then go on and do the same to pedestrians or other slower users on shared pathways. <A> I know you're looking for a different answer, and I'm not trying to be preachy, either. <S> This just touches on a subject that's been on my mind a lot lately. <S> There's no fool-proof way to get pedestrians to move out of your way. <S> No matter how loud your yell/bell/horn/brake noise is, there will always be a chance that someone won't react as you predict. <S> Just like vehicles on the road have an obligation to maneuver safely around us cyclists, we have an obligation to do the same with pedestrians. <S> It's not the pedestrian's job to get out of your way. <S> If you don't want to deal with pedestrians on MUPs, ride on the road or a cycling-specific path. <S> The minor inconvenience you'll face is worth not injuring yourself and/or others. <S> Not to mention how much better the working relationship between motorists, we cyclists, and pedestrians could be if we all practice what we preach to drivers. <A> Well there is only one rule - adjust your speed to the situation . <S> Doesn't matter if it's falling rocks, a sudden animal crossing road, people, deaf/earphone people, kids, oil on road behind corner... <S> You don't even have to use noises to notify people <S> - it usually surprises them and they make sudden moves. <S> Just pass them at safe distance with safe speed (I would pass elderly with greater speed than kids, because it's not likely they will move quickly into your trajectory). <S> Use your prediction and treat everything the same - have a total control what's around you and what can intersect your path, no matter what it is. <A> Buy a very loud alarm and, if the person ahead is wearing headphones, blip it as you approach. <S> Note : <S> such items can be purchased at Maplin stores in the UK http://www.maplin.co.uk/ <S> EDIT in response to Andy's feedback. <S> The original question is essentially flawed. <S> It seems to ask "How can I attract someone's attention when they can't see, feel or hear me?". <S> The answer is "You can't". <S> NOTE <S> I deleted my facetious answer about using a long stick.
|
But if you're going to share a MUP with pedestrians, you have to slow down when passing if you can't get them to move over safely, period. Given that, by definition, they are facing away from you and physical touch is excluded, the only recourse is to make a sufficiently loud sound so that they can hear it over the distraction. The reality is that you are the fastest user on the shared path thus you bear the most responsibility.
|
What's this mark on my chainstay? I was cleaning my road bike (cannondale supersix evo) and noticed a marking on my chainstay and I'm not sure what it is. Scratching it is a little rough compared to the carbon around it. This was not there before I did take my bike into the shop a few months ago, since the wheel was sitting really close to the non-drive side chainstay, and they said it was a non issue. This was when it only had a small scratch. Now it's turned into something like this. Should I be concerned? I have a big ride coming up and don't wanna miss it!! Here are some pics: <Q> I have a Cannondale Supersix Evo and I've had issues with tires rubbing in that exact spot. <S> The frame will accommodate a 25mm tire, but the clearance is very tight, so you really have to pay attention to keeping the wheel trued up. <S> I've also found that the stock wheelset (Mavix Aksiums) flexed enough when I'm cornering hard to cause a little rubbing even when the wheel is near-perfectly true. <S> For a little while, I put some protective tape on the chainstays (I used ISC Racers Tape), but I eventually just switched back to 23mm tires. <S> I like the ride quality of the wider tires, but replacing the protective tape periodically got to be a bit of a hassle. <S> To answer whether or not it's safe to ride, it LOOKS like it's just through the paint. <S> If that's the case, cover it with some protective tape to prevent it from rubbing into the carbon, and you should be good to go. <A> It's identical to what I have on my cyclocross bike from running too wide tires, except my rub damage is to aluminum. <S> Since you already checked the skewers, check the dish of the wheel to see how close its coming to the chainstay, also check if there is play in the axle/hub, that may cause extra flex. <S> A lot of power can cause frame flex and tire contact. <S> Those tubes down there are pretty beefy, but a lot of rub will grind right through. <S> I'd say its safe, for now, but keep an eye on it. <A> Short answer: <S> That is the tyre rubbing mark. <S> This happens when the clearance is too little to allow any error in assembling the rear wheel. <S> I have repaired a few carbon frame and happy to tell you that it is very likely that the damage is superficial. <S> It appears to be a smooth surface, which means the worn out part is still at the epoxy/laminating epoxy resin. <S> Just make sure that the wheel is true, and assembled correctly to prevent further damage. <A> If you look closely (especially at the last pic), you can see that the tire has rubbed into the fourth layer of material. <S> Black, white, black, gray. <S> It's clearly gone into the carbon. <S> I would take it over some harsh bumps, to stress the frame beyond anything it would experience normally. <S> If that works out okay, put some tape over the spot and don't worry about it. <S> (And, of course, true your wheel.) <A> Check the axle has not drifted over. <S> You need some cone spanners and you can check. <S> There should be the same amount on both sides where the axel fits into the dropout. <S> Another point is the dishing of the wheel. <S> Rear wheels are usually dished slightly over . <S> If you have done some wheel truing lately or someone else has, make sure its not dished too far over. <S> Check <S> there isn't a small buckle in the wheel hitting at that point only. <S> Another idea is to change down the size of your tyres as previously mentioned, or go for a slicker tyre. <S> Short term solution to protect the frame is put some gaffer on it but to be honest your tyre shouldn't be rubbing, especially not on carbon. <A> You should seal the carbon fiber to protect it from water. <S> Water will cause the carbon fiber to swell. <S> You can seal with nail polish or a lacquer. <S> This is a video on repair . <S> I think tape (alone) is a bad idea as it will hold moisture. <S> I think a jubilee clip is a bad idea as it will tend to crack the finish. <A>
|
It looks like the tyre has rubbed due to the wheel being pulled over,this is caused if the skewers were not tight enough.recentre the wheel and re tighten the quick release skewers Yes it is safe to ride on it for another thousands of miles. Looks like the finish is rubbed off.
|
Tubular tire on hooked rim I just bought a new (second-hand) bike (Orbea Asphalt sport) and I was looking at the tire and found out it was a tubular tire, a Continental Grand Prix, but on the sides you can read 'only mount on a hooked rim'. Is it possible for a tubular tire to be mounted on a hooked rim? <Q> Tufo makes tubular clinchers. <S> Clement made something similar in the eighties, called the Ritmo, I believe. <S> I don't think Continental does, I'm pretty sure they're just regular clincher tires. <S> You can ride tubular tires on clincher rims in an emergency, but they'll roll off the wheel if you're not very careful in the corners. <A> Tubular tires are "all in one" tire where the inner tube is sewed inside the tire. <S> Regular clincher tires are very similar, but require an inner tube to contain the air. <S> So a tubeless tire does require a hooked rim, but they are not tubular tires. <S> Additional detail : clincher tires can be installed in tubeless rims with no problems. <A> It's not a tubular tire. <S> Tubular tires are held to the rim with glue and are pretty much only used in racing due to their cost and the hassles of replacing them when they flat. <S> Clinchers (including tubeless clinchers) rely on a wire or Kevlar bead in the tire and a sidewall on the rim to hold the tire to the wheel. <S> Some rims have a lip - or hook - on them to help hold the tire on the wheel, especially in the event of a flat. <S> Using a tire intended for use on a hooked rim on a rim rim that does not include a hook/lip could result in the tire peeling off in the event of a flat. <S> If this happens at high speed the results could be disastrous.
|
Tubeless tires look like regular clincher tire and hooks in specially designed rims; these tubeless tire and rim provide an airtight seal so they can be inflated without an inner tube. I think you are confused between tubular and tubeless .
|
One Month to Build Endurance I've got a seven day cycling session in the Alps coming up in about a month. Unfortunately, I've not been great about getting on the bike in the past month (or even the past year, to be honest). From many years of cycling, my fitness is still quite good — enough that I had a great double century last month, before I took a month-long break. But I'm still far short of where I'd like to be, especially in the climbs. What can I do over the next month to maximize my climbing endurance for this trip? On average, a day will be about 8kft of climbing, with the biggest day being somewhere around 16kft. Should I be focusing on long-distance riding at endurance pace? Hour-long hill repeats? Something else? If you had a month to prepare, what would you do? <Q> I'd say you could go with HIIT (high intensity intervals) on a treadmill. <S> For example a particular training I like and find helpful is: 6-8 sets of: 1 minute very fast (18km/h for me) 1 minute middle speed (12km/h in my case) 1 minute slow (8-9 km/h) and no stops in between. <S> That's a very good yet pretty hard training. <S> Do not more than twice a week. <A> Appart from training <S> you should make sure that you have enough easy gears available. <S> Being able to pedal (relatively) easy with high cadence does make a lot of difference, both in efficiency and endurance. <S> If your gears allow you to do that then I also don’t think that there is much specialiced training you can/should do for climbing. <S> Using something like the typical road bike gears with 53/39 chainrings and 11–25 cogs in the alps is a bad idea. <S> But I guess you know that already. <A> Just remember to taper way down and don't do anything too intense in the week before your trip!
|
Since you already have a great base, I think you will see the most benefit from doing some high intensity intervals and some moderate intensity hill repeats.
