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Questions about tubeless tires I keep getting a lot of pinch flats even though I've pumped my 26x2.00 wheels to 280Kpi (65psi) and I've been thinking about converting to tubeless. But I don't have both tubeless ready tires and rims. What if I buy just the tires but use my current rims, will it work? <Q> Without tubeless ready rims it will be hard to get a traditional tubeless setup to work. <S> What could possibly work might be a ghetto tubeless setup as described here: <S> http://www.mtbtechniques.co.uk/MaintananceGhetto.html <S> Altough this is specific for mountainbikes. <S> On a road bike I would suggest getting proper rims for a tubeless setup. <A> In the earlier days of tubeless it was very common to do this on mountain bikes. <S> (It doesn't work on road bikes and was often regarded as unreliable for cross). <S> Instead of just modern tubeless tape, a thick rubber rim strip sized to the rim width was also used to "build up" the rim well height to create the seal with the tire. <S> The most common product for this was (and still is) <S> the Stan's Notubes Tubeless Conversion Kit. <S> These came for rims of different diameters and width and were labeled with a few named rims they were known to be compatible with and then said something like "and other __mm rims." <S> Tubeless conversion kits for non-tubeless rims and tires were popular in their time and can work fine but can be frustrating to deal with and often require trial and error, especially for a tire that's not tubeless ready. <S> Setting them up has an air of experimentation, again especially with a conventional tire. <A> Like nollak said , trying to convert non-tubeless rims to run a tubeless setup can be made to work but isn't ideal and comes with risks. <S> A couple of things could help avoid pinch flats: Ensure your rim tape is in good condition. <S> Ensure your tubes are not twisted when you replace them <S> Ensure your tubes are correctly seated when you replace them <S> Run your pressure higher if your tire indicates it can be <S> Use a different tire as the shape or performance of the tire might provide more cushioning with less risk of pinches
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Rim tape helps keep the tube in position and if it is ripped, dirty, etc it might be causing the punctures.
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What road bike size to get? I am very new to road bikes and have decided to buy one. The problem is both shops I have gone to said I should get a 54cm frame, even though I'm only 5'5. This seems to go against a lot of online information and my friends advice. What should I do? <Q> 54cm does seem large for you. <S> I'm between 5'8" and 9" and ride a 54 or 55cm ( <S> and I have relatively long arms). <S> Some thoughts: <S> Some models are effectively larger or smaller than their seat tube measurement. <S> Bicycle shop staff may have been taking that into account for a specific bike you were interested in. <S> Look at the sizing charts that some manufacturers publish e.g., this from Trek . <S> Print it out and take it with you when looking at bikes. <S> Sit on or ride a 54cm, then say 'that feels too big'. <A> Basically the size of the roadbike depends on the length of your legs. <S> First you need to measure that <S> and then you can decide which size you need. <S> Furthermore the geometies of the frames also vary, so you can't compare a 54cm frame of company X fo 54cm of company Y. <S> Always check the frame geometry. <S> Usually, if you are more a racer type, you would choose a smaller frame and larger stem, due to better steering and handling properties of the bike. <S> Have a look at Canyon size and positioning tool/calculator to find out which body measurements are important and should be consideren (torso length, shoulder width, ...) <A> If this is your first road bike then perhaps you should do one of two things: buy from a store that has a good exchange policy. <S> Many stores will let you return a bike in 30 days in exchange for another bike they have. <S> This way, if you really feel it’s too large, you can downsize. <S> Road bikes feel very different from mountain bikes which feel different from recumbents. <S> By buying used, you can sell it once you know what you like or dislike and <S> what size or posture feels right. <S> Features such as disc brakes might not be for everyone, etc.
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often it’s good to buy a used bike when you shift to a new style of biking. Take a knowledgeable cycling friend with you when looking at bikes.
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OK to ride with a slightly bent mech hanger? My rear derailleur took a knock from a fall, and the entire shifting range moved inwards by about one sprocket width. I suspect, but am not sure, that the mech hanger got slightly bent (could be completely wrong, not really sure how to tell). I was able to counteract this by adjusting the limit screws, and the derailleur seems to be shifting well over the entire range. The way it's set up currently I can no longer push it into the spokes by hand (i.e. it's the limit screw and not cable tension that stops it). I am tempted to just leave things are they are. Is it OK to ride like this, or are there compelling reasons (safety, long-term reliability, etc) to figure out what got damaged and repair/replace it? Here are some pics: <Q> Derailleur hangers are supposed to be, to some degree, a component that bends to save the derailleur. <S> The hanger on one of my bikes seems to get bent at the slightest impact. <S> I'm considering ordering a spare and carrying it around in my tool kit. <S> If the indexing was severely affected by the fall (moving inboard <S> a whole sprocket definitely counts as 'severe'), you need to address the problem properly. <S> A bent hanger is going to affect shifting and put extra strain on the chain, and you risk the cage hitting the spokes when changing to the largest sprocket. <S> You can eyeball the derailleur cage alignment by looking down the chain-line from the back of the bike - see image below from this question . <S> The derailleur cage should appear to be parallel to the chainrings. <S> My LBS only charges $20 for hanger alignment and indexing adjustment (I'm in the USA). <S> Worth it to get the hanger straight and avoid associated problems. <A> Derailleur hangers are usually aluminum, but they're pretty substantial and anything that could put significant stress on them while riding is likely to come from something that would be catastrophic even should the hanger survive the event totally unscathed. <S> I'd just remove the rear wheel, maybe unscrew the hanger itself from the frame (might not even need to remove the rear derailleur itself or even the chain), and inspect the hanger, looking for cracks or deformation beyond a simple bending of the main part of the hanger. <S> For example, is the screw hole ovalized or otherwise distorted? <S> If there aren't any cracks nor any distortion, I'd ride on it. <A> There's some theoretical safety risk in that if your gears are skipping around or not engaging totally reliably, the bike could not do what you want it to at just the wrong time. <S> If having a shop fix it with a hanger alignment tool isn't in the cards for whatever reason, then you can probably make it better than it is now by poking a wrench into the derailer pivot bolt to use as a lever arm and aligning the hanger by eye that way, eyeballing the parallelism between the pulleys and the cogs in both axes. <S> The derailer won't be affected. <S> This is a lot better than leaving it as-is. <S> Whenever one aligns a replaceable hanger, there's some distant risk of it breaking, but it's rare and usually more goes along with a more severely bent or visibly cracked one.
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Things like a chain side plate coming loose and catching on the rear derailleur cage or the rear derailleur cage itself getting caught by a rear wheel spoke aren't going to end well even if nothing happens to the hanger at all.
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Pedal foot position - balls or arches I notice that when I pedal that I mostly seat the pedal in the arches of my foot naturally. I also notice that the cycling shoes tend to seat the cleats in the balls of the foot area, as do other cyclists. I was curious about the justification or pro/cons of either. When I try to pedal in the balls of the foot location I find it a bit better to be aggressively pedaling, but my foot slowly drifts back to the arches position. I ride flat pedals only. <Q> The ball of the foot gives a large, strong, stable area to use on the pedal, and gives you a nice lever to use your muscles effectively. <S> Conversely, the arch of your foot is soft, elastic and not stable. <S> Picture your foot <S> as you walk slowly barefoot, you push down hard on the ground with the ball of your foot, and the arch acts as a big rubber band to help spring the heel up and launch you forwards. <S> You can walk or run solely (ahem) on the balls of your feet, without using your heel, thanks to this elasticity. <S> So what... <S> Well, the ball of the foot is a strong, stable fulcrum for your foot while the arch is not, which is why you've noticed the ball is a better location for "aggressively pedalling" i.e. better power transfer. <S> You probably also recruit lower leg muscles more naturally and powerfully using the ball. <S> I don't know if there is risk to you using the arches on the pedals (maybe someone else does) <S> but there are definitely benefits in learning to use the balls of the feet. <S> You'll use your joints and muscles more naturally, be more powerful for the effort you put in and look super cool too. <A> When you push the pedal down your calf muscles have to work to keep your foot roughly parallel to the ground. <S> Placing the foot forward on the pedal, near the ball, increases the lever your calves have to work against. <S> Placing the pedal further aft on you foot, towards the arches reduces the lever, and in turn the strain on your calves. <S> There are a couple of consequences that make both positions useful for different riders. <S> For high power output over a short time it might be better to place the forefoot over the pedal axle (keep it still behind the first two metatarsal heads). <S> As this allows another muscle group, calves to push through the stroke. <S> For endurance placing the foot further aft, towards the arches, has several advantages. <S> One may expect the calves to tire more quickly than thigh muscles (less muscle volume). <S> There is also an argument that calf muscles are not as well provided with oxygen and nutrients since they are further 'downstream' in the cardiovascular system. <S> (I did not find reliable sources, and am sceptical about that.) <S> Foot placement further aft also allows a more powerful downstroke. <S> Most cyclists with clipless pedals tend to mount their cleats too far forward on the foot. <S> One may observe that when watching cyclists form on popular climbs: Fatigue of calf muscles leads to heel drop. <S> During the downstroke the heel drops below level. <S> Taking away force from the downstroke. <S> Riders sometimes compensate this by pointing the forefoot downward all the time. <S> Both are very visible from the side. <S> What may be a consequence for you? <S> Your foot hurts because of pushing near the arches, where the foot is not as strong, as Swifty pointed out in their answer. <S> If that happens, move your foot further forward. <S> (For example, I have to place my cleats too far forward, otherwise I get unbearable pain in my right foot.) <S> Since you are riding flats you don't even need to think about foot position. <S> You will simply get to the optimum position by feel. <A> It's up to each rider to determine which is best according to their cycling discipline. <S> For a track racer, forwards is probably better. <S> For MTB though, you pretty much want to go as far back as your shoes will let you. <S> Your calves will thank you! <S> Some pro MTB riders even go so far as to extend the slots in their shoes with a dremel so they can mount their cleats farther back. <A> Well, how about instead of opinion, we use some real science? <S> "The practical implication of these findings is that adjusting the anterior-posterior foot position on the pedal does not affect cycling economy in competitive cyclists pedaling at a steady-state power output eliciting approximately 90% of VT." <S> Both positions are equally efficient. <S> Ball of foot is used because... <S> it's just the way things were always done. https://www.researchgate.net/publication/6886747_Is_economy_of_competitive_cyclists_affected_by_the_anterior-posterior_foot_position_on_the_pedal
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The lever effect of the foot means that: placing the pedal spindle closer to the toes results in high sprint power but lowered endurance placing the pedal spindle closer to the heel results in lower peak power but better endurance Please consider to ride as you like, without any attempts to train yourself to use a different foot position. Contrary to cyclings old traditions, where a 'round' stroke is considered an ideal, it is much more efficient to apply force to the cranks at angles where the mechanical advantage is best, ie at the downstroke. For a crit racer, forwards-ish is good.