|
Chain length and cassette tooth count relationship A little context first: I'm going to be riding in the French Alps and plan to tackle some of the classic climbs (Alpe D'Huez, Galibier, etc) next month - I currently have a Campagnolo Athena 50/34 (compact) chainset paired to an Athena 11 speed 11-27 cassette on the rear. None of the drive-train components are anywhere near worn enough for that to be an issue. Additionally, the rear derailleur cage is able to deal with the full range of the 11-29 cassette so this is also not an issue. What I am considering is swapping out the 11-27 cassette with an 11-29 to give myself a little extra in terms of 'safety gears' - better to be overgeared than undergeared in my opinion! My question is this: will I have to replace the chain when replacing the cassette, for example due to chain length? My reasoning is that since I will only ever use the 29 tooth on the cassette with the 34 tooth chainring, that chain length should not be an issue. As above, the chain is not in need of replacement due to wear, so that is not part of the consideration. Perhaps I'm missing something? <Q> I agree with @ <S> Nik that it should not be an issue. <S> You can verify it by shifting the chain to the big ring in the front and the large cog in the rear. <S> With your hands fold the chain over itself to simulate it being two links shorter. <S> Observe the rear derailleur. <S> You should see two bends in the chains as it passes around the jockey wheels. <S> If the chain passes thru the jockey wheels in a straight line the chain will be too short. <A> My reasoning is that since I will only ever use the 29 tooth on the cassette with the 34 tooth chainring, that chain length should not be an issue. <S> I wouldn’t count on that. <S> It just needs one sleepy, careless moment where you shift and shift and shift while being on the big chainring. <S> I’ve tried too-short chains on a bike stand with manual pedaling <S> and I was able to engage the gear <S> but it does get stuck halfway through because the chain is just too short. <S> When you are pedaling with your legs something is bound to break in such a case. <S> That being said, I would (and did) still use it as a temporary solution. <S> You just have to be careful on the big chainring. <S> There are people who use multiple chains and swap them every 1000km or so to wear down chains and cassettes evenly. <S> Otherwise: Go ahead. <A> The only issue would be if your current chain length assumed you would not use the 27 with the 50, while now you presumably might do so now. <S> In that case you might be one short. <S> I would change the cassette, then put the bike on a stand, and try it. <S> I find it hard to avoid occasional cross-chaining, but you may not. <S> If adding a link solves the problem, that is so easy that you should do it. <S> It is harder <S> if the derailleur can't handle the range-now you need to buy a longer cage derailleur, which is some money.
|
A minor effect is that a used chain will increase wear of the new cassette.
|
How to deal with motorist's road rage (after prevention has failed) A few weeks ago I had my first experience where I really worried for my well-being at the hands of an angry motorist-- so, what can a cyclist do when being threatened and followed by a motorist? Background I was riding on a road with a lot of parked cars as well as driveways, so I was riding somewhat more "center" than what a certain guy was happy with, because he shouted at me to get off the road and onto the bike lane after honking and trying to overtake me. I told him that I don't have to because cyclists have the same legal rights to surface roads that motorists do, and then rode even closer to the center to keep him from dangerously trying to pass me. He then began shouting obscenities at me while driving behind me, so I gave him the one-fingered salute, which he, his wife and son all reciprocated in a perfect Kodak moment. I admit that what I did was the antithesis of mitigating road rage, but I also admit that, until now, I (foolishly) never expected to meet someone on the road who might willingly hurt me: At the next traffic light, he told me to pull over so we could discuss this face-to-face, and I said: "No: I don't have to do that either". What began to scare me is that, after losing him in traffic, he managed to catch up to me and began following me for a very long time and glaring at me. Eventually I pulled quickly off onto the sidewalk and put my keys from my bag into my pocket (it was the sharpest thing I had), but luckily he had to follow the flow of traffic and he didn't meet me again on the road. Solutions My safest course of action would have been to avoid provoking the driver in the first place, but I honestly had no expectation that telling a driver about traffic laws could provoke someone into a potentially-murderous rage; Even if I became a mouse on a bike, the possibility of (inadvertently) enraging someone will remain, no matter how small it may be. Therefore, my question is what someone can do in a case where even trying to prevent road rage has failed and they now face the unadulterated wrath of the Gods of the Exploding Dinosaurs-- I really don't think the guy in the story above was intending on "discussing" the matter if he caught me off my bike. <Q> Pull off the road sooner. <S> Sure, you have a right to be there, but it was quite clear that this creep wasn't prepared to accept that. <S> Your safety is more important than taking the lane. <A> Call the police. <S> Get his plate number, his description and report him to the authorities. <S> Idiots like that are too thick to talk to, it takes an officer to get through to them. <A> Since buying a camera i have experienced very few instances of road rage. <S> As soon as a driver starts with the anger i just point to the camera and ask them to smile for youtube. <S> you can get decent helmet cams for arounf 30 quid if you look around. <A> Go in the wrong direction in a one-way (using the sidewalk if need be) <S> All these are hard for a car to keep up, sure you might annoy some pedestrians and might be illegal in some places, but it's still better than having the crap beat out of you.
|
Go off the road using pedestrian's facilities (sidewalk, park) Change direction quickly or go back the other way on the same road Noting his license-plate number and car make/model as he vanishes into the distance isn't a bad idea either, in case you see him again. Call the cops while you're riding, tell them you fear for your safety and let them hear the idiot shouting at you. I thankfully never was in that situation, but if the driver doesn't let you go or is getting out of the car, use the bike's advantages over the car :
|
Bike for college campus I'm looking for a good bike to use to get around campus and use on the local trail which is about 10 miles paved and unpaved and goes around a lake. Preferably under $300. <Q> If your campus is like most I have ever heard about, you want the cheapest bike that will do the job. <S> Bike theft is a common thing everywhere but campuses where a lot of young people are in need of bikes are certainly not less risky than average. <S> Most students I know look for second hand bikes, either at the university, online or <S> where they grew up/have their relatives and friends network. <S> The brand of bike is less important, I guess you know better than I do what kind of bike you like for that. <A> I had a BMX bike for two years in college and no one wanted to steal it. <S> They are fun to ride, can get you across campus through any terrain, and are small enough to fit inside closets and crevasess if you forgot your lock. <S> If that's not your thing. <S> Try an older road bike off of craigslist. <S> Something that you can maintain yourself, but not too shiny to get noticed. <S> Make sure you replace all the quick release parts. <S> I had a 20 year old Specialized road bike before going to the BMX. <S> Before that, I had a 2 year old Mongoose that got stolen piece by piece. <A> Especially considering the theft issue raised by Willeke, I'd say hands down the bike for you is a rigid mtb. <S> That's what I ride. <S> I live in a high-crime city, and ride it on fairly technical trails. <S> I would buy used. <S> I would probably put some skinnier 26x1.5 tires on it, depending on how rough the unpaved stuff is.
|
To most common thieves it does not have a high value since it looks like a kids bike. You want something light and with less moving parts so that way there is less to go wrong. You could probably get a decent used one for less than a hundred bucks.
|
Why are foot-long pedals not widely used? A lot of effort and resources go into making cycling shoes stiff, presumably to keep the foot in a suitable shape and spread the force across the sole. It seems like it would be possible to achieve a similar effect by making pedals long enough to support the entire foot, with or without a retention system. However I'm not aware of the existence of any pedals like that, so I suppose there must be strong disadvantages to them that I haven't thought about. <Q> I'd wager the two biggest reasons you don't see foot-sized pedals are the increased rotational weight, and the difficulty you would have catching the pedal with your foot before it struck the ground or the front tire. <S> I'm sure someone tried this once and promptly scrapped the idea after the foot-sized pedal struck something. <S> Pedals need to be stiff and durable, which is fine. <S> But if pedals had to be stiff and durable and large, they would probably end up being heavy, so it makes sense that most pedals you see are small and compact. <S> Shoes already do a great job of interfacing with and conforming to your feet, and it's easy enough to make the sole stiff with plastic, fiberglass, and carbon fiber. <S> All of these factors combined explain why we have small pedals. <A> One big difference is where the force is applied. <S> In a conventional pedal, you press down using the ball of you foot. <S> You would be losing the power and flexibility that your ankle can bring. <S> Being clipped in the pedal also has many power and security advantages. <S> Does your footlong pedal in your scenario has a way of being clipped ? <S> In that case you still need strong shoes with a sole, so why have that big of a pedal when you can have a single smaller point of contact ? <A> You still want the axis approximately at 30% of your feet's length - that's when pedalling is most efficient. <S> Just try to pedal with your feet's centre or back on pedal. <S> Full-foot pedals accordingly will be asymmetric, implying they will be one sided and will tend to point to the ground with their backs when you're off-pedal making, as mentioned before they will then scrap over the ground. <S> the stiffer your shoes <S> the less they will compress each time you push onto the pedal. <S> The energy this compression costs is proportional to how much your soles are compressed. <S> This compression will be almost inelastic, meaning it will just heat up your shoes instead of pushing you forward. <S> A rough estimate of the energy you lose: each half crank turn the pedals move by 34 cm down (twice the crank length), but due to compression of the sole, your feet move 34 cm + d. <S> d=5 mm gives only 1.5% loss that should be hardly noticeable, it definitely feels like more. <S> My argument might miss something or ergonomics is involved, which is hard to put into equations.
|
In a foot-long pedal you would have to center the axle so the pedal stays level, but that would mean that the force would be applied by the middle of your foot. Another reason shoes are stiff is efficiency:
|
Group of Bikes: Is 3x1 an option? I'm an RA for a dorm that is considering buying a number of bikes that would be owned by the dorm and lent out to students. I will be at least in part responsible for maintaining the fleet (about 10 bikes) so I was thinking it should have fewer things to break. I considered getting single speeds but I think students might want to be able to change gears from time to time (though there aren't many hills here). I was thinking maybe a triple crank and single speed in the back might be an option. This would mean only a front derailleur so fewer parts to fix. Has anyone tried this? I couldn't find anyone online mentioning it. I think a 1x9 with a 34T chainring is the other option. <Q> I don't think you can make a 3x1 setup work. <S> In order to have the chain change gears, there needs to be a mechanism to take up the slack in the chain. <S> In a normal dual-derailer setup, the rear derailer does that. <S> You might be able to make it work with a chain tensioner, but I'm not sure if you can find one with enough range to do the job as well as a rear derailer. <S> Obviously you could do it with a rear derailer locked to the one gear, but that defeats the entire point. <S> A 1x8 or 1x9 would work fine, of course, since the only derailer is a rear derailer and it would handle the tension. <S> It's fairly common for "cruiser" and "town" bikes to have a 3-speed internally geared hub. <S> That would give you most of the extra durability of a singlespeed drivetrain and allow for a very thorough chain guard (no pant rolling needed). <S> Internally geared hubs often have a built in coaster brake, which would mean you'd only need a front brake. <S> Even better would be a belt-driven internally-geared-hub bike (no chain lube!), but that requires a frame (at least dropout) built for it and would definitely be more expensive. <A> inner hub gears are near zero maintenance, and as you don't need a thin chain, the external parts (chain, "cassette", etc) can be made fairly sturdy. <S> They also have a nice feature for town use: you can change gear while stopped at the lights. <S> No more anticipation or setting off in the wrong gear. <S> The Sturmey Archer 3 speeds are probably the most affordable to build a bike from; the ratio normally gives a good spread. <S> If you are hoping to fit this on drop bars, then you should be able to hook up a 3-speed front-shifter/brake unit to the SA hub. <S> I have an 1999 Sachs hub set up exactly like this; Shimano RSX road lever controlling shifting -it <S> just goes in the opposite direction from a front ring. <S> For 1x8 or 1x9 at the back, that's a pretty wide spread these days; you can go better than 1:1 at the bottom, at the expense of the upper gears: you'll need to get that front ring something everyone can agree on. <S> 8 speed is probably the best choice as it is easier to set up than 9 speed; the chains are wider and a bit stronger. <S> Even 9sp is easier than 10-11 for the same reason. <S> Going for a 1x8 would probably be a lower cost option as you can get rear freehub wheels for not much expense... <S> though once you add in the cost of wheel+cassette+derailleur there's less in it. <S> [ Update Aug 2018 ] <S> When those Sachs hubs start playing up you will discover that it's nearly impossible to get spare parts... <S> the only reason my bike is working again is the local bike shop found a replacement activation chain in one of their boxes of "old bike bits" <A> If there are no hills, do not bother with gears. <S> I have recently been cycling in the dunes quite a bit and see a lot of these (no gears) rental bikes. <S> While the dunes are not high, the roads through them tend to go up and down all the time. <S> Young adults are less likely to want gears for a relatively flat area than any other age group. <S> And students who can get a free or very cheap bike with no gears are more likely to take them, especially if the alternative is more expensive. <A> Singlespeed is cheap and should be generally sufficient for loaning to students. <S> Anything with dérailleurs is too frail and requires too much maintenance in this conditions. <S> Planetary gear is always nice, but for this kind of situation it should be purchased only if the locale is really hilly, you can find them cheap for some reason, or you have money to burn. <S> Also, if there is bicycle factory or a large repair shop nearby, you may try asking them for discounts or special offers. <A> I've known something like this: http://www.cycleexif.com/surly-dual-speed <S> but I don't know this will work for casual bikes. <S> I also agree with @reiheit, internal geared hub is much more nicer idea. <S> An example of this is bike rental system in Taipei ( http://www.taipeitimes.com/News/taiwan/archives/2012/12/10/2003549807 ). <S> I've been in Taipei for a while, and these bikes were awesome. <S> They had 5 speeds (If my memory is correct.). <S> Moreover, Internally geared hub is less prone to failures, and I think the bikes require less maintenance. <A> I would personally go for the 1x8 over the IGH for a couple reasons. <S> The first is initial cost. <S> 3 speed hub is going to cost more than a single 8 speed hub. <S> Also, it makes changing tires a lot easier. <S> Changing the tire on an internal hub can be quite daunting for somebody who's never done it before. <S> Internal hubs are more durable, but there are precautions you can take with deraileurs such as getting a guard shown below to ensure that they are protected if the person leans the bike down on it's side.
|
(But if you think it is needed, three gears (or up to 8 gears) inner hub gears work well.) If you look at the most popular rental bikes in the Netherlands you do not see any gears. Students who can use a free bike will be happy enough with a bike that actually works and does not break down just when they need it. Another option would be to go with an internally geared hub (IGH).
|
Finding better routes than bicycle apps suggest Nowadays there are many cycling apps like Strava, etc. One useful feature of them is giving the shortest or lowest altitude change route between point A and B. Although they have that lowest altitude change, some of these routes are definitely not easy to climb up. For example, from my house to shopping mall, there are 2 routes, one is suggested by Strava and the other one is mine as well as any citizen of my town would suggest. Route 1. Climb %8 hill until reach the shopping mall. Route 2. Climb %15 very short hill, then ride downhill a parallel way to Route 1, then climb very short %15 hill and you reach your destination. Definitely it is easier to ride Route 2 and also it does not need so much physical condition since it does not always climbs. My main point in here is that it seems easier to climb a high slope for a short period of time and drive downwards to recover. My question : is there any apps that can create routes like Route 2? <Q> This is an impossible question for the mapping sites to answer. <S> They come up with heuristics about what makes a good route, that will do a pretty good job, but there is fine detail they do not and cannot know. <S> For example, Your route 2 is the easiest on paper, but what if it poorly sealed with course chip and has lots of rubbish and stones in the shoulder. <S> Route 1 would be better. <S> What if route 2, getting onto the top of the ridge exposed you to a prevailing head wind that route 1 was sheltered from - <S> in this case the best route changes daily (Where I live, hourly). <S> Add to this, a good route is subjective - as already suggested by @bibz guys out for training rides have different definition of good to a commuter. <S> As a MTBer, I have a different definition of good to a roadie, as I have much lower gearing <S> I can climb steep hills roadies want to avoid, I careless about gravel roads, road works or poorly maintained roads than roadies. <S> They tend to want to go faster (and further) then I do. <S> I am a strong hill climber, and will take a hilly route over a flat route any day, there are many who hate hills and a much stronger than me on the flat. <S> (TBH The vast majority who are stronger than me everywhere). <S> In the end technology cannot make you decisions for you, all it can do is make suggestions based on the data it has. <S> Ask around locals for better advise, but in the end you have to actually ride the routes to work out which is best for you. <A> Strava has the option of using "Popularity" to create a route. <S> This means that if more people use Route 2, it should make you go that way. <S> The problem if that if a lot of people are training using Route 1 it might skew the resulting route the other way. <S> There is also the option of manually creating the route using Strava or RideWithGPS or other mapping sites, but that would mean that you have previously know which one is the best. <A> Just stick to the most frequented roads or paths <S> and you should be okay. <A> Brouter allows creation of custom profiles, with possibility of preference rather shorter, even if steeper climbing. <S> Some of such profiles are publicly available
|
Usually I start by checking where other people are going by when I plan my trips, then I can do adjustments based on riding it or by talking to the locals. Expanding upon a previous answer, you can use Strava's Heatmap feature. Route 1 has been recently sealed with smooth, fast hot top and has a wide clean shoulder.
|
Bicycle maintenance notes, technical book: do you have one? Well, I drive a car and I have a technical book (maintenance) and automatically I want to do the same for my newly bought bicycle. I would love to track repairs, maintenance schedules, changed / added parts, at the same time stats (weight, part durability per km), mileage and stuff like that... Unfortunately, when I bought my bike I did not receive any of such kind. So, my questions would be: Do you have 'technical maintenance book'? Maybe you have a digital template? Maybe I could buy one somewhere? Or maybe there is a better way you could suggest :) I believe that good bike owners should properly take care of their bikes thus providing better value on resale and future maintenance. <Q> Maintenance on a bike is much less than maintenance on a car. <S> It is a much, much simpler machine with far fewer parts. <S> As such there isn't such a thing as a maintenance schedule or service book. <S> That said, there are a few things you should do; Tyres Visual inspection and pressure check once per week. <S> Chain <S> The chain needs to be cleaned and lubricated. <S> The frequency will depend on how much and how long you ride, as well as the conditions. <S> I ride on average 100-150 miles a week and do mine roughly once per fortnight. <S> In the winter when it rains a lot and there is salt spread on the road it tends to be weekly. <S> You should also check your chain for wear and stretching occasionally. <S> You can buy a tool to measure the stretch. <S> A decent chain will last anything from 5000-10000 miles or less if it isn't looked after. <S> You might also want to replace your cassette when you replace your chain, but this can be expensive. <S> Again, if looked after a cassette should last 10000 miles easily. <S> Brakes Check and adjust every so often, maybe once per month. <S> Brake cables stretch and the blocks wear out and need replacing. <S> Gears Once set up correctly gear mechanisms generally don't require much maintenance. <S> On a new bike you may need to adjust after a month or so due to cable stretch. <S> Other components such as head sets, bottom brackets, wheel hubs etc are generally very long lasting and shouldn't require regular maintenance. <S> In fact these mostly now come as unserviceable sealed units. <A> Buy a Park Tool Big Blue Book of Bicycle Repair or one of the Zinn and the Art of Road Bike Maintenance (or Mountain Bike Maintenance ) <S> and you'll have some pretty comprehensive guides on how to maintain, fix, or replace just about anything on your bike. <S> Specialty tools may apply for various tasks though. <S> Online resources are good as well. <S> See Sheldon Brown 's website for lots of great tips, with lots of commentary. <S> Some info may not be as current as other resources though. <A> Bicycle maintenance is more generic than car maintenance due to design. <S> Bikes don't often have any custom parts besides the frame. <S> All the rest are usually off the self components from different vendors. <S> So, there is not much point to have maintenance schedule for a particular bike. <S> Besides, bikes usually don't come equipped by bike computers by default <S> so it's not given that users can reliably keep track how long distance the bike has been ridden. <S> To keep good care of your bike, I recommend: <S> Learn how to inspect your bike and keep it tuned up. <S> This is fairly simple. <S> Mostly you just need to keep nuts tight and proper places lubricated and you're good to go. <S> Take your bike to shop for proper check up at least once every year or riding season. <S> Doing it before any longer bike trip is also good policy. <S> Store your bicycle properly. <S> Keeping bike indoors over winter does a lot for lifetime of the bike. <S> That's it. <S> Learning to do basic repairs is pretty easy, can save a lot of money down the line and is pretty much required if you intend to go touring or do more serious riding. <A> I have a "Bicycle Diary", just a plain notebook where I keep a log with every maintenance task done (parts changed, chain lubing, greasing, ...), rides (where, when, how long, ...) and general notes. <S> I also made a chart with entries for each component (chain, cassette, pads, ...) <S> and the odometer lecture when I changed it (so I can know when a replacement is due).