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Why do I lose so much power/speed in an aggressive position? I've heard many cyclist say they can go faster (and are more comfortable) with a large bar drop. If my bar is more than 5cm below the saddle (even by 5mm) -- or if I increase the reach -- my power drops at least 20% (3-4 MPH slower up a 10% grade). Is this because my torso is 10cm+ shorter-than-normal compared to my legs? Or, can it be because my hips are large for a guy? (Isn't a large pelvis/hips one of the reasons that woman tend to need a more upright position?) Could it be that the saddle position isn't ideal? (If I lower or move the saddle rearward from my current position -- about KOPS & HOP -- the opposite occurs: I'm slower when upright, then gain power as I force myself into a long, low position. But, comparing the 2, the more upright, higher/forward saddle is noticeably faster then the aggressive, lower/rearward saddle.) Is it simply a matter of "getting used to" a lower position? (If I lower the bar 5cm, and just continue riding that way, will I eventually be able to put out the same power I did while more upright?) I've had SIX bike fittings done over the years, every one making me LESS comfortable and SLOWER, so there's no way I'm spending more money on that. (Every fit was completely different. One had the bar 52cm from the saddle, another set it at 59cm! One had the saddle 6cm behind BB, another had it 12cm back!) Since I live and ride in the mountains -- I live 600 ft up the side of one! I'm MUCH more interested in power/efficiency than I am in getting aero (if I need to be more upright to climb as fast as possible, so be it -- but it would be nice to be reasonable aero -- lots of descents, too! -- if I could do so without the power loss. <Q> I've heard many cyclist say they can go faster (and are more comfortable) with a large bar drop. <S> I think this initial assumption is somewhat faulty. <S> Most riders will find they are less comfortable and can make less power in a forward, aggressive position. <S> I certainly find that to be the case myself. <S> (I'm a reasonably fit rider who can hang with the A group on local rides.) <S> You may just need to accept that your anatomy and strength just don't allow for a aggressive riding position. <S> You can get in the drops on descents where max power output is less important compared to getting more aero. <A> So there's two options with stock bikes: A) <S> You chose, based on reach, a smaller frame and high seatpost. <S> This will probably mean that you need to also keep the handlebar high with several spacers. <S> And probably you have a more upright stance. <S> But you can produce power. <S> B) <S> You chose, based on standover or seat tube length, a bigger frame that makes you less upright and more aero, no need for such a high seatpost or taht many handlebar spacers, but you feel like you can input less power. <S> I think A is the best choice for long legged people. <S> But if the ratio leg / torso goes very off the norm, it's possible that a frame with the appropiate reach is then really small in term of seattube length. <S> So if you had to get a bigger frame, the solution is probably to push the saddle to the maximum forward. <S> I've seen people that go as far as to turn the seatpost, so that the setback becomes "setforward" allowing to place the saddle quite forward and reducing effective <S> reach length while the legs remain in that sweet spot over the cranks. <S> And then probably drop the handlebar height a bit. <S> The thing with saddle forward is that you may also need to move cleats a bit back into the arch of the feet. <S> My suggestion, only based in my experience as someone with long legs compared to torse, is then, push saddle a lot forward, keep it parallel with ground, drop a spacer or two, and put cleats on shoes a little bit closer to arch. <S> It's working for me. <S> Also, if your seatpost has setback, change it for a straight seatpost, or turn it so that it looks to the front.t <A> Well, after some more fooling around with my fit, I think I may have figured it out. <S> Apparently, when trying to get lower and/or longer, I was bending my back more than "rotating the hips. <S> " <S> Tried numerous saddle positions, and in every one -- even those that were obviously wrong -- I managed to go noticeably faster if I made sure to rotate my hips. <S> (Funny how after doing that, the bar felt like it was too CLOSE and HIGH!) <S> I'm now able to get the bar 8cm below the saddle, and 3-5 cm further away before my speed/power drops. <S> (In fact, with the rotated hips, I also lose power if the bar is too CLOSE! <S> There's now about a 2 cm "sweet spot" where I can maintain max power) <S> My back is flatter now, and my torso/arm angle is now about the recommended 90-degrees.
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Long legs relative to torso create this problem, where a frame that has an appropriate top tube length has usually a seat tube that is short for you, so you need to have a higher than usual seatpost. If you are riding in hilly terrain and are concerned with making your max power, set up your bars in a less aggressive position that is comfortable for you and just ride on the hoods.
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Lever pulsates while braking I installed a new front float rotor, the ones that you can get from AliExpress. I have Deore XT brakes. While using the front brake the lever moves back and forth while pulling it. I inspected whether the rotor was bent or the caliper was not properly aligned but everything is okay. I can't figure out what the problem is or is it expected to work like that for float rotors. Need help. Please <Q> Assuming that you've already checked that the rotor is true (and out-of-true rotors are more responsible for rub than pulsation), I would take a micrometer and measure the thickness of the rotor in multiple places. <S> You are likely to find that it was not machined correctly. <S> Also, check the surface finish of the rotor on both sides. <S> It doesn't matter what it is so much as that it is uniform, all the way around. <A> This causes the calipers to go in and out as the wheel rotates. <S> There's nothing you can do to fix that, except get better rotors. <S> (There's no such thing as a floating rotor. <S> The calipers may be floating, but not the rotors. <S> See here, under "two types of disk brakes". <S> The article is about automotive brakes, but a bicycle hydraulic disk brake is basically the same mechanism.) <A> Place a steel ruler along the brake disc and check for gaps. <S> There is not much brake disc with lots of slots. <S> Push the bike slowly whilst applying some pressure to identify the area this happens. <A> The rotor and the brake pads were probably not bedded in properly. <S> Happened to me too. <S> Clean the rotor surface with isopropyl alcohol and change the pads. <S> If this does not work than check the caliper alignment and if the rotor is in someway bent.
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Most likely explanation is that the rotors were machined improperly, so they're not the same thickness all the way around.
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Cycle touring. First chain failure. Thoughts on cause? Was pedalling up steep hill on gravel road. No gear change. Just seemed to go mid push. Was very steep and out of saddle....had to push the remainder of way! <Q> Well, only really one proximate cause for this: chain was weakened through wear and fatigue (it looks a bit old) <S> , you applied enough force to break it. <S> Likely that there is no single event that broke or weakened the chain. <S> Chain failure happens. <S> Think of it a a rite of passage. <A> The chain could have been damaged earlier, during a poorly-executed shift. <A> Possible causes: <S> Worn chain: <S> Check your chain wear regularly using a chain wear gauge. <S> If the 1.0 side falls through it’s high time for a new chain. <S> For me with 10-speed chains the 0.75 side usually falls through after about 2000km. <S> Bad installation. <S> You should never re-use a normal chain pin. <S> Only use a “master link”/“missing link” or a special closing pin. <S> Previous damage. <S> Maybe you previously had a bad shift or bent the chain when uninstalling the back wheel etc. <S> Try to be careful, chains are strong in the direction of their links but weak when twisted or loaded sideways. <S> I’ve never had a broken chain despite bicycling tens of thousands of kilometers, often through mud and with luggage under high power. <S> Therefore I wouldn’t carry around a chain tool despite what others have suggested. <A> I personally haven't seen a metal failure in a chain plate. <S> Clean it up and have a look under a microscope at the plate to see what the fail edge looks like. <S> (Your cellphone will take a photo through the microscope nicely) <S> The failure modes I am familiar with result in popping the plate off the pin. <S> (e.g piece of gravel between chain and sprocket)
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Or the chain and/or sprocket may have simply been worn out -- a worn chain/sprocket combo causes "chain suck" which can break the chain. It is hard for me to imagine a failure mode other than a manufacturing defect (crack) in the plate.
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Is 25 km/h average speed good? What speed should I aim for? So, I recently got into road cycling and have been riding for a few weeks. My average speed for most of my rides is around 25 km/h for the first 40 km and drops to 15 or 20 km/h for the next 20 or 30 km. I want to know if the speed that I'm riding at is considered as "slow" or "walking pace" or is the speed that I'm going at pretty good. I'm not sure what speed I should be aiming at. Note: I am preparing for long distance rides, mostly flats more than 80 km. So I want to know what speed I should be aiming for, not to win, but the speed that one should ideally be at. <Q> There is no such thing as an ideal speed you should be aiming for. <S> It doesn't matter how fast you ride, there will always be faster riders, and there will also be slower riders. <S> The main thing is that you give it your best and try to enjoy your ride. <S> At events here in the UK it is typical to see riders averaging from 16-35km/h and everything between. <S> Edit: Advice above is for a typical sportive ride - if you have intentions to race things are a bit different and you should expect to need to be able to hold a bunch travelling at 35-40km/h for 2hrs for entry level road racing. <A> Based on comments, your average speed is fine, and is decently fast. <S> More-so when you consider it includes stop time at lights and so on. <S> Your endurance needs training - to do this <S> you need to ride slower, for longer. <S> Another option is to find a destination that is about 2 hours / 40 km away, ride there, lunch and rest, then ride back in the same day. <S> Aim to keep that 20 km <S> /h speed up the whole way. <S> Once you have that comfortable, add some very short "intervals" of max power effort for 10-15 seconds, with 10 minutes of casual riding between them. <S> Get 4-6 of them in on each leg <S> and you're training nicely. <S> Finally work on shortening the midpoint stop. <S> Maybe scarf down a gel or bar but stay over the bike, and ride off pretty quickly. <S> You want your muscles to change their behaviour and be able to keep working at the same lower effort for longer. <A> 25 km/h for 40 km isn’t slow (unless you are comparing yourself to the professional peloton). <S> If you are just getting into road cycling you're are likely not performing at your actual potential. <S> Even if you have good cardiovascular fitness your body will not be adapted for cycling. <S> Instead of thinking in terms of a target average speed, think about what training you can do (even if that is just general riding a couple of times a week) and what improvements you can make with that training. <S> You'll also pick up knowledge about things like nutrition and fueling a long ride. <A> As others have pointed out, average speed isn't a good measure of fitness or competitiveness on its own. <S> I would recommend you look into an app like Strava. <S> If you ride the same course regularly, you will be able to see how your times/speeds vary over time. <S> You can also look at how others are performing on the exact same parts of a ride. <S> If you want to take it to the next level, you could add a power meter so you can track your FTP, max watts, and watts/kg. <S> This is a much better gauge of effort than speed alone because it accounts for varying terrain. <S> It is easy to go overboard when it comes to integrating data into your riding, but there are definitely some great tools out there help focus your training and understand your progression.