|
So I would recommend that you buy a generic book about bicycle maintenance and a basic tool set and prepare to get you hands dirty every now and then. Most bikes don't really come with much of a guide or instructions.
|
What are the absolute essentials a cyclist should own? Context:My bike shop includes free servicing as a standard with a new bike. I don't need such thing and live too far away. In lieu of waiver I can get €100 of stuff from the shop. Best bike problem ever: I need to decide what to get for free form the bike shop... Can anyone advise on what they would consider to be absolute essentials as a road/touring cyclist? <Q> This is what I tell everyone to get first when they get a new bike: Seatbag, to hold the following: Spare tube (maybe two) Small multitool <S> Mini-pump or CO2 inflator Tire patch kit <S> 2x tire levers <S> That assumes you have bidons and cages. <S> Those six things should get you by for many miles and should get you out of any trailside emergencies. <S> As with anything though, make sure you know how to use them when the need arises. <S> For your own personal bike shop, I'd recommend a good floor pump with a pressure gauge, some high quality chain lube, and a maintenance book for DIY repairs. <S> Nothing hurts worse then getting hit by a motorist that "didn't see you" at an intersection. <A> Bicycle Helmet Suitable clothing and shoes <S> Cellphone <S> Whatever else you "need" depends on your mechanical abilities and how independent you wish to be. <A> I would go for a good floor pump, as I find it can be extremely important in preventing flats. <S> One big problem I see is underinflated tires. <S> This can cause flats and other problems like rim damage. <S> If you plan on leaving your bike anywhere except your garage, then a good bike lock is also quite essential. <S> If you have those things, then I would probably opt for replacing the stock tires. <S> Often the stock tires on bikes aren't great, and you would be able to get a pretty good set of tires for that amount of money. <S> Could easily save you from lots of frustration down the road. <A> (I don`t have a definitive answer) . <S> I would concentrate on what is most frustrating when it fails when riding a bike: <S> Tire and wheels maintenance: Tire levers. <S> Good air pump. <S> Good tube patch kit. <S> Replacement tubes and tires. <S> A set of hex wrenches (check Imperial vs. Metric) <S> After that, you can add whatever you feel will help you maintain your bike (specific wrenches, lubrication and grease,...) <S> Insipired by: http://www.bikeradar.com/gear/article/home-wrench-building-a-cycling-tool-kit-from-scratch-43564/ <S> http://www.bicycling.com/maintenance/bicycle-tools/16-essential-bike-tools <A> If you already have the usual tools and clothing you can always need more of the typical wear parts: <S> Tires, tubes, chains, brake pads, chain oil, cables, pants … <S> Otherwise I’d start with a proper stand pump, mini pump (for on the bike), tubes, chain tool, hex keys, lock, bottles, helmet … <S> Clothing is of course essential but hard to guess the right size for ordering. <A> <A> My 20 mile work commute requires panniers, cold and wet weather gear for the winter, lights for early morning and late evenings along with the common small items: 1. <S> Two spare tubes2. <S> Patch kit3. <S> Bike-specific multi-tool4. <S> Frame-fit pump5. <S> Emergency identification6. <S> Water bottle with water Regular ID, insurance info, cash, phone, clothing, keys, safety equipment, bike lock, shoes to fit my clipless pedals, and other items taken for granted are assumed to be on the list. <S> Ziplock bags for anything that can't get wet may also be added to the list. <S> I choose to use a GPS enabled cycling computer for courses and routing. <S> On my tour from Maine to Florida, I carried significantly more. <S> For closer to home touring, one can go a long way with little more than a patch kit and a pump.
|
Also a helmet should be entirely recommended as a required purchase, and probably front and rear lights. A good floor pump will make it not so much of a chore to ensure your tires are always properly topped up. If it's a quality bike, it will attract professional bike (part) thieves – which are everywhere, like bacteria – and you should invest in a quality U-lock and a set of good anti-theft skewers for the wheels and seat post. Depends on the type of tour you are doing.
|
Commuting on flat terrain/handle bar For my new job I'll have to commute about 10 - 20km (6 - 12mi) each day (one trip) in flat terrain. Right now, I'm commuting 6km/4mi each day, with an elevation gain of 160m uphill to work. I'm riding a hybrid bicycle with a gear hub (only one gear lever) and a straight handle bar. I assume that for my new route, a more aerodynamic position would be nice and I'm pondering about a better handlebar choice -- drop handlebars or tri bars as addition to my straight handlebar? Is it just a matter of personal preference, or are there general pros and cons? The route will be mostly on a seperate bike lane next to a road with little traffic. <Q> For that reason alone I would advice a drop bar or butterfly bar. <S> It'll prevent all kind of small complaints about wrists, shoulders and back. <S> Getting in better shape because of the extra daily exercise, you'll gradually feel more comfortable in a more sportive (aerodynamic) position. <A> I'd start off just riding your bike and noticing what you like (and don't like about your position). <S> Mostly I'd worry about the bars being too low and not having enough options (get low to get out of the wind, sit up straight when your back or neck needs a break, and on and on...). <S> The important thing is that you're comfortable – and as long as the bike comes reasonably close to fitting you you'll be able to make adjustments that will make it very comfortable. <S> But back to your question. <S> There are three general bar options: <S> Flat bars like you've got and their variants (mustache bars, albatross bars, hershey bars, all sorts of fun to be had here). <S> If you don't ride hard and like an upright posture, this would be where to start looking if you need more variety in your position. <S> Trekking or butterfly bars, these are basically flat bars with a larger range of positions. <S> The forward position is a way to "drop down" a bit to avoid wind drag. <S> Dropped or road bars. <S> These are my favorites. <S> I like the range of positions and I'm used to them. <S> But, really big but, they are close to useless if you can't get them up high enough. <S> I run mine with the top of the bars about level with my seat, so riding on the tops of the bars <S> my posture is pretty much the same as it would be with flat bars. <S> However, I can also lean a bit forward, riding with my hands on the hoods of the brake levers, or if there's a headwind <S> or I'm trying to look cool and fast <S> I can drop down onto the bottom of the bars. <S> But most of the time I ride on the top of the bars or on the hoods. <S> So I think you don't need to be in any rush to buy new bars. <S> One last thing, it isn't the length of the ride that dictates when aerodynamics comes into play, it's more the speed (either your speed or the speed of a headwind). <S> At 15-20 kph I don't feel like I'm working too hard against the wind, but up around 25 kph <S> I definitely notice it (but not enough to make this old man want to spend much time of the drops), up past 30 kph the drops are looking very attractive. <A> You didn't tell what hybrid bike you have <S> but I assume the effective top tube on your bike is longer than ones on road bikes. <S> Another consideration is that drop bars have additional reach forward (70-80mm). <S> Although I've never tried this). <S> Additionally, I assume you want to be faster. <S> have you considered to purchase slicker/narrower tires? <S> This solution might be less hassle and way cheaper. <S> Being in aero position is nice but tire selection is much bigger factor to get faster, IMO. <A> You can already try to get into a more aerodynamic position with your straight handlebar. <S> On a road bike the drops are mostly used for descents, normaly one uses the “hoods” or the tops which aren’t all that “aggressive” or overly aerodynamic. <S> See also http://lovelybike.blogspot.co.at/2012/06/drop-bar-hand-positions-introduction.html for all the positions. <S> The internal gear hub will be a problem for drop bars since there are no shifters available and you’d have to use one of the makeshift solutions. <S> You could try adding time trial bar clips, but it can be hard to find a good position on a normal bicycle with them. <S> Some pictures of your bicycle and seating position would help. <S> You shouldn’t underestimate the impact of floppy clothing either.
|
Drop bars are possible, but you need to measure the effective top tube of your frame and the "reach" of a new drop bar you want to purchase. When spending more time on your bike, it's good to be able to vary your position. A shorter straight handlebar can be quite aerodynamic. There's high a possibility that you'll need a shorter stem (< 100 mm), however, the handling might be funny ( It’s not only a matter of handlebar type.
|
Standing vs. high rpm for acceleration I've been working on my cadence for several months now, and I feel like I've gotten to the point where I'm more comfortable using high cadence instead of standing up when I want to accelerate hard. At stoplights if I'm really gonna accelerate hard, I'll start in first gear and shift up when I get to 140-150 rpm. I stay seated the whole time. I feel like I'm faster this way than I am standing up, but I'm not sure. Until recently, I've always assumed that standing up in a higher gear was the best way to put on speed fast. Can someone provide data or logic that points one way or the other? <Q> The only way to be sure is to measure. <S> You can use an app such as Strava during the ride, then look at it's analysis later. <S> It will show you how fast you were going at each point, and also gives an approximation of your power output. <S> We don't know what algorithm or assumptions <S> it uses to calculate the power, but since it uses just one algorithm you can compare results for seated and standing sprints. <S> Strava doesn't know what the wind speed is, nor does it know what your frontal area is (which changes when you stand), so the power values are not correct in an absolute sense. <S> The speed measurements are more useful. <S> I would expect that you'll be producing most power at the higher end of your cadence range, 120-140 rpm. <S> In my experience a standing sprint is good for a short burst, rather than the extended acceleration you describe. <S> Using the higher cadence will be better for your knees over time. <A> I sometimes see the standing grinders but by the first downstroke of their crank arm, I am already gaining much more acceleration. <S> The grinders are also wobbling all over the place because their centre of mass is much higher and the bike is harder to keep in a straight line. <S> I commute on a Trek FX 7.2 and have found my most effective starting gear is using the middle front chain ring (the 38 of 48/38/28) and the largest rear sprocket (the 32 of 11-32, 8 speed). <S> Once I am spinning at a cadence which is around 80% of my physical limit, I then momentarily relieve the tension in the chain and change one gear (change up rear sprocket). <S> It takes a bit of practise to get this right <S> but it avoids the gears clunking while you shift. <S> Another benefit of starting in the 38 front chain ring is that I can accelerate to beyond my cruising speed in this chain ring. <S> If I were to start in the 28 chain ring, then I would need to lose some acceleration while making the shift to the 38. <S> A shift between front chain rings is much more time-consuming between a shift between rear sprockets. <S> I also make sure that my saddle height is correct and on the limit of being too high. <S> When I am at the lights, I need to fully extent my leg for my toes to reach the road. <S> While I do this, I keep my other foot on the pedal in the ready-position. <S> As soon as the lights change, I apply power and my extended leg has to 'catch' the spinning crank arm. <A> The answer is probably the combination of standing up and high cadence. <S> I assume that when you say acceleration you mean hard and short burst of effort. <S> The maximum power in that short period of time will be produced by the fast twitch muscle fibres type, (i.e. when you stand up, low cadence). <S> This type of fibres work anaerobically so you can only sustain it for very short time. <S> If you need to accelerate longer than what the anaerobic system can provide <S> then you will need to switch to aerobic using the slow twitch muscle, i.e. high cadence. <S> That's why sprinters have huge thighs, they go to gym for resistance training. <S> There's a table with muscle characteristics here: <S> Fiber typing <A> Get a power meter and see what output you are getting at various rpm / loads. <S> There is a big difference of 120rpm at 200w or 600w. <S> This relationship will most likely not be linear. <S> 150 rpm seems much too high, but everyone is different. <S> I personally find great power at 105-120. <A> As already stated, measure. <S> But maybe not the whole commute, because it introduces confound variable like traffic light timing, other road users, hot or rainy weather. <S> I would rather get a friend with a stopwatch and spend a couple of hours on an empty parking lot (if that simulates your most common riding conditions, maybe a forest clearing or unoccupied forest track else). <S> Have markers for where you start from and <S> about 30 meters later the "finish line". <S> Do factor in the final gear you end up in. <S> Id est <S> if your steady-state gear is X, after this sprint you are going to need to spend time to get to that. <S> Do factor in that high forces <S> wear your knees out. <S> In the extreme case, you can stand up and pull the handlebars towards you, allowing crazy acceleration. <S> And knee wear. <S> Do make 5-10 measurements for every type of riding so that you can compute mean and variance. <S> And get back to us. <S> This experiment sound fascinating!
|
Through personal experience, I have found that the higher cadence method will always get me ahead of the group of commuters at the lights. I think you will need to experiment with which gear you start in while accelerating in the saddle. Timing yourself or using HR can be a measure as well, but power is the only way to know for sure. Even if you measure and find that high cadence is faster, it could also probably mean that you haven't train your anaerobic system enough to get the expected results. With a lower saddle, it will be near impossible for your legs to transfer power with a high cadence.
|
Can you inflate a completely flat tire? I haven't used my bike for almost a year and I need to start riding it again, but it appears I have a flat tire. I don't think there's something wrong with the tube cause I haven't used it for a pretty long time. It just won't inflate. The tire has a Schrader Valve. I use a pretty old pump so maybe that's the case? I'm not really sure.. So is there any way I could inflate it again without getting a new tube or tire? <Q> You can easily inflate a completely flat tire (provided the tube is still good). <S> With a presta valve, you can use your mouth for this (well, on a clean tube, since the valve stem isn't spring loaded), but with a schrader valve you have to use a pump. <S> If it still won't inflate, check the tire and tube for damage and replace accordingly. <A> Make sure the valve isn't stuck. <S> If it's been sitting that long it probably is. <S> Look at the valve <S> and you'll see a pin in the middle. <S> This pin needs to be depressed for the valve to open and allow air into the tube. <S> Press down on it with a ball point pen, screwdriver tip or similar object to unstick it. <S> Then follow the advice above about holding the tube in place while you attach the pump. <A> I had a similar problem and what worked for me was soaking the valve in white vinegar as you would a shower head for half an hr and then gently pushing the middle bit with an old ikea small allen key. <S> worked perfectly. <S> ps i used a tissue soaked the tissue (cotton balls are better) in white vinegar, place them on the valve wrap in foil around tire <S> and I let it sit for about an hr or 2)
|
Usually, when a tire is completely flat, you have to press the back of the tire so that the valve doesn't recess into the tire so your pump can be attached properly to it.
|
Is there a standard equivalent for effort between distance and elevation? I'm starting to keep track of how far I ride on paper and while it's nice to have the data, I'd like to know how different rides stack up. I have one path I like to take which is really flat and goes about 30 miles out (I usually only do 10 and then turn around), but I've found this ride is much easier for me than the other route I take which nets me about 12 miles and about 500 feet in elevation. I saw on another SE that they calculate 500 feet elevation gain into one mile, but this doesn't seem that accurate for a bike. So, what I want to know is if there is a standard calculation for "effort" or distance between distance and elevation gain, given perhaps average speed or any other relevant factors. <Q> If you really want to measure how much effort you're putting in, you should look into getting a power meter. <S> It measures the actual wattage you output, and can therefore be used to calculate total energy output. <S> However, they are quite expensive. <S> This ends up being much cheaper than a power meter, but is less accurate. <S> These are the preferred methods if you a really want to track how hard you are training. <S> This is because many things can effect how much effort it takes to cycle such as hills (like you mentioned), but also wind, your body position, and the road surface itself. <A> The short answer is no, there is no standard equivalent for effort between distance and elevation. <S> Of course, as others have mentioned, they are connected by the amount of effort you put in. <S> So riding 10% faster takes 20% to 30% more effort. <S> This is mostly down to wind resistance, but rolling resistance plays a part too. <S> On a hill, your (well, at least my) speed is lower. <S> Lets say you're climbing at 10kph (6mph). <S> So the wind resistance is way lower (less than 1/6th) than the resistance you would have at 25kph (15.6mph). <S> The main work (5/6 of the effort if you're producing the same power) <S> you're doing is levering yourself up the hill. <S> If you go 10% faster then the wind resistance still rises by 20% or so, but the effort of getting up the hill rises linearly. <S> So the point is, it's complicated. <S> That's why there's no equivalence. <S> This is why, if you look at Strava or other tracking apps, they distinguish distance and elevation. <S> They also distinguish time in the saddle, because measures something else: endurance. <S> For a real example, take a couple of my own rides. <S> Today I rode an out and back course over 28 km (17.5 mi) with 650 m (2132 ft) of climbing. <S> It's an undulating course averaging about 2.3% I averaged 25.3 kph (15.8 mph), similar to your pace. <S> While not flat, it is compared to the next ride ... <S> In the summer (it's winter here now) <S> I climbed a hill. <S> It's 1100 m (3600 ft) of solid climbing in 17 km (10.6 mi). <S> It averages 6%, with pitches up to 24%. <S> It took me 1 hour 45 minutes, for an average speed of only 9.7 kph (about 6 mph)! <S> There are two things about these rides. <S> They show that I'm just a cyclist of modest abilities, so such comparisons should be relevant to you and many others. <S> They also show the effect of continuous climbing, the effect of steeper hills, and the effect of longer duration, all tangled together. <S> It's complicated. <A> It really depends on speed. <S> If you go slow (and there is no headwind) <S> then riding on the flat is almost effortless <S> (rolling friction is a very small factor with properly-inflated road tires). <S> What slows you on the flat is wind resistance, and the faster you go the more wind resistance you face. <S> On the other hand, climbing a hill of a given height consumes a fixed amount of energy regardless of how fast you do it (once you factor out wind resistance), and, in theory, regardless of how steep the climb is (though of course once the hill gets too steep to climb "theory" falls apart). <S> You can probably come up with a way to convert a given % climb rate into an equivalent headwind for you and your bike, but there's no way to convert % climb into level miles with any degree of meaningfulness. <S> At best you can come up with a conversion factor that assumes a given speed or energy output. <S> And this would obviously be different for every rider. <A> It depends on other factors as well. <S> A big one is speed. <S> When you climb a hill, there is a minimum energy expenditure to get up the hill. <S> On the flat, there is almost no minimum, but riding 10 mph is much easier than 15 mph (or whatever range of speeds is suitable for you). <S> Elevation gain can be measured in various ways as well. <S> If you use Strava or MapMyRide to tell you that you have gained 500 feet, that is much less than looking on a map and finding you got 500 feet above where you started. <S> The apps add up all the little ups along the way, so may report 1500 feet of climb when your altitude is just up 500 feet. <S> You have to get used to it. <A> If you want to use your own figures from strava or some other program you can easily get get a feeling for the relative effort between biking a certain distance on the flat and on a grade. <S> Use this calculator.... <S> http://bikecalculator.com/ <S> For example I have a 2 mile hill at 5% which my best average speed is 9.3 mph. <S> Entering the data gives me a calorie total of 185 calories. <S> If I bike that same distance at a 0% grade at 20mph it gives me 68 calories. <S> All of which feels about right to me, although if you asked I would have guessed that biking the 5% is easily 3 times harder. <S> For fun to see how fast I would have to go on the flat to equal the 185 calories at 5% <S> I got 36mph, something I cant do for 1 second much less 2 miles.
|
The other option is to get a heart rate monitor along with cadence and speed meters which together can give you a reasonable estimate of how much energy you used. If you climb hills fast, you will get tired quickly. But as you ride faster on the flat, the power required to drive you along rises as the square (some say the cube) of your speed.