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One of the best ways to improve is to ride with other people who are just a bit faster or who have more endurance than you. However, you may benefit from being able to compare your efforts to others and also track changes in your own results. If you have a speedo, aim to ride at 20 km/h for more than the 2 hours.
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Skipping on new chain, new cassette, new derailleur For a long time I have been having issues with chain skipping on my 1999 Trek 6500. I took a video to illustrate exactly what I mean by "skipping": Over the last few months, in the course of trying to fix it, LBS has persuaded me to replace the chain, rear wheel & cassette, rear derailleur, shifters, and cables. Derailleur hanger angle has been checked, limit screws and cable position adjusted. None of these have completely fixed the issue. As it is now, I can reliably reproduce the issue by riding over a large bump, or doing a bunnyhop to cause a physical shock to the bike, then riding for several seconds while standing up and accelerating hard. If I remove the bump from the equation and just accelerate over smooth pavement, the issue does not occur. There is generally one skip per bump - i.e. After a skip occurs, I usually must induce another bump before it will skip again. What other candidates are there to investigate as the cause of this issue, and how would one test them? <Q> You could try removing a link or two from your chain to reduce the amount of slack in it. <S> (Ensure you can still reach your entire gear range with the shortened chain length) <A> If this is happening on a new chain and cassette, suspicion would turn to insufficient chain tension, specifically caused by weak or broken tension springs in the derailleur - but the derailleur has been replaced as well. <S> Does this problem occur more in the small or middle front ring? <S> I would check the chain length, just to rule that out. <A> I see that 2 chain rollers come from beneath improperly engaged, and those are the ones that cause the skipping. <S> Maybe the upper jockey wheel rests too close to the cogs, or moves up and down too much (possibly hitting the cogs), and somehow is causing a few rollers to engage earlier than they should, before the ones in front of them had time to engage properly. <S> But before tinkering with that, I would clean and lubricate the chain really well and see if it stops the skipping. <S> The chain might be too rigid and not wrap back properly around cogs or jockey wheels after it has been airborne because of the bump. <S> A video from the side would also be helpful, to see what happens with the chain around the jockey wheels.
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A chain that is too long may cause skipping.
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How to prevent brake quick release from opening on rough roads? On rough roads or when there is a lot of vibration, the quick release on my front brake will sometimes pop open. Is there a way to prevent this from happening? If it helps, the bike is a 1995 Trek 370, which has Shimano 250EX brakes and Shimano Exage 300EX levers (according to BikePedia ). <Q> Presumably the QR lever originally had enough friction to stay closed but has worked loose or a plastic washer or bushing that provided the friction has degraded. <S> Obviously keeping a brake functioning is a high priority <S> Maybe you could use a small zip tie or the type of wire used to stop bolts coming loose. <A> Criggie is right of course, so I’m going to amend this a bit. <S> The.QR isn’t really serviceable so if it’s not functioning the unit should be replaced. <S> If you must ride to the bike shop to have this done, you could choose to bypass the QR by opening it fully and re-fixing (tighten) <S> the cable to take up the slack. <S> Might be a bit hacky, so proceed at your own risk etc. <S> But I’ve seen people set their bike up like this on accident even, not realising how QR works. <S> Sometimes bike maintenance just means replacing worn out parts. <A> That photo shows a pretty filthy bike. <S> I'd start with a full disassemble of the rear brake caliper, and clean all the metal parts, and especially on the friction areas. <S> Then I'd buff the whole thing with brasso or JIF cleaner. <S> Then reassemble and see if it improves. <S> If not, you could rough up the friction surface under the quick release using some sand paper. <S> If the main spring in the brake caliper is weak then this may be a losing battle, because sourcing replacement parts is hard. <S> In this case, just explore for some more modern double pivot calipers, and fit them up with new brake cables. <S> The temp fixes suggested by others are exactly that - temp fixes. <S> I wouldn't even ride this bike if your braking ability is compromised. <A> One other idea: I guess for the quick release to come loose the cable temporarily has to be unloaded by vibrations (try releasing the QR while pulling the brake, it shouldn’t be possible). <S> Maybe the springs are too weak or the cable is too dirty? <S> Is brake action smooth and easy? <S> If not, you might want to replace your cables and housing first.
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Probably the simplest solution is to use a bit of tape to hold the lever closed, but tape may come off. You should stop riding the bike until you replace the brake if your braking is compromised.
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Hire road bike for one day for race (never ridden one before)? So I am thinking of doing a triathlon in a couple of months. I've been training on a hybrid bike and have only ever ridden either hybrid or MTB. Your probably thinking, don't do it you're mad, totally different riding position, much narrower tires etc. So what do you think? I would have an evening with the hired road bike the day before the race, do you think I can literally jump on a road bike for the first time and for a race and pull it off or am I kidding myself? <Q> In your first tri , you’ll have all sorts of new things to concentrate on, I don’t think an unusual bike should be one of them. <S> When I’ve seen people ride road bikes for the first time, <S> it’s the gear shifting that’s often trickier and more distracting than anything else. <S> I’ve seen people take more than one ride to get the muscle memory to change gear in the direction they intended. <S> It becomes intuitive, but through practise. <S> For your first tri you’re also only racing against yourself. <S> So if you know how fast you normally ride in training, you can compare how fast you race, and know if you’ve done a good job on race day. <S> If, afterwards, you want to do a second triathlon, put the rental fee you save towards a road bike to train and race on. <A> Yeah you can do this - if - your only goal is to finish the race and don't care where you place; and you don't mind being very uncomfortable and can accept a bit of danger from trying to ride a totally unfamiliar bike as fast as you can. <S> Actually I'll go back on that. <S> This could be dangerous. <S> If I were another competitor I'd not be happy about someone riding a very unfamiliar bike near me, so please don't do this. <S> Perhaps try renting the bike a few times before trying it a race, so you at least have a chance to get familiar with the handling and braking. <A> Renting a bike to ride in a race is not a good idea. <S> One example, Rapha's bike hire , expressly forbids it. <S> All warranty and damage liability waivers will become null and void. <S> You would be liable for the full price of the bicycle in the case of any damage. <S> As other answers have said, you will need practice to perform adequately on a road bike and risk crashing and serious injury. <A> This isn't a good idea. <S> The different riding position will likely make some combination of your back, arms, legs and neck sore for the first few hours of riding. <S> It will take much longer than that to get comfortable riding on the drops, though probably less so if you're fairly flexible. <S> At least a few hours to get to the stage where you can fairly reliably translate <S> "I want to shift up/down at the front/back" to the right hand movement and longer until you can do it basically every time without thinking about it. <S> Having a new bag of gear ratios means that it takes a while to get back your intuition of "I need a slightly easier gear and I need to change to the small chainring – how many gears should I shift at the back?" <S> Road bike handling is significantly more responsive (complimentary term)/twitchy (pejorative term) than hybrid handling. <S> Most of the time, this doesn't make a big difference to anything much but, for example, it took me a few weeks to be able to look over my shoulder while on the drops without moving significantly to the side; I could ride essentially arbitrary distances with my hands off the bars of my hybrid <S> but it took a while to be confident doing it at all on my road bike. <A> Yes, you are kidding yourself. <S> You know how to ride the hybrid, so you should ride it for the race. <S> You will be faster on it than on the fastest road bike. <S> Somebody as fit as you who is used to a road bike <S> will beat you, but renting a road bike for the day is not the answer to that. <S> None of that happens overnight. <S> You can jump on the road bike and ride the race without crashing- <S> that isn't the hard part. <S> Ride the race on your hybrid, have fun, and think about your objectives going forward.
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If you want to place as well as you can, you need to get a tri bike, practice on it a lot, know the most efficient positions for each part of the course, and shift gears smoothly and appropriately. It takes a while to get used to any new gear system. Rental agreements often include specific lines forbidding racing on the rented equipment.
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Can a 21 speed Shimano Tourney groupset get converted into a 7-speed? I currently ride a 3x7 Tourney bike, which I’ve upgraded moderately and it is riding nice. I’d like to know if I can somehow replace my 3-crankset for a simple one, and also get rid off the front shifter and its cable. <Q> Yes - note that some bikes will still need the front derailleur to help prevent the chain from falling off, which defeats the lightness goal, and only makes the bike slightly simpler. <S> You'd use the upper and lower limit screws to force the FD cage to an appropriate place, and then can remove the cable and shifter. <A> Best would be to get a crank which fit's the current bottom bracket where you can unscrew the chain rings. <S> Then it's just a simple case of getting rid of the front deraileur and shifter and be good to go. <A> Yes this is possible. <S> You'll need short chainring bolts as the middle and outer rings typically share bolts, but these are available and inexpensive. <S> You want to use the middle position for the single chainring as it aligns with the rear cassette the best. <S> You can put the large ring in the middle position if you want. <S> A tourney equipped bike likely has a square taper axle bottom bracket. <S> There are plenty of inexpensive single ring cranks available for this. <S> Look for cranks for single speed bikes, or 'track' cranks.
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Couple of options for single ring cranks: If your current cranks have removable chainrings you can take off the outer and inner rings. Yeah that's doable.