|
Foot pain with cleated shoes I have cleated shoes. My feet do a lot of work floor miles and get I pain in ball of my foot. I feel like the cleat is pushing on the ball of my foot. I was considering changing the shoe liner; would this help or not? I have N.W foot wear, they are at least 6 month old. <Q> Usually shoes for walking/running and cycling <S> shoes are constructed quite differently: shoes you walk on are usually far less rigid, most have a much softer sole to absorb shocks/bumps, and of course do not have cleats. <S> As this is ergonomics and people are quite different, there is probably no general answer: I find walking in SPD Trecking shoes uncomfortable, but not enough that I would not use them every day. <S> For your specific problem, I guess changing liners could help. <S> However you'd need very stiff liners that actually distribute unevenness. <S> I have not yet seen those. <S> Assuming you have static workplace: maybe you could arrange having a second pair of shoes specifically for walking there? <A> Keep some regular shoes at work for this purpose. <S> If you are talking about during bike use, then I would consider getting a bike shoe with a more rigid base. <S> Ones with carbon soles (if you can afford them) solved a problem I was having with tenderness at the ball of my foot. <S> Having the right bike shoes can be well worth the investment of about $150. <S> Also, I have gravitated toward mountain bike shoes with SPD pedals on all my bikes to simplify the situation and to make it easier for walking around. <A> My Specialized Cadets are OK for a full day of walking and sitting, though I don't make a habit of it, instead I keep shoes under my desk. <S> I'm also used to wearing hiking boots with stiff soles <S> so that makes them feel less unfamiliar. <S> The discussion under my related question may also be of interest. <S> You should probably link to the exact shoes you've got -- <S> at the moment it's not even clear what type of cleats you mean. <S> If they're generously sized (which they shouldn't be)
|
you may have room for a layer of something thin-but-stiff under the original liner or some sort of insole. It wasn't clear to me about "work floor miles", but you shouldn't be doing any general walking around in bike shoes for any significant distances.
|
My Bike doesn't seem to fit itself I have a project bike. I made it myself from bits recycled. It is currently a single speed, although I'm thinking of adding gears to turn it into a bit of a commuter/excercise bike. Before I do that, I really need to sort out the fit. It doesn't seem to fit me, or even itself very well. Bike dimensions - 51cm seattube, 50cm top tube, chain stay 41cm. tires are 700x32. The problems: The bike has a seat tube length of 51cm which seems right for me at 5'6. When i sit on it my leg is straight at the bottom of the stroke, However there is virtually no standover room. the bike seems pretty cramped horizontally, that is the handlebars seem too close to the seat. in fact i'm not sure if the top tube is long enough. The front wheel, despite being the right size to line up with the brake, seems to be way to close to the downtube, and as a result clips my toes sometimes when I'm pedaling. Does this bike even fit itself? both wheels are pretty tight through the brake. That's probably because of the chunky tires. What have I done wrong? How can i get the bike to feel a bit less cramped? <Q> 622mm wheels are too large to fit comfortably in a 51cm frame. <S> This bike has been made the other way around and that is why it looks and feels strange. <S> With saddle as low as shown in picture, the frame is too high for you. <S> With horizontal top tube, there should usually be about hand's width of seatpost showing. <S> Longer handlebar stem or less swept back <S> handlebars will help. <S> This is a problem with all small frames with large wheels. <S> Is the fork the original one? <S> Some older bikes came with steep steering angles and very high fork offsets. <S> The offset eliminates some of the problem with toe overlap but makes steering twitchy at high speeds. <S> 32mm tires are the absolute maximum size to fit inside short reach brakes. <S> Normally the kind of brake is used with 23mm to 25mm tires. <S> Edit: @Will's comment led me to the idea that this bike could have been a 650B or at least converted into one. <S> That would reduce the standover height and allow wider tires and also explain the strange-looking angles. <S> Smaller wheels would lower the bottom bracket, so saddle would still look too low. <A> Adding to the answer by @mattnz ... <S> The steep headtube angle is supposed to be matched with forks that have more forward curve. <S> And it should have drop bars. <S> Here is another Parleigh, built as a fixie (from here ): <S> Notice the seat height, and the reach to the bars. <A> The bike was built as a racer and it looks you are trying to make it into <S> a hybrid/Commuter and get a more relaxed riding position. <S> This wont work as the geometry is wrong for that. <S> Have you tried with the seat more horizontal. <S> As it is, it will push you forward. <S> Its also as far forward as it will go <S> - slide if back on its rails. <S> At the same time raise the seat height and/or lower the handlebars - normally a road bike the seat is higher than the bars. <S> If this does not work drop bars might help as would a longer stem. <A> Either get one with a shorter seat tube, or get a "compact" design with a sloping top tube. <S> You can just stop reading here, but I'll answer your other points just because. <S> The fork you have is not the one that originally came with the frame, is it? <S> Toe overlap is something you can learn to live with, though. <S> As long as the tires aren't rubbing, there's no problem. <S> If there's very little clearance, you just have to pay close attention to it, and make sure your wheels are true. <S> Or get skinnier tires.
|
Usually sizes this small are made to compensate with very steep seat tube angle to let the rear wheel forward and very shallow steering angle to avoid toes clipping front wheel. If there's little stand-over space, then the frame doesn't fit you, and there's nothing you can do except get a new frame. The saddle should be roughly horizontal. You can move the seat back, or get a longer stem, or get handlebars that put your hands further forward. The geometry of this frame looks odd. This looks to me like an old frame to me. The original fork probably had a higher rake, which would put the wheel further forward.
|
Toe overlap on mountain bike How common is toe overlap on 29" wheel bikes? Also, is there a way to fix the overlap by say replacing the shocks for some with more travel? Lastly, is toe overlap a major issue on a mountain bike? <Q> I know when I am not using cleats, I sometimes get a bit of toe strike, less so now, but initially it was happening regularly. <S> Its not a major issue, you get used to having to keep your feet back (where they should be for efficient riding) <S> Clip less pedals solve the problem completely. <S> There is a reason the industry quickly moved to 650b. <S> One take is one size does not fit all as the failed 29 experiment shows. <S> The other (cynical one) is the industry needed a reason to sell more bikes, so they came up with 29er as the new "must have" for a couple of seasons then introduced the 650b and said "this one is much better again", knowing all along 650b was a better "one size for all" size..... <A> I don't know how common it is. <S> I can tell you that it's not as big a problem as you would expect. <S> Toe overlap only comes into play when you're making very sharp turns at low speed. <S> Hitting your toe on the front tire would be dangerous at high speed - but at low speed, it's just annoying. <S> And it doesn't even happen that often. <A> I have a 46cm gravel bike with 170mm crank arms (it's a Surly Cross Check, it's approximately equivalent to a 50cm road bike ). <S> Although it isn't a MTB, it's still a 29er <S> (700c = 29er with narrower tires). <S> Indeed, toe overlaps are issues for me, although they are more like annoyance. <S> Toe overlaps mostly happen when I stop at a red light, or sudden strong braking (almost completely stop) with a sharp turn. <S> However, when I ride the bike in trails with twisty turns, at a reasonable speed, toe overlaps have never occurred. <S> At first, it's quite annoying <S> but it's not the end of the world. <S> After a while, I'm used to it <S> and I don't plan to modify my bike. <S> edit:Recently I've been trying a lot of things on my bike, here's what I can tell from my experience: <S> Go for thinner tires, I used 700x40 tires and toe overlaps happened more often. <S> Afterwards, switching to 700x35 tires reduces the occurrence of the problem. <S> Depending of the tires, 5mm tire width difference is very noticeable, since the diameter of the fully inflated tires can be significantly reduced, so the distance between the pedal axle to the tire surface is increased. <S> Use clipless pedals. <S> This might not help depending the pedalling habit while using platform pedals. <S> When I used platform pedals, my foot position was already around the ball of the foot, so after switching to clipless I do not feel any difference. <S> However, clipless pedals give some kind of predictability since my foot position does not change so I can guess/predict when the toe overlaps will likely to occur <S> and I rotate the pedals backward to avoid them.
|
I think toe overlaps don't affect the riding performance. Best not to try and 'fix' the overlap - the bike geometry will be negatively affected unless extreme care is taken. It is known some people moving to 29er's have issues with tow overlap, especially on small frames.
|
Swap MTB parts to road bike I have changed my tires to road and crank set to 48 teeth. The question is with all my current parts is there a way I can buy a road bike frame and transfer everything on to the road bike frame? My MTB is running disk brakes, not a V-brakes. <Q> What's the wheel size? <S> If it's 700c, then you can get disc road/CX/gravel frame. <S> Do mind type of bottom bracket, hub widths and seatpost diameter, though. <S> You can fit MTB shifters and brake levers to a drop bar, but that would look funky, so probably flat bar only. <S> For proper fit, stem might require replacement too. <A> Its almost always more cost effective to sell the existing bike and use the funds to buy a (used) bike you want. <S> Its worth doing it from the perspective of learning about bikes, owning a unique piece of art/engineering "franken bike" or just a cool way to kill some spare time. <S> Doing it because you want a road bike and only have <S> a MTB is the wrong reason. <S> Little things like wrong length cables and chains, incompatibly betwen bottom brackets (chain line problems) can quickly add up to a lot of $$$. <A> There is a certain degree of compatibility, but usually it comes with a big compromise, such as having to use a flat handlebar (for your MTB shifters and brakes), smaller diameter wheels (road is 28", your MTB is likely 26"), lower gearing (pedaling on road is easier <S> so gears are higher) or bigger than usual tires (because of your wide MTB rims). <S> By the time you found a road frame that supports discs and bought all the non inter-changeable components you will see it's not worth it. <S> If you are really really interested in doing this you can post a few pictures of your current MTB and the kind of bike you are looking for and we can help you component by component, but trust me, you will end up getting a road bike.
|
If you want drop bars you need road shifters that are not compatible with MTB derailleurs meaning some big ticket items.
|
Butt pain during riding I am an recreational cyclists and I like training, but on my last training ride I developed pain in my right buttock, I also got a bit of swelling, the area is on the back of the thigh just under my right buttock. My background as a cyclist: I ride for several years mostly in the summer season, this season I have around 160 hours over the last 4 months and around 5000 km. I must mention that in the same area I had saddle sores which now are solved because I am lubing the area before each ride with some sort of sports cream. I suspect something is off with my riding position since it puts too much pressure on particular area, but it is strange as on the previous training ride I haven't felt any problem. I would like to avoid fiddling around with my saddle position as I haven't changed in the last 2 years at all. Any idea what could cause this and how to manage it? <Q> I would check your saddle. <S> I had the same issue and it was solved with a new saddle. <A> From here : If You Have: Numbness/pain from saddle <S> Then: Position or saddle needs to be changed <S> Some causes: Handlebar too low, causing you to rotate pelvis forward to reach bar. <S> Saddle tilted too far up or down. <S> Saddle too far back, <S> so you're riding on the nose. <S> Your saddle doesn't fit your anatomy Possible fixes: <S> Raise handlebar with spacers. <S> Level your seat. <S> Check saddle setback. <S> Try a different saddle—your weight should be supported on your sit bones, not the soft tissue <S> These links might also help you, here and here . <A> If your saddle has been the same and nothing really changed, maybe it was something you did prior to that bike training on that day or before. <S> Did you warm up as usual prior the training? <S> Did you drink enough water prior the training? <S> Change of diet might have something to do with it. <S> Change of clothing? <S> It looks like just a pull on your butt muscle. <S> I suggest you rest a few days and observe.
|
If working with saddle/stem position does not help, or if even after finding your most comfortable position you're not still ok, I think you are on the market for a new saddle. They can and do wear out and collapse. Play with your ergonomics on the bike should make a big difference.
|
Unable to loosen IXOW Wheelguard Gravity nut I have a Canyon Commuter 7.0 which uses IXOW Wheelguard Gravity skewers and nut. I want to take my front wheel off but am unable to loosen the nut on the front skewer. The standard procedure is to flip the bike upside down and then loosen the nut. This does not work. The instructions state that if the nut cannot be loosened, it should be tightened a little before loosening as doing this should release the locking mechanism. This approach worked for the nut on the seatpost clamp (which uses the same type of nut), but has not worked for the front wheel. The recommended tightness for the front wheel nut is 5-7Nm. I've already increased it to 8Nm when tightening in an attempt to loosen - it slipped at this point, so I don't want to try much more force in case I damage it. I've tried flipping the bike upside down a few times, to no avail. What else can I do to try and loosen the nut? <Q> Exact same problem here. <S> Same bike. <S> I got it off finally by just turning really really hard using a non-torque wrench. <S> Make sure it's rotated so that the two dots are UP (12 o'clock). <S> If installed correctly the lock should be at 12 o'clock when wheels are on the ground. <S> So if you installed it in the wrong orientation (i.e. lock at 2 o'clock or 9 o'clock etc), then turning it upside down will not be the correct position. <S> So rotate the bicycle around until the two dots are at 12 o'clock. <S> You can see from my photo <S> it seems that when tried to loosen it, the tab on the black washer that is suppose to be in the fork dropout rolled into the plastic dropout insert which was causing it to bind. <S> Going to write Canyon about this to see how I can get it repaired. <S> Same thing happen to you? <S> Explained in the instructions from IXOW--packaged separately from the urban manual. <A> I had the same problem because I did not install the lock in the right orientation (lock icon needs to point upwards). <S> When trying to unlock I damaged the plastic dropout insert (see photo in answer of maxhodges). <S> After I discovered the wrong installation (thanks to answer of maxhodges) I was still not able to loosen the bolt because the tab on the washer simply slipped through the damaged dropout. <S> Loosening the bolt was then easy. <A> i did the same mistake at first. <S> and I tried to reach Canyon Service Hotline both by livechat and telefone. <S> unfortunately neither of them worked. <S> back to the topic, what you need to do is to adjust your bike into any position where the two DOTs on the IXOW Nut is on the TOP. <S> If you are not sure if you are doing it right, refer to the DOTs position of the back wheel when you turn your bike up-side-down. <S> Canyon offers absolute great bikes. <S> But i have seen much better assembling guidebooks, e.g. IKEA. <S> Maybe they could spend some more effort on that.
|
I solved this by (gently) inserting a screwdriver between tab and dropout to fix the tab.
|
Does this rim tape need to be replaced? I replaced my very first tube ever after my tire went flat yesterday. I successfully installing a new tube, inflated it, and left it overnight. This evening the tire was still fully inflated, but after a little riding the tire rapidly deflated again. The new tube has a large tear right at the valve (and after inspecting the old tube, that is also where the tear is. Inspecting the wheel shows this is what the valve hole looks like: Was this the cause of the puncture, and would replacing the rim tape resolve this issue? Or is that normally how it looks? The issue is I don't have a reference of what this part of the rim tape should look like. <Q> Notice the way the person's left hand is holding the pump and the rim. <S> The idea is to stabilize the head of the pump so that no stress is placed on the valve stem. <A> Be careful when removing the pump hose from the stem. <S> I've had the hose pull too hard on the stem and it caused a leak- <S> the stem partially ripped out of the tube. <S> Be sure to hold onto the stem, anchor it, when pulling the pump hose off. <A> Rim strips are not expensive, so if you have doubts, get a fresh rim strip. <S> What they call "rim tape" in this "how to install a rim strip" video is actually what most refer to as a rim strip; rim tape is different. <S> In any case, since you've had two tubes fail in the same location, I'd suggest that you not see if a third one will do the same. <S> Regarding a pump for use out on the road, I'd recommend something with a hose, like a Lezyne or a Topeak Road Morph .
|
One way to get tears around the valve stem is by not supporting the pump head and stem while you're pumping up the tire with a frame pump (the kind where you are pushing on the stem as you pump up the tire, like in the photo below).
|
What wheelset comes on this Trek? Apologies if this is the wrong type of question to ask here, but I was just wondering if anyone knows what particular wheel set comes with this Trek 1.5 2013 bike . I'm pretty sure this is the one I currently own, but other than the fact they are Bontrager I can't figure out what specific ones they are. I recently was hit by a car on my bike and (thankfully) the only damage is to the front wheelset, so I was looking to find out the weight so that I can replace them appropriately. <Q> According to Trek's website : <S> Wheels: <S> And according to Bikeradar's website : <S> Front Wheel Weight: 1370g <S> Rear Wheel Weight: 1970g <S> I fear that you won't be able to replace the wheel with exactly the same thing since they seem to be generic wheels built for this bike. <S> In that price category you might have to buy a set (front+rear wheel) thought, but at least that means they will match. <A> According to my kitchen scales a Bontrager TREK 1.5c wheel (2015) <S> weighs: <S> Rear 1275g with skewer, <S> no cassette,no tyre or tube Front <S> 925g with skewer, no tyre or tube BOTH are 2200g. <A> It's a fairly generic, machine built wheelset with Bontrager branding. <S> They're almost certainly OEM which means you won't be able to by a replacement set. <S> Most likely Alex or similar rims. <S> As you noticed, they're not the lightest wheels out there. <S> A set such as this would typically retail for well under $300. <S> The Shimano R501 or Mavic Aksium One are both good replacement wheels to look at in this price range. <S> Either would be a nice upgrade without breaking the bank. <S> There are some fantastic deals to be had on wheels these days.
|
Alloy hubs w/Bontrager Approved alloy rims You can try the dealer you bought them from, they might have a replacement available or you can look for a different set elsewhere.
|
Chain skip happening seemingly at random with a new chain My bike's a 24-gear trail/road hybrid, and I've had it for about three years (although I've been riding it much more lately than in previous years). For a long while, I've had an issue with chain skip happening seemingly at random, even on level, paved paths, however this issue was always more serious going uphill. I decided to replace my chain yesterday (it's appropriately sized, was pre-lubed, and none of the links locked upon inspection), however on this morning's commute I still got the same amount of skip, likewise more serious going uphill. I've tried using best practices to avoid this issue, as well: I avoid pedalling while changing gears I've checked my front and rear derailleur alignment (and adjusted it as best I could, there's still a very, very slight amount of scraping on the front derailleur if the chain has to travel too far laterally e.g. between my largest front sprocket and the smallest sprocket on the cassette on the rear wheel) I've double-checked that the links don't block, multiple times The teeth on the front sprockets as well as on the cassette don't seem to be overly worn down Two more factors could be relevant to this; this new chain has those "tool-free" break links (you bend the chain to attach or detach one side of the link and break the chain), and I'm a more heavyset guy, so I pedal hard - I think this could be putting more stress on the chain. I'm not sure what else I can do to reduce chain skip. Update: I've gone by my LBS and apparently one of the chain gears is in fact worn down (I just didn't know how to tell, apparently). <Q> Pedaling while changing gears in important to avoid damage to derailleur and chain. <S> Gear shifting proper technique by Sheldon Brown . <S> Shift the gears so that chain is on the middle chain <S> ring(at the pedals) and approximately on the middle gear on the cassette. <S> Verify that the derailer with the chain is vertical, if not adjust accordingly. <S> Also, it is possible that chain may be skipping if the derailleur is slightly bent - in this case bring your bike in to a reputed local bike shop(LBS) and have it checked out. <S> It may save your derailleur from further damage and possible need to replace it. <S> Changing to an easier gear just before you climb and spinning pedals (lower effort but slightly higher pedal cadence), instead of mashing on a tougher gear (applying greater force and lower pedal cadence) helps avoid chain skipping. <A> When a chain wears, the cogs wear down together with it and will not mesh correctly with a new chain. <S> Worn cogs do not look like the teeth would be actually wearing down. <S> Instead, the teeth get narrower and eventually develop an asymmetric "shark fin" shape. <S> If you do not know exactly what to look for, a worn out cassette looks like new. <A> It turns out that the issue was caused by a worn shifter cable casing -- the plastic tubing. <S> LBS replaced it at around a fifth of the price of replacing the cassette and/or chain gears, and everything works like a charm now.
|
Your cassette and possibly chainwheels are worn out.