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The Effects of Widening Seat/Chainstays first time so bear with me please.I recently had to replace my rear wheel. Went to LBS and the only options available are 130mm spaced. I have a nice Specialized 1980s frame that measures 126mm. It's a steel frame so squeezing in the new wheel is no problem. However, I'm curious how this will affect the feel of the bike. By essentially widening the "stance" of the bike, will I lose some responsiveness and agility or will it feel the same? Followed up by how will this affect the tension of the shifter cables that travel along the chainstay? Thanks for your help! PS. If anyone knows where to find a 6 speed 126mm QR rear hub that I can build a wheel around (or a complete wheel) let me know. I've not had much success searching for one. Thanks again! <Q> Not sure what you mean by 'stance' of the bike, but rear wheel will not be moved relative to the bottom bracket by a perceptible amount. <S> Similarly, shift cable will not be affected, but can be adjusted anyway. <A> I'm not sure where you are located, but I believe SJS will ship worldwide. <S> Alternatively this hub may be available from a local to you supplier: <S> SJS Cycles Diacompe Hub 126mm <S> OLN <S> Spa cycles in Harrogate (UK) also offer this one in 126mm OLN spacing as well: SPA Cycles 126mm OLN Zenith Rear Hub <S> I should point out that I am using one of these hubs in the rear of a 1989 Dawes Galaxy Touring bike with 126mm OLN spacing. <A> Widening the spacing of the rear dropouts by 2mm either side will have a very minor effect on the feel of the bike. <S> I don’t expect you would notice. <S> Generally, shorter chain stays are said to increase <S> a bike’s responsiveness/agility. <S> Happy days. <S> If you source a 130mm spaced wheel and <S> you like it <S> , then you can have the frame spaced permanently (‘cold-set’) and the dropouts aligned parallel again by LBS for long-term use. <S> Any change in the rear derailleur cable length will be similarly small, at worst this would mean a small adjustment to indexing. <S> A new hub and freewheel might mean small adjustment anyway, so not a drama. <S> If you don’t know how to adjust derailleur cables this would be perfect context to learn how.
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No change in handling will result. Theoretically though, as you widen the spacing, the distance from the bottom bracket to the rear hub axle will decrease, if anything.
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Bent fork, is it replaceable? I got into an accident on my Raleigh Revenio 1.0 nearly 5 years ago. I've ridden it 400-500km since then with no problems. I don't see any damage to my top tube, down tube, or head tube. It turns out that I bent my fork, but I didn't know that until just last week. I've moved from the USA to The Netherlands recently and I my local bike shop guy says professionally he thinks it is unsafe to ride, but personally he'd ride it. I have a few questions: Can I get this replaced? My LBS guy says it's some kind of integrated system that is out of date now. Also, the bike is American and I'm in Europe. Maybe I can get a replacement more easily in the USA? How dangerous is this to ride? I have a race (triathlon with 40km bike) in 2 weeks and I'm hesitant either to switch bikes now (plus I'm kinda broke) or to use a rental for the day. I know tons about swimming and running (coached both for many years), but next to nothing about cycling, so any help will be very much appreciated. I know my bike is a 56cm frame, but beyond that I'm a novice. Thanks for any help you can provide. <Q> You have three hazards. <S> But if you are religious about inspecting the fork for cracks on a regular basis (and taking action of some sort should a crack appear) then the danger of this is low. <S> Second, having the wheel pushed back reduces your toe clearance, which can result in nasty spills if your toe hangs up on the wheel. <S> But there are many bikes designed with less clearance than yours, so <S> this is a personal choice kind of thing. <S> Third, and possibly most significant, the damage affects the delicate geometry -- the "rake" and "trail" -- of the front wheel. <S> This affects handling and stability in subtle (and not so subtle) ways. <S> But if you've been riding the damaged bike for 5 years and not noticed this you've either become accustomed to this or the effect is not strong enough to worry about. <S> It's possible you could find a damaged one to scavenge parts from, but you'd have to be sure the "donor" bike did not have front end damage. <A> Answering your first question: I did a quick search and it seems that some Raleigh Revenio have so called tapered head tube (the top bearing is then 1 1/8" and the bottom bearing is 1.5") while others should have a standard 1 1/8". <S> There are front forks for tapered head tubes <S> are to be sourced in the Netherlands for under 100 euro (carbon, just checked) and for 1 1/8" are even cheaper. <S> The replacement itself should take not more than half an hour (own experience) <S> provided that nothing else is damaged. <S> What part of the Netherlands are you located in? <S> Perhaps I can help? <S> Good luck with your triatlon! <A> Fork blades do like like they have been pushed back. <S> This effectively reduces the offset (perpendicular distance between steering axis and wheel axle), and increases the trail (how far behind where the steering axis intersects the ground the wheel contact patch is). <S> If the steering does not feel weird to you, and you are always in control of the bike <S> then it's not dangerous. <S> This will depend on how fast you are riding though, problems may show up at higher speeds, or under harder braking. <S> A bigger concern is that the aluminum fork will develop a crack and fail, so you should replace it. <S> Generic replacement forks for road bikes are available - obviously <S> it's not going to match the paint scheme but a black one should look OK. <S> Re your questions about compatibility: There should be no problem being in Europe vs. the US. <S> The vast majority of bikes and components are made in the Far East for a global market. <S> Raleigh is putatively a British brand anyway. <S> [EDIT appears I'm wrong about this, see @Mike's answer] . <S> An issue may be the headset bearings which appear to be an internal type. <S> I think this is what your mechanic is referring to. ' <S> Out of date' does not mean 'not available' though. <S> You may not even need to replace the headset bearings. <S> I'd consult with some other repair shops and get them to explain exactly what is required to replace the fork.
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First, there is some danger that the fork could fail catastrophically. There can also be problems with the headset bearings being damaged and the head tube being distorted, The head tube is not tapered so the fork very likely has a standard non-tapered 11⁄8" / 28.6mm steerer tube. The bike looks like a reasonably popular one in the US, though I can't say about the specific model. Nevertheless, disassembling and measuring all the parts gives the most accurate answer.
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How to tighten the Hollowtech II (on R2000 Claris) cranks? The owner's manual on my new bike (with the new Shimano Claris, not the old one with Octalink) asks me to do this: After the first 20 km tighten the crankset and also tighten the pedals in the crank arms. Check if crank bolts are properly tightened. Check whether left crank arm screws are tightened firmly when bottom bracket axle is integrated with right crank arm. I found many tutorials on the web they are about assembling the cranks, replacing them and they all include removing the cranks. But if I understand the manual, it specifically instructs me not to do that and leave such operation to a specialist: Important warning! No check of crank arms fastening ... may result in ... Such damaged crank arms must be replaced with new crank arms. Please contact special bike service for crank arms replacement. <Q> Park Tool's website has quite a few "fix your bike" tutorial videos. <S> You may have already seen this one: Crank Removal and Installation - Two Piece Compression Slotted (Hollowtech II, FSA) <S> I do wonder how many bike shop mechanics go to Park Tool's website and watch the videos for tips on how to work on obscure parts. <S> In this case, "how to tighten the crankset" is a necessary part of installing such a crankset. <S> For this video, that starts about the 4-minute mark. <S> In this case, all you probably need to do is get the proper Allen wrench and make sure the two clamp bolts are tight. <S> (And that doesn't mean King Kong tight...) <S> There's nothing special about doing your own bicycle maintenance - there's nothing really hard about any of it. <S> Even building your own wheels from parts is actually easy if you have the patience and can be done with just the proper spoke wrench (preferably a good butterfly one, as using some of those tiny spoke wrenches to build a wheel can be tough on the fingers). <S> In some cases, you will need special tools. <S> For a Hollowtech II crankset removal, you need something like a Shimano TL-FC16 Crankset Arm Tool to get the dust cover off. <S> (Hint - you have to loosen the two Allen bolts holding the crank <S> arm tight to get that cover out...) <A> I think you are confusing the tightness of the clamping of the crank arm onto the axle with setting the bearing preload. <S> Clamping of the crank arm onto the axle is accomplished with the two pinch bolts. <S> I believe your owners manual just wants you to make sure these two bolts are tight. <S> Ideally you would use a torque wrench to do this. <S> The bearing preload is set by the black plastic cap before tightening the pinch bolts when installing the crank arm. <S> Unless the left crank arm came loose the preload should be fine. <S> You can check for play in the axle as shown in the video. <A> If you were to loosen the bolts for any reason, you would torque check them when you tighten them up and again after the first 20 km. <S> So the manual is instructing you not to disassemble the cranks but partly because in this context you would be resetting that 20 km ‘clock’.
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I think the implication is that anytime you install these types of cranks, when you’ve ridden for 20 km you are then expected to tighten up/torque check the two pinch bolts again.
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What pressure should a tire have? I am a new bike rider. Over three months, my wheels are a little bit flat. However I am not too sure as to what pressure I should pump them back up to. Currently they show 25 PSI (172 kPa). It is a hybrid bike I use to ride to work. Is there any way I can check what the pressure should be? And what is the lowest acceptable pressure that is ok for tires? <Q> Each type and size of tire has a different pressure range. <S> The range is written or embossed right on the side of the tire. <S> The actual pressure you choose is dependent on what you are using the bike for, the road surface you ride on and your general preference. <S> A safe choice the middle of the specified pressure range. <S> Lower pressure will give a bit more comfort, higher pressure gives slightly less rolling resistance. <A> what is the lowest acceptable pressure that is ok for tires? <S> The lowest acceptable pressure for a tyre on a wheel on a bicycle varies, but will be high enough to not pinch flat on a rock or pothole by letting the rim squid through/around the rubber and hit the ground high enough to not squirm when cornering fast high enough to avoid coming off the rim high enough to stop the tyre sliding around the rim and tearing off the valve <S> For a 4" fat tyre that might be 5 PSI. <S> For a 2" MTB tyre that might be 20 PSI if tubeless or 35 PSI if tubed. <S> For a road tyre of 28mm that could be 80 PSI, or a 23mm tyre might need 100 PSI to be safe. <A> The maximum pressure will be written on the side-wall of the tyre, though it can be rather hard to find as it's just embossed. <S> For a hybrid, I'd probably just pump the tyre up to the point where there's very little give if you squeeze the sidewalls between your thumb and index finger, and not worry about PSI. <S> If you're heavy, though, you'll need higher pressures.
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Beware that too low pressure can make the inner tube susceptible to punctures caused by hitting a bump hard (known as 'pinch flats').
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BB spindle length/chainline for re-used Shimano FC-M391 chainset I'm trying to rebuild an old Univega MTB. Primary goal is to build a good or decent bike from used parts. The crankset+bb that was on the bike when I got it was really worn out. I unscrewed it and cleaned the frame carefully. I asked around and found a friend that had a Shimano FC-M391 crankset with its original BB I could get. When I installed it I just noticed that the new BB axle was ~10mm longer than the one I removed from the Univega. Unfortunately I didn't measure it but I guess it's 123mm. The original from the Univega was 110,6mm. The new crankset doesn't come close enough to the frame. From what I can see I would like to have it ~10mm closer? I think I got it to come up all the way on the BB-axle. I thought the BB axle length was specified with the crankset? I looked in the Shimano docs where it says 123mm . What width should I use for this bike? <Q> The spindle length depends on your frame and on the used crank. <S> The combination of those two will dictate your chainline which should be 47.5mm. <S> In some cases it can be 47.5-50mm ( see https://www.sheldonbrown.com/chainline.html ) <S> There are also chainlines for other types of bike, the 47.5mm are for Mountain Bikes. <S> You can measure your current chainline and then calculate the spindle length you need based on the current chainline and spindle lenghth. <S> So for example if you now got a chainline of 52.5mm and need 47.5mm <S> your BB spindle should be 10mm shorter to achieve this. <A> If the old crankset was a MTB triple, you can start by assuming the chainring offset is the same as the Acera unit. <S> So you then need a BB unit that has the same spindle length as the original. <A> Thanks for all your help. <S> I bought a 113mm BB <S> and it seems to work. <S> I couldn't measure the original crank + bb combo <S> so I measured how much space I had between the cogs and the frame and bought a bb that was shorter than the one I got before.
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As noted in @nollak's answer, spindle length required is dependent on the frame and the offset of the chainrings on the crank.
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Is it worth to get a Bianchi Caurus 909 and rebuild some parts? I'm planning to get a Bianchi Caurus 909 2nd hand for city bike and some long rides (30 km average) whenever i want to visit another city for example. The thing is if it worths to get the bike and change the gears, maybe the brakes, handlebar plus the maintenance. I've asked a bicycle guy from my city and he said it would cost something like 80 euros to clean and change its parts that i've mentioned on top. I'd like to convert this: To this: Thanks! <Q> From economical standpoint, rebuilding bicycles is almost always unreasonable. <S> For the same amount of money spent on replacement components, it is often possible to buy a new decent bicycle of the same or better level, thus saving workshop time. <S> If you do enjoy working on your bikes, restoring old things, or want to learn new skills and things, then go for it — <S> wrenching on a bike is often a rewarding experience. <A> If it’s ‘worth it’ to you depends on many things. <S> You’ll have to figure out what it will cost in terms of money and time. <S> You’ll probably have to spend time researching component compatibility, installation and adjustment. <S> You may also need to buy special tools. <S> Start by figuring out what needs replacing immediately, and what you’ll have to or want to replace eventually, and add up the cost. <S> Don’t forget things like bar tape and a new chain. <S> You should also figure out if there is anything that will be a real pain - like 27” wheels instead of 700c. <S> If you enjoy repairing and refurbishing bikes by all means go for it. <S> You will end up with a cool bike. <A> Provided you do the work yourself, used bikes almost always work out cheaper than new. <S> If you are going to rely on a bike shop to do the work needed, new (or new new) will be <S> cheaper - labour is expensive. <S> Parts can also add up very quickly, especially if buying at MRRP. <S> Shopping online, learning whats compatible with what and ordering the parts based on low priced deals can save a fortune. <S> On an older bike, the range available online my be harder to come buy in online shops, and you may be forced to pay MRRP at the LBS. <S> In summary - if your a tinkerer who loves to learn and experiment and do things yourself, an old bike will save money and get you a better bike than buying new. <S> If you are the type that gets the LBS to repair your punctures, an old bike could be buying a who lot of expensive trouble.
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If, however, money is not a deciding factor for starting a rebuild, then the answer depends on whether you like spending your time with bike tinkering, and have no other better/enjoyable things to do.
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Is it significant that my bike sometimes makes a "twang" sound when I hit a bump? I recently bought a 2016 Cannondale Synapse Carbon Disc road bike, which is working great -- however I notice that occasionally when my front wheel hits a bump (e.g. a small pothole or the lip of a driveway), the front fork (or something beneath it) goes into some sort of vibration mode and makes a noise that sounds a lot like the "twang" of a door-stopper for about a quarter-second. It's a little surprising when this happens (both due to the unexpected sound and the vibration I feel through the handlebars), but I don't observe any obvious problems other than that. My question is, is this sort of behavior normal/expected with this type of bike, or is it an indicator that something needs adjustment? (The quick-release lever seems to engaged tightly AFAICT, and there is no reflector mounted on the front spokes) <Q> I would guess these are the spokes. <S> When hitting a bump, you wheel gets compressed. <S> The harder you hit it the more. <S> When you wheel is getting compressed <S> some (Upper and lower) spokes obviously loose their tension. <S> The wheel then will pop back in it's original shape due the rest of the spokes which are streched. <S> This will bring back the tension to the compressed spokes which usually is noticeable with the "twang" noise. <S> It may be a hint that you need to tighten your spokes. <S> The looser your spokes are, the more compressed the wheel can get, which again can loosen your spokes even more. <S> This can create a downwards spiral until the spokes start breaking. <S> Look I drew a nice picture :) <A> I have a GT Grade Carbon which is designed and produced by the same corporation as your Cannondale. <S> I have the described effect on high speed braking only which is quite common problem <S> and it's easy to find information about it over the internet. <S> Moreover, this effect was one of the reasons manufacturers switched to through-axles on road bikes too, and I believe it makes sense because this vibration makes quick-release loose with time. <S> Make sure to check it more often while you have this effect unresolved. <S> I wouldn't say that I'm confident on why it happens to you during the normal operation, but some basic sense suggests that it could be something loose, online forums suggest that it could be the headset <S> and I believe it can make sense because that's the only thing keeping your fork steady. <S> I would suggest to you to run through the checks in this video, it's not as complicated as you may think: Please let us know if tightening the headset helps! <A> Pretty much any bike’s gonna ‘ring’ a bit if you hit a sharp bump hard. <S> It should not be making that noise though. <S> I’d just go over the whole bike looking for anything loose.
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Don’t forget cables, housings, spokes etc, You can try dropping the bike onto its wheels from six inches or so to see if you can replicate and locate the general area the noise is coming from. Simply check your spokes an tighten them if necessary.
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Is 7-speed for 10-speed cassette replacement possible? I have a city/touring bike with Shimano MF-TZ21 freewheel hub which is 340mm wide (I measured). I would like to change it to a 10-speed cassette 11-25 or 11-28 but I am not sure if it can fit between my chainstays (129mm). I know I would need to buy shorter hub also (and deraileurs, shifters, chain etc.). In bike service they told me (without measurements) they are not sure if new 10-speed package can fit between my chainstay. I googled 10-speed Shimano cassette dimensions but I could hardly find anything I can interpret correctly.Please help, can I fit new package in 129mm? <Q> Higher number of speed cassettes and freewheel are not wider, they have smaller sprocket spacing. <S> (11 speed requires a wider freehub body on road bikes). <S> I'm not terribly familiar with freewheels, but I would think the same principle holds. <S> However , if you have a 7 speed rear, freewheel equipped, Tourney level bike, and you want a 10 speed rear, you really want a whole different bike. <S> You'll need to replace the crankset as well as the derailleurs and shifters. <S> It will probably be cheaper and you'll get an upgrade on every component, not just the drivetrain and it will work right out of the box. <A> You have a freewheel not a freehub. <S> Therefore your wheel cannot take a cassette. <S> Instead it has to have the sort where the clicky part is part of the cogs/block/cluster. <S> While 8 speed freehubs existed, they bent axles very easily and were a technical failure. <S> If you want 10 speed on that bike, you need a new rear wheel hub, which may work out more expensive than a complete new rear wheel. <S> You also need a new shifter on the bars, a new 10 speed chain, and maybe a new derailleur especially if you get more teeth on the big cog. <S> Honestly this is a very expensive way to do it. <S> Since you enjoy riding, consider a second bike. <S> Then you have two bikes! <A> A quick search in my internet LBS returns a 10-speed freewheel that is 41.1mm wide, weights 624g and has a range between 11 and 34 cogs. <S> If your current freewheel is 34 mm check if: a) there is room for those extra 7.1mm b) your current derailleur has enough move to reach all sprockets c) <S> you can get an indexed shifter for 10 speeds. <S> Is your frame steel, aluminium or carbon? <S> The first one can be slightly set out to accommodate wider hub (you can put some spacers on the axle). <S> Making a step back with your question - what are you planning to achieve with this replacement? <S> Wider range of gears? <S> Or simply more speeds? <S> For the latter you might want to read the question <S> Modern road bike 8 spd vs 9 spd <S> - what are benefits and is it just about the speed? <S> For the former you might want to stick with 7 speed freewheel only with 13-34 range?
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To get a 10 speed rear you need to upgrade to Tiagra or Deore, depending on if you have a road or mountain style bike. 7 speed is already pushing the limits of the design, and bent axles are common. If you were talking about a cassette/freehub system, you would be able to fit a 10 speed cassette on the existing hub because the freehub body is the same width for 7 to 10 speed cassettes. Buying the bare drivetrain groupset will be expensive, require a lot of time to install, require special tools and will give you a lot of headaches trying to get it set up correctly. Go the easy route and get an upgraded bike.
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What are the causes of rear derailleur chain noise? My rear derailleur is making some noise and I'm having trouble diagnosing the cause. It seems like it's coming from the rear cogs and sounds similar to chain noise. I'm re-building my bike after an accident, so it's possible that something was bent though I don't see any gross damage to the RD. I've spent some time browsing this site and others for ideas, and have checked the following: Checked hangar alignment Lubed the rear cogs Lubed the chain Checked the b-limit setting Indexed the gears & ensured they shift well Checked for chain stretch (chain only has ~250 mi on it) Can you think of any other causes for a noisy rear derailleur? I have a video if it's helpful. EDIT: Thanks everyone for the help and suggestions! It ended up being a combination of a bent hanger and a twisted derailleur cage. I replaced the hanger with a new one which helped to reduce the noise, but there was still some prominent noise coming from the jockey wheels, mostly on the smaller cogs, and only when in the large chainring. I changed the derailleur and the noise is now gone. <Q> Check for hair, grit, etc caught up in the derailleur wheels; most likely the guide pulley wheel; remove both wheels: attach the tension wheel last after cleaning/oiling. <S> Make sure you pay attention to which wheels go where; and the direction arrow on the tension wheel. <S> A google search will show you a diagram of both wheels labelled and the turning direction of both wheels. <S> eg. <S> guide wheel is the largest wheel located nearest to the cassette. <S> Both wheels should have labels `etched' on them. <A> If you don't have an alignment tool for the hanger you could maybe use an old wheel with a threaded axle if you have one available. <S> Most often the hanger is bent towards the wheel. <S> A clear sign of this is if the gear change works well with the smaller cogs but the derailleur moves a little bit too far on the bigger cogs. <S> Because on the smaller cogs the lever of the derailleur cage is shorter and so is the influence of the misaligned hanger. <S> But on the bigger cogs the influence is bigger. <S> So if you setup the derailleur for the smaller cogs and the noise becomes louder when switching to bigger gears or maybe even changes two gears at once <S> then it's most probably a hanger which is bent to the inside. <A> On checking the hanger alignment, A, how did you check? <S> There are alignment tools for that. <S> B, Did you check both "twist" and "bend"? <S> I.E. <S> Looking from behind, is the hanger straight down, or in toward the wheel ( bike was in an accident, usually, they get bent inward ). <S> That is "bend", <S> twist would be looking from above the bike down to the ground, is the front of the hanger closer to the wheel? <S> It is hard to tell without the tool, unless the bend is severe. <S> Next, in the accident, could the rear derailleur have gotten bent itself? <A> Chances are that the derailleur cage is slightly bent or that you are using a wider chain than the optimal. <S> Chains that are used for 6 to 8 speed bikes are wider than chains used in bikes that have 9 speeds, and even wider than bikes with 10 or 11 speeds.
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The axle should fit the derailleur hanger thread.
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Shimano STEPS E8000 battery won't charge I have a STEPS E8000 bike and wanted to make some improvements, like possibility to charge from any kind of CC/CV charger (even using solar panels when grid is not available) and to charge it to 41v to improve cycle life but things went wrong after first brief charge. I charged(CC/CV) just a little from 40.3v to 40.6v when i observed that the battery level indicator is not working anymore. The battery doesn't want to start at all and the Shimano charger is just blinking when connected, meaning some kind of error. Now i have 2 options: buy a new battery or find some Shimano service but i have no ideea if Shimano fixes a battery without warranty. The second problem is that im not sure if a new battery will work wihout pairing/programming. Any thoughts why the battery(or BMS) got bricked when charging the cells directly and will a new battery work (plug'n'play)? <Q> It looks like you might have bypassed the charge controller on the pack and charged the cells directly? <S> The smarter pack controllers do a form of coulomb counting and will see anomalous or unexpected pack voltages as a risk and premptively brick. <S> But before you get to that conclusion, I’d measure the individual cell voltages and make sure they are all within 0.1 volts of each other and that none are anomalously low. <S> Balances often have a limited capacity for rebalancing and will brick a pack that is unbalanced too far. <S> Finally if you want to repair the pack, you may find a new / used pack controller part on eBay or you might be able to scavenge off an older pack. <S> But be aware some controllers do brick themselves at end of life <S> so you might be SOL anyway. <S> It’s not a huge loss. <S> You can still break the pack apart and use the 18650 cells in other projects or sell them on eBay. <A> "The second problem is that im not sure if a new battery will work wihout pairing/programming. <S> ... and will a new battery work (plug'n'play)?" <S> Yes, no problem, I've used three different batteries on my bike so far and no problem switiching between them, nor when the other batteries went back to their original bikes. <A> I looked at the Shimano protocol and they put a challenge response between the bike and the battery in order to prevent replacing the cell. <S> Looking at your picture, I see a white PCB in order to do not can follow the track of the component on the PCB. <S> By the way there is some glue on the components and connectors, that means they really don't want you to repair the battery yourself. <S> It would be helpful to see other pictures of the PCB, If you can show me the component references ? <S> Maybe if the battery is broken, I'd be interested to see the bottom of the battery PCB <A> Are you sure all connections are clean between the battery and charger? <S> I try to keep things clean and have been advised by my dealer ( Cooksons in Prestwitch). <S> Recently neither of us could see a problem so the battery was returned to Madison. <S> They found particles within the charger battery interface. <S> Magnificent service from both!
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The worst case scenario is that you bricked the controller on the pack and you can’t recover the controller.
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How to "fit in" a cycling bunch? This is a genuine request for ideas on how to be effective in not following the " Velominati " rules. How to keep cyclists of all persuasions together and be accepting of others, from leadership to newbies. The alternative: https://humancyclist.wordpress.com/2014/05/03/the-rules-rewritten-cycling/ Basically we ride, we do what we wantI ride, I do what I wantand look how I want How can we keep bunch riders together, have regular rides, and not slip into this elitist Velominati (it's not even a word)? I am after tips, DO's and DONT's on how to keep a smile and not feed into the egos in the bunch. That's pretty much it. <Q> I've heard once: if a person offers you a gift <S> and you don't accept it - it remains the property of the other person. <S> And it's the same with criticism. <S> And thus, if you engage yourself into a discussion you most likely end up in a fight over the colour of your bar tape. <S> You can use some responses to the comments on your gear (socks, bike, etc.) <S> , I've sorted them out from the least offensive: <S> if it goes about the socks and such, go " laundry day, sorry, I'll do my best to match them next time " <S> remarks on how old/ <S> outdated your equipment is can be replied with " gets me going <S> but I'd be glad to try yours if you say it's that great. <S> I know what to upgrade. " <S> general remarks can be replied with " don't worry, next time I'll go slower <S> so I stay behind you and don't fall into your field of sight " Whatever you say, don't engage into further discussion . <S> Simply don't and stand your ground - you're there for the ride and not for the looks. <S> This will most likely introduce a split in your group to those who blindly follow Velominati rules and those who, like you, want to enjoy the ride. <S> Only the time will tell if the division remains or dissolves. <S> Of course some basic rules apply concerning safety and correct gear (road bike). <S> And worst case scenario is that you become the only outsider. <S> In such case this group wasn't meant for you. <A> This is almost a question for https://interpersonal.stackexchange.com/ . <S> Any group of people has a spectrum of attitudes and social skills. <S> Just ignore and don't engage with anyone in the group that you don't like, or who acts in a way you find objectionable. <S> Hang out with the people you do like. <A> Change the riding style. <S> Either go to the mountain biking or touring/endurance riding. <S> The Rules do not apply to them: to MTB — because it originated from different historical background; to touring — because after two weeks of uninterrupted cycling nobody could possibly care how many hair you have and what color your clothes are, because everyone is covered with the same amount of (off)road dirt. <S> The touring is the most relaxed style in this regard because it is based on survival principles, and whatever allows you (and your group) to achieve the goal, is appropriate. <S> And if someone even dares to mention The Rules — just dismiss that unwise attempt: "But they are for roadies!"
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Assuming that you are not the only one hating the rules try not to get into the discussions .
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Can I fit a bigger cassette just by changing the hub and not getting a new wheel? I have an old 29er that came with a 7 speed shimano tourney groupset, can I replace that with a 9-10 speed new set, just by getting new hubs? or the wheel cant handle that setup? the frame needs to be "prepared" for that change too? <Q> Its a common misconception that cassettes with more sprockets are wider, so the hub needs to be narrower or the frame needs to be wider, but actually the sprockets are closer together. <S> 8, 9, 10 and mountain bike 11 speed cassettes are all the same width. <S> This does not mean you can convert your bike to 9 or 10 speed though. <S> TL: <S> DR - it's usually not cost effective to upgrade Tourney level bikes. <S> You would need to replace the cassette, rear derailleur, chain and shifters, very likely the crankset, front derailleur and bottom bracket too. <S> For 10 speed you would need to be at Shimano Deore. <S> If you add in the special tools required, paying someone to install it all (or making the investment in learning how to do it yourself), you will find that the cost approaches that of a new bike. <A> Depends on what type is your rear hub. <S> If it's for threaded freewheel then no, you can't - you must change the hub before putting 9/10sp splined cassette <S> Here is an example of mass hub types - Bicycle Rear Hub <A> Yes, you can. <S> You simply need to rebuild the whole wheel, as mentioned in the comments. <S> This leaves you with the old rim only. <S> It's like asking "can I replace a complete drivetrain in my 4WD car for something better? <S> " <S> Now some serious information - measure the width of your 7 speed and compare it with the 9 or 10 speed cassette you are planning to put on. <S> It may happen that the widths are not that different <S> and you can still fit the new cassette on the existing hub. <S> It goes down to the spacers between the cogwheels. <S> See my explanation here: https://bicycles.stackexchange.com/a/55668/34697 <S> Furthermore, similar question was already asked: Could I replace a hub on a wheel?
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You may be able to get a 9 or 10 speed sprocket cassette on your wheel, if you have a freehub style hub rather than an older style freewheel . Yes, you can however oftentimes it is much easier, faster and financially more convenient to simply get a new car. You might be able to reuse the spokes, maybe you will have to buy the new ones.
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Is it cheaper to mass produce a carbon frame than an aluminium frame? I've heard this comment but I have not found any information about it. Is it true? <Q> There are some videos on YouTube that show the basics of the process of making a CF frame. <S> There hundreds of individually cut sections sections of CF cloth that need to be combined together in multiple steps to give the frame strength where it is needed. <S> All the sections of CF cloth need to be combined together in moulds by hand. <S> This is where a lot of the cost comes from. <A> It's basically untrue. <S> Everything about carbon adds to the price. <A> Cheap Carbon frames may well be cheaper to build than aluminum frames, but carbon has many more failure modes that can be introduced at manufacturing, requiring much higher levels of quality control. <S> It possible to buy very cheap carbon components out of China, but how many of us choose to buy these? <S> I am happy to ride a bike made from carbon parts, but but would never consider using off brand for parts I consider critical - stems, forks, bars, frame, wheels. <S> Happy to use cheap carbon stem spacers though.
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Given that alloy framed bikes are generally cheaper than CF framed bikes, it's reasonable to conclude that an alloy frame is cheaper to produce than a CF one. The raw materials and tooling are more expensive, the process takes longer, and the work is generally regarded as more finicky and easier for things to go wrong with, leading to a higher reject rate.
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What kind of crankset is this? Can someone help me identify this crankset type? And is it possible to replace only the cranks (and their axle) without replacing the chainwheel/front derailleur? <Q> This is a cottered crank . <S> There should be no need to replace the front derailleur. <S> There is a risk that the bottom bracket shell is threade for an obsolete standard. <S> To make any guesses if that is the case, we'd need to know the brand of the bike and width of the bottom bracket shell part of frame without any parts that are screwed in. <A> To add to ojs's answer. <S> You can replace the bottom bracket and crank with a inexpensive set. <S> You just need to match the chainring tooth-counts. <S> The cheaper cranksets use a square taper axle. <S> The only problem you will encounter is selecting the correct axle length to laterally position the chainrings properly. <S> To do this you will want to know the chain-line measurement . <S> This is the distance from the centerline of the frame to the center of the mid-point between the two chainrings. <A> Looking at that bottom bracket, hopefully it uses some type of freewheel removal tool to remove the cups. <S> If not good luck finding the tool. <S> Honestly on a bike like this, I'd just replace the bike. <S> Seconds, get a bb, and a crankset with similar sized chainrings. <S> Bb spindle length should be matched to crankset you buy. <S> Chainline will be off 2mm <S> but it won't be an issue. <S> As your bike is probably 126mm rear axle spaced and more modern bikes are 130mm. <S> Third try to make it shift. <S> Replace front derailleur or chain if needed. <A> This is a bit of challenge. <S> That chainring design looks familiar, may be an old Nevar or Stronglight. <S> This appears to be French and cottered. <S> If I remember correctly, several sizes of cotters, English, French, and something else. <S> Very difficult to find, so try to find in it either France or UK. <S> Good luck. <A> What has not been said yet is that seeing the threads on the spindle (axle) <S> I'm 99.9% sure that it is a cottered bottom bracket with threadless shell. <S> Unless this frame has substantial emotional value, replacing the bottom bracket is not worth economically. <S> Nevertheless, there are square-taper sets with sealed bearings and threadless nylon cups available in Europe for about €15. <S> I've fitted one myself (with huge success until now) on my Russian-made Ural bike <S> and it's holding amazingly well. <S> The idea for me was to benefit from square-taper (in my experience less maintenance and more reliability than cotters).
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The chainrings are fixed to the crank and can not be moved to another, but you can replace the entire bottom bracket (combination of axle and bearings) and crankset. If you indeed want to fix it, first step is removing that bb. French are narrow and longer pins The bottom bracket, cups, bearings and races are most likely French spec.
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Options to move the school rucksack during the trip If to commute to school by bike, how is the school rucksack usually transported? I can see the following options: Keep it on the back. It is quite heavy, gravity center will be high and in case of falling over head it may add to the injury. Put into basket above the rear wheel. The form of the usual rucksack does not fit well to secure it from falling. Use specialized bicycle container for luggage. But the models I have used so far are time consuming to remove and not adapted at all to carry on hand when full. Are there special equipment for that? Which approaches are usually taken? <Q> I've always commuted to school (and subsequently to work) by bike, and my method was: none of the methods mentioned in the question. <S> I'm from The Netherlands, and grew well into adulthood (and lived in other countries) before I realised that arriving to school like this <S> is not the norm in most of the world. <S> I think the straps were actually attached at the axle, so it would have required some tools to remove it. <S> My backpack was usually secure from falling, although it occasionally did fall or topple to the side, then I would stop to reattach it. <S> From memory, I think that happened less than once a month in a 20 km/day round trip commute. <S> I did not own any panniers at the time. <S> I have fallen off my bike once during around nine years of commuting to school by bike, while turning on an untreated icy surface, the luggage did not add to injury. <S> Later I got some Dutch-style panniers that I also left permanently on my bike. <S> I would put my school backpack inside one side of the panniers, and take out some books to put loose on the other side to balance the weight. <S> Most of my classmates simply cycled with their rather heavy backpacks. <S> At the time there was a fashion to have the backpack extremely low, with extremely long shoulder straps. <S> Some kids would have backpacks hanging as low as their knees. <S> I remember seeing kids with their backpacks so low, that the backpack would actually rest on the rear luggage rack as they were cycling. <S> I think a pannier/backpack-combination is both a poor pannier and a poor backpack, and when it's heavy it makes for an imbalance bike too, unless you can somehow convert a single backpack into /two/ panniers? <A> I also commuted by bike to school, and used something to widen the rear rack. <S> I secured the backpack with elastic straps ( image source ) <A> There are waterproof single side panniers which attach and detach quickly, have a rectangular shape meant for A4 binders and/or a laptop and have some inside pockets meant for office supplies. <S> An example is the Ortlieb Office Bag which I got when I was still in school, to replace my school backpack. <S> It's an older model than the following picture but pretty much like it: <S> It has a padded detachable shoulder strap and a nice handle too. <S> When going on vacation it's also nice to have one bag like this, it doesn't fit as much as the usual round literal sacks but its content is much more easily accessible. <S> You get used to the imbalance, it's only really a problem when the whole bag is filled to the brim with books (like on the last day of school when bringing back all the borrowed books instead of just the ones for the day. <S> In such cases I would use two panniers for once). <S> The tires wear noticeably more on the side opposing the bag, so much that I once ran a tire backwards to get the last couple of hundred kilometers out of it <S> (it was slick by then <S> so the direction didn't matter). <S> , they are expensive but last for decades. <S> I still have that same pannier I got for school <S> and it's still my favorite everday life pannier. <S> I also tried (in the shop) <S> a convertible backpack/pannier back then <S> and it took me too long to convert back and forth, but maybe they have improved since. <S> There is also an backpack adapter for all Ortlieb bags which I want to try at some point, but haven't yet.
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I had permanently attached to my rack a set of heavy-duty luggage straps, then I would attach my backpack to this. I can very much recommend Ortlieb bags
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Will my rear wheel with an internally-geared hub shift forward when pedalling steep uphill? (I'm not a bicycle mechanic. Please excuse the incorrect terminology.) I would like to have an internal hub gear (Shimano Alfine 11) installed on my bicycle. My bicycle has a horizontal rearward-facing track fork end. Situation 1: no chain tensioner I was told that to keep the chain tense the rear wheel needs to be pull backwards and then the lock nuts tightened. I am concerned that on a steep uphill the rear wheel will shift forward, e.g. if I have a bad puncture and I need to replace the tube, then I need to make sure to tighten the lock nuts to prevent the wheel shifting forwards. Question: Is my concern valid or will the wheel never shift? Assuming the chain is worn out and starts slipping and there is no new chain available. I could re-tense the chain by loosing the lock nuts and shifting the wheel back to tense the chain. Question: Is this correct? Situation 2: with a chain tensioner In this case, I could install the rear wheel right against the front of the fork end. The chain tensioner takes care of the tension. Question: Is this correct ? Assume the chain is worn out and is slipping and there is no new chain. Question Can I adjust the chain tensioner to increase the tension on the chain, i.e. does the chain tensioner only "have one tension" or is it possible to adjust the tension of the chain tensioner? <Q> Wheels in horizontal dropouts have been reported to shift. <S> You may or may not have a problem depending on how strong you are and how well your wheel clamps in your frame. <S> There are devices that fit in horizontal dropouts that hold the wheel in place and remove the need for re-adjustment after removing the wheel, such as Surly Tugnuts <S> (example only, not a product recommendation). <S> There is no need to use a chain tensioner if you have dropouts suitable for adjusting the chain tension. <S> It will only add friction and will not stop nor deal with the the wheel moving in the dropouts. <S> Worn chains can not slip on non-derailleur drivetrains. <S> A worn chain only elongates by 0.5-0.75%. <S> When your chain becomes worn you should replace it as it will accelerate wear on the sprocket and chainring, as we'll as becoming inefficient. <A> I am concerned that on a steep uphill the rear wheel will shift forward, e.g. if I have a bad puncture and I need to replace the tube, then I need to make sure to tighten the lock nuts to prevent the wheel shifting forwards. <S> Question: Is my concern valid or will the wheel never shift? <S> Shimano specifies a tightening torque of <S> 30 - 45Nm for the axle nuts on this hub. <S> it is extremely unlikely this would happen at this clamping force. <S> Additionally, the non-turn washer is knurled. <S> Assuming the chain is worn out and starts slipping and there is no new chain available. <S> Question <S> : Is this correct? <S> Yes <S> In this case, I could install the rear wheel right against the front of the fork end. <S> The chain tensioner takes care of the tension. <S> Question: Is this correct ? <S> This is correct. <S> Sounds like you have a Surly frame? <S> very few frames have horizontal dropouts and a derailleur hanger. <S> You will have to size the chain appropriately so that the tensioner can apply tension. <S> Assume <S> the chain is worn out and is slipping <S> and there is no new chain. <S> Question <S> Can I adjust the chain tensioner to increase the tension on the chain, i.e. does the chain tensioner only "have one tension" or is it possible to adjust the tension of the chain tensioner? <S> Most chain tensioners (including Shimano and Surly) do not have a tension adjustment. <S> assuming you sized the chain properly, the tensioner should be able to tension the chain even as it 'stretches' (this term is misleading, chains don't really stretch.. although the length may change slightly over it's life) <A> You are slightly exaggerating, in my opinion. <S> Unless you cannot tighten the nuts at all. <S> First of all, make sure that you put the serrated washers between the nuts and the frame - those will keep the axle from shifting - see How to properly align the rear wheel to the bike (granny bike, single speed) . <S> If you are still afraid of the wheel shifting, those may help (it's the mysterious devices that Argenti Apparatus mentions). <S> Those are not meant for preventing the wheel from shifting in the first place but rather for assisting in setting the tension to the chain. <S> Nevertheless they help a bit anyway.
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I could re-tense the chain by loosing the lock nuts and shifting the wheel back to tense the chain.
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Why ride knobbies on a commuter? For me, riding a bike is often practical, good for my health, the environment, etc., but I ultimately ride bikes because I enjoy it. I'm curious to learn about others' decisions for riding knobby tires on their commuters, aside from practical reasons, which don't interest me. I tried it for awhile on my CX bike in NYC, and wasn't in love, but I see so many commuters setup with knobbies I can't help but wonder if there is some unexplored land of fun I've yet to experience. And yes, the 'answer' is: just try it myself again. <Q> One of my bikes, used as a commuter, is kept seriously cheap. <S> I paid as much for the bike as I've been known to spend on a decent tyre. <S> So it has the tyres it came with <S> (well, one of them, I had a slightly smoother spare in the garage for the other). <S> This bike lives outside 24/7 with a high risk of theft, and does 3km/day. <S> Looking cheap is like a third lock. <S> That's an extreme example but most people riding around town are riding cheap bikes with whatever cheap tyres some marketing person thought looked good on a bike styled like a mountain bike. <S> Some of these riders are also quite noticeable as they do daft things like running red lights. <S> And it's still much quicker than walking for the same effort. <S> That accounts for the majority of cases. <S> A few people really like gravel biking and don't like changing tyres. <S> But actually on rubbish roads and with a decent chance of going up/down kerbs even to join official bike paths, a 40+mm tyre isn't so bad, if its smoothish on the centre line <A> Rephrasing the question: why do many cyclists riding on paved surfaces use tires designed for unpaved surfaces? <A> I can think of many reasons why I used to commute on knobblies. <S> I owned 1 bike <S> and I am lazy. <S> Changing tires to slicks took longer than the time it saved with a weekend off road ride. <S> Even if I had invested in another set of wheels, I was honest with myself and admitted would probably be too lazy to swap wheeles. <S> Its just wrong to run slicks on a MTB <S> If I am riding for fitness, what does it matter if I do an hour at 25km/h or an hour at 35km if I am putting out the same power? <S> With Nobblies, as soon as you slack off, you slow down and you hear it - they keep you honest. <S> I really enjoyed catching up to slower roadies on slick carbon racers, and watch the cadence go up as the buzzing got louder. <S> Now I understand what Mosquitoes do for fun. <S> They’re a great excuse when you get passed by a faster roadie.
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Nobblies are 'tougher' - hit a pot hole or mistime a kerb jump, and you are far more likely to get away with it. I speculate that it is because many riders choose mountain bikes or near MTB-hybrids because of their practicality and comfortable riding positions, and never swap out the tires.
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How to compare an IGH (Shimano Alfine 11) with a 10 speed cassette and 3x chainwheel? I'm try to compare the gear ratio of a IGH (Shimano Alfine 11) with a 10 speed cassette + 3 chainring setup. I read Sheldon Brown's gain ratio definition . I went to Sheldon Brown's gear calculator I entered all the numbers from my bike and got this result Here is my interpretation: The first column group with heading 0.53 (low) shows the gear ratio of the 10x cassette and 3x chainwheel. Example: The number circled green is 34 / 11 = 3.1 Which to me is the gear ratio (correct me if I'm wrong). That first column group tells me the highest gear ratio is 3.8 (e.g. when going downhill), and the lowest gear ratio is 0.7 (not on the screenshot, e.g. when going steep uphill). The IGH has highest ratio 2.15 (not on the screenshot) and lowest ratio 0.53. To me that means on uphills I'll have an easier time with the IGH than with the cassette. However downhills I won't be able to go as fast with the IGH than with the cassette. Is my interpretation correct? What do the other column groups mean? Consider the column group with heading 0.68 ? Where does the number circled in red come from (because 34 / 11 not equal 4.0) ? Also where do the numbers 0.53, 0.68, 0.77 etc come from. I know they are from the Shimano specs. Are they really the gear ratios? Aren't the sizes of the single rear sprocket and the front chainwheel (that are installed on the bicycle) required to calculate the gear ratio of the IGH setup? <Q> I think you’ve told it to do an Alfine hub with all 3 chainrings and all 10 cassette sprockets, so the computer is obliging. <S> Just include one chainring and one sprocket value to get the Alfine table. <S> Then calculate another table with all 3chainrings and 10 sprockets but no Alfine <S> You’ll get things more like this: <S> I put in random values (32,17) which give the Alfine something like the range of the 3x10 setup Edit: a gain ratio of 1.9 may/will feel nothing like a gain ratio of 1.2 when you're climbing, so keep playing around with numbers for the IGH chainwheel and sprocket <A> There are really two things to consider: can you get all the gear range you desire and what is the spacing between the gears? <S> The Alfine has a range of just over a factor 4 from top to bottom and you can put that range anywhere you want by choosing the gears you put on it. <S> The cassette you cite has a range of 3.3 all by itself and coupling it to any reasonable front triple will give a much wider range, say a factor 5. <S> Do you need that range? <S> I ride a 2x10 setup with 50/34 front and 12/30 rear which gives a range of 3.67. <S> I don't miss a 50-11 combo which would increase my range. <S> I might like a little lower gear at the bottom, but it hasn't been enough of a priority to do anything about. <S> That would also give about a factor 4 range. <S> Considering the overlap of the two chain rings I have effectively 13 different gears, so my spacing is on average closer than the Alfine. <S> That hides the fact that some gaps are larger than others. <S> In my cassette the gears go 14-15-17. <S> The change from a one tooth gap to a two tooth gap is noticeable. <S> The Alfine is more regularly spaced because they use so many more teeth that you can get the ratios desired. <S> They are about a 13% increase for each gear which is almost as much as my 15/17 transition. <S> I believe I would find the Alfine quite acceptable even though the gaps are a little large. <S> If you need the range of the triple plus 11/36 I suspect you would be unhappy with the Alfine. <S> You will be running out of gears at one end, the other, or both. <A> To answer the questions properly The 34/11=3.1 is a red herring. <S> The 3.1 is the Gain Ratio, the whole ratio for each mm the pedal turns to each mm the bike moves. <S> It's just coincidental that 34/11 is 3.1, resulting from the table doing the calculations effectively for a bike with the IGH strapped to the derailleur system. <S> The next interpretation is more like it, the higher the gain ratio, basically the harder the gear. <S> Lower numbers give an easier time up hill. <S> It's just that the numbers aren't correct yet. <S> The 0.53, 0.68 numbers are multipliers for each of the IGH gears, think of them as gears 1 thru 11 for the Alfine. <S> In the IGH table you'll see eleven of these headers, and one gain ratio for each. <S> The gain ratio circled in red is the gain ratio if you had gear two of the Alfine selected (0.68) and the 34/11 selected on the derailleur. <S> At the same time. <S> Finalement, you do indeed need to specify the chain wheel and sprocket for the Alfine hub, putting their single values in to the calculator to make a separate table.
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You’ll need to pick your own chainring and sprocket values for the Alfine, point being you can customise these to get the gearing you want. At the low end, small changes in gain ratio make for significant perceived differences, i.e. when you're running out of gears fast for that climb!
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Bottom bracket maintenance - is it a thing? Previously when I've had annoying noises from my bottom bracket I've simply discarded it and bought a (cheap) new one. But the last time I replaced it I got a great offer and splashed out a little bit on a Hope Road Ceramic Bottom Bracket . A couple of years on (but only 2,000 miles later) I'm getting noises out of it when I pedal. Due to injury it has sat around for a long time while I recuperated. I'm trying to avoid replacing the bottom bracket if I can. I don't need help diagnosing the source of the noise. Please assume my diagnosis is correct that the noise is from the bottom bracket - ball bearings or any other part of it including it's fitting to the frame What I'm trying to understand is: Is there some maintenance (clean and re-grease?) that I should have been doing but missed? Beyond cleaning it externally I've done nothing to the BB Does the fact that it's ceramic make a difference to question 1? Are the ball bearings generally a sealed unit or is it possible to open, clean and re-grease them? My "bike mechanic" skills are self taught since I was a teenager. Naturally there's things I find I should have been servicing all along or monitoring but simply never knew I had to (for example rim-wear). <Q> To the bearings themselves, not really. <S> It's possible to pull theseals and clean/re-grease the bearings while they're stillinstalled, but this isn't something it's expected anyone's going toactually do. <S> (The one you have I believe has bearing seals that arepretty easy to get to, making this easier to do if you want it. <S> Shimano Hollowtech BBs have the bearings covered by a plastic "tophat" seal that's not intended to be removed and re-installed, andusually can't be without ruining it.) <S> For all external cranks, it's pretty common to encounter noises thatcan only be remedied by cleaning and greasing the spindle interface. <S> That might be considered regular maintenance. <S> No. <S> The nature of external BBs is that you won't be able to remove one side's seal, which makes the process more difficult but not impossible. <S> As mentioned above, many external BBs have difficult or impossible to remove parts in the way of the bearing cartridges themselves, and doing anything with the bearing <S> isn't really practical if this is the case. <S> Another thing that bears mentioning in this conversation is that many Hollowtech 2 compatible external cups can have their cartridge bearings driven out and replaced. <S> Enduro and Phil both make presses just for this. <S> What replacement bearing and seals are appropriate depend on the BB. <A> Bottom bracket maintenance - is it a thing? <S> Yes, on open bearing BB. <S> This kind of BB's usually have two indidual cups(threaded) with bearings and a spacer to pinch the bearings. <S> Others are just a plain sealed unit and is composed of two parts. <S> The BB and a threaded ring that goes on the other side for the whole thing to rest evenly. <S> If broken just buy a new one, there is nothing you can do here. <S> Onto your case Hope Road Ceramic Bottom Bracket looks like the first sealed BB I've described. <S> You will need some sort of jig to press out your bearings, then get a caliper and messure the outside diametre, inside diametre and thickness of the bearing. <S> Even better if you get the SKU of the bearing or the model number. <S> Then go to a SKF Store(or something like that where you can buy bearings by size) and ask for your bearing. <S> Then you will need to reverse the process, make sure you press the bearings parallel to the bottom of the cup. <S> I used to have a Oddisey Euro BB with two bearings on each side, for Profile <S> Dj cranks that came with an American BB. <S> The Oddisey BB was just right for the job, but the bearing kept blowing up because the spacer wasn't long enough. <S> Hope <S> this works for ya. <A> Most modern 'unit' bottom bracket bearings such as the Hope BB you have are not meant to be disassembled or serviced. <S> Some BB models can be re-greased by carefully popping off the plastic seals. <S> I've done this on a Shimano Ultegra Hollowtech BB.
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On sealed bearing BB, depending on how the unit is constructed you may get away by swapping bearings. In general, all cartridge bearings with rubber seals can have the seals carefully removed, which is something of a skill in and of itself, be cleaned with solvent, rinse, blown dry with air, and re-lubricated. Tolerances in this kind of pieces is tight, if isn't pressed right the axle won't fit, or your new bearing will blow out soon.
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Replacing an FSA chainring I would like to replace my chainring for a bigger one. I looked up my bike specs and it comes with a FSA CK-316BT, KSS, 42T chainring. I couldn