|
Is the durability of more expensive chains better than cheaper ones? Do expensive chains last longer? I get 300-400 miles using Wally World's $10 8 speed chains while riding off road or dirt. I monitor and replace the chain at close to 1 percent stretch. Would a 'better' (i.e. more expensive) chain last longer? Has anyone done a comparison of chain life and longevity vs price? <Q> No. <S> The ones with extra plating do look nicer and provide some corrosion resistance, but it takes almost no effort to keep your chain rust free. <S> There are differences between various manufacturers, but in general those relate to shifting and how the quicklinks work, not the chain life. <S> (i.e. if you like how SRAM chains work on your bike, buy the cheapest SRAM chain. ) <S> 300/400 miles is a very short life span for a chain. <S> Two things might help you extend the life of your chain. <S> If your rear cluster is worn, that will quickly wear out a chain. <S> If you have lot's of miles on the rear cluster consider a replacement. <S> Any time you replace the rear cluster you should replace the chain. <S> Front chainrings can also cause wear, but they take a lot longer to wear out. <S> Excess lube on the chain. <S> In a dusty dirt environment any lube on the outside of the chain creates a grinding paste that will wear a chain quickly. <S> Chains actually move very little. <S> All they really need is enoughlubrication to prevent corrosion inside the rollers. <S> If you're riding indirt and dust wipe the outside of the chain as clean as possible before installing it. <S> Point 2 is controversial, all I can say is I ride on fine clay soils that destroy chains and it has worked for me to greatly extend the life of both chains and expensive gear clusters. <A> I get 5000 to 10000 kilometers from mid-priced 20€ Campagnolo C9 chains. <S> I would say this is money well spent. <S> Of course, as other answers state, riding conditions and maintenance do effect the chain life. <S> In my experience SRAM and KMC chains are nowhere near as durable with similar maintenance. <A> Unfortunately it depends a lot on the specific manufacturer. <S> I usually get around 1500 km (or more) out of SRAM and Shimano chains. <S> I always buy the least expensive option and usually 9 speeds. <S> (All of my bikes are 3x9 speed mountain bikes) <S> And I ride mountain trails in muddy or otherwise very humid conditions. <S> I clean after each ride if needed, but when the weather permits I skip cleaning up to 3 or 4 rides. <S> I use Finish Line Wet lube, or 3 in 1 and even cheap 3 in 1 knockoffs usually sold in my country. <S> Except that I'm currently in another country, And used up an 8 speed Taya chain in just 500 km of city/road-ish riding and using Finish Line wax lube (A lube for dry conditions). <S> I'm in a city that is almost flat, but it is very dusty. <S> Due to the short duration of this Taya Chain I switched to 8 speed Shimano Chain on Finish Line's dry lube. <S> The change is at this point to soon to review, but as short as the first ride I noticed much better shifting performance and quieter operation under heavy load.
|
On the other hand if you replace your chains regularly a rear cluster can last a very long time. The only advantage of expensive chains within a specific brand is the minor reduction in weight.
|
Bike suggestions for a heavy rider I'm a 5'10, 300lbs rider looking to get back on a bike after many years and many pounds. I owned a 1999 Trek 7700 Multitrack and road about 20 miles a day for many years before injuries, age and time took their toll. I want to get back on a bike - new or used - in the $400 range. Any suggestions? I loved the hybrid, but I'm not sure the rims/tires can handle my current weight. My target weight is 220, which was my weight when I used to ride daily. Initially, I'll be riding about 10 miles per day on level pavement. I was looking at some Trek 7.x fx bikes, but am open to any make/model/year. <Q> Your current weight is at the high end of the limits <S> Trek puts on their bikes . <S> Here's the relevant section from the Trek FAQ: Rider weight limit of 300lbs: <S> Hybrid bicycles with 700c wheels, tires larger than 28c, and flathandlebars City bicycles: hybrids with special equipment, cyclocross bicycles:with drop type handlebars, knobby 700c tires, and cantilever or discbrakes Mountain bikes of all types including: standard, race, cross-country,heavy-duty, trail, all-mountain, freeride, and jumping bikes of boththe hardtail and full suspension variety. <S> I suspect that other makers have similar limits. <S> You don't say much about your riding style, so it is hard to be very specific, but there are some things to keep in mind: <S> Make sure <S> your wheels are well trued and tensioned, the biggest cause of wheel failure is probably spoke breakage caused by spokes that are too loose. <S> Find a frame that will take wide tires and use them – wider tires will be able to support your weight with lower pressures which reduce the chance of pinch flats and rim damage. <S> Wider tires will also make the bike more comfortable and by running at lower pressure will reduce the stress on your rims. <S> Good luck! <S> If you're starting with a bike in decent condition and aren't riding it too hard, I'd guess that if you take care of the items I mentioned above the bike will do just fine. <S> Your weight is going down after all. <S> I wasn't as heavy as you when I started riding again – but I was up there (on the far side of 260). <S> I started on the bike I had – an old steel Trek 530 frame with 32 mm tires (the biggest I could fit into the frame). <S> I'm starting to think I'll be able to break 200 this year. <S> If you're looking for ideas about getting started on riding again, I'd highly recommend Grant Peterson's book Just Ride . <S> There is good thinking about riding for the joy of it and also some ideas to get you thinking about how to exercise effectively. <A> I have the same problem. <S> My weight range from the time I started using this bike was from 425 to 325 pounds. <S> I weight 375 pounds right now. <S> I use a specialized hardrock mountain bike with a sun rhino double wall rim, 4130 steel frame. <S> I got the bike in 1998,99 some time ago. <S> The only thing I have changed is tires, chain and crank bearings. <S> I use to be easy on the bike but got to trust it more and more. <S> I live in new Orleans area and use it to ride on levee. <S> I use to walk the bike up the levee <S> so I would not break spokes <S> but now I just ride it up. <S> The bike has been good and I am not really easy on it. <S> I put street tires on it and air them up to be real hard. <S> I have blown the tubes because I like them to be hard. <S> I am looking to get a new bike and am going to try a hybrid with stock tires and ri until they fail. <S> I am going to be easy on them. <S> I will see how strong these new bikes are. <S> I don't trust the forks and axles and will keep an eye on them. <S> On another note <S> I also have a (world sport schwinn) old steel frame <S> and I ride it a few miles a month. <S> It has been a strong bike. <S> The rims are steel and not aluminum. <S> They have worked good and I had no problems with them. <S> I tend to be easy on that bike and check the forks regularly before I ride. <S> O by the way I been riding as much as 50 miles a week on the mountain bike. <S> Just like anything the chain and bearing will need to be checked as you put miles on it. <A> I'm 300 lbs, and I ride a stock <S> Trek 7700 Multitrack <S> 20 miles a day with no bike problems on hilly tar roads. <S> This bike is also very comfortable for a larger rider
|
Take time to find a bike that fits you well, it will be much easier to keep riding if you are comfortable.
|
Which road shifters will work with Shimano Deore (M)610 Groupset? I'd like to get the Shimano Deore 610 Groupset 3x10 but want to run drop handlebars with brifters (brakes & shifters combined) but it seems like this is almost impossible... I've been told by one support person from the online site I'm buying from that I can use 105 brifters and front deraileur and this might be compatible. I've been told by another support person to just go Tiagra 4703 but I really would prefer V-Brakes (descending the Alps), the lower gear ratios (climbing the Alps) and the €100 saving of the Deore. I know I've got two issues, gear indexing and brake cable pull ratio but is there any brifters that will allow me to use Deore successfully without huge amounts of faff? Thanks... <Q> Unfortunately, you can't use 10-speed Shimano road brifters with 10-speed Dyna-Sys mountain bike drivetrains. <S> They just have different cable pull ratios. <S> You're limited to a few options if you want to run drop bars with 10-speed Shimano: <S> Mount your existing MTB trigger shift on your drop bars. <S> This means you have to take your hands off the hoods and drops to shift. <S> Get 10-speed <S> Dyna-Sys compatible thumb shifters from Microshift. <S> You must take your hands off the hoods and drops to shift. <S> Get 10-speed <S> Get Gevanalle GX brake/shifter kit, you must shift from the hoods using <S> indexed bar end shifters mounted on front of brake levers. <S> Definitely unsupported by Shimano. <S> May be limited to 11–32 cassette instead of 11–34 or 11–36. <S> YMMV. <S> However, you can mix and match road and mountain components with most SRAM 10-speed drivetrains. <A> No -- You've got several problems here. <S> 10 speed mountain Shimano has different cable <S> pull than 10 speed road Shimano (which is the same cable pull as <S> 9 speed mountain Shimano, I believe, <S> so if you double check this, you can drop a 9 speed Deore in). <S> Then, you have the mountain vs road FD, which if you're using brifters, you need to use a road FD. <S> Front derailleurs are cheap anyway, so I don't see why you'd want to save money here. <S> The V-brakes are pretty easy to deal with with a travel agent (a pulley to let you use short pull levers with V-brakes) or you can use mini-V brakes and not use a travel agent. <A> The newer brifters (such as the Tiagra 4703) are "Super SLR" on the brake pull amounts. <S> This means they work even better with Mini-V brakes than older brifters that had the gear cable coming out the side. <S> You can get Tektro and TRP's in several arm lenghts -- depending on what you are looking for in your setup. <S> 80mm (926AL), 84mm (TRP8.4), 85mm (BX3V,BX1V,RX1,RX3,RX5), 90mm (TRP9.0,RX6). <S> Typical Shimano MTB V-brakes are 107mm. <S> The longer the brake arms <S> the less force you have to apply to the levers, but <S> they also require you to put the pads closer to the rim <S> so you don't run out of brake lever travel. <S> Shorter arms give you more rim clearance, at the expense of mechanical advantage. <S> I highly suggest using V-brake noodles with an adjusting barrel to make releasing the straddle cable much easier for wheel changes.
|
You could try road brifters and a long cage road derailleur with a 10-speed mountain cassette. Dyna-Sys compatible bar end shifters from Microshift. So you could use something like force shifters with X9 derailleurs with less trouble. You must shift from the drops.
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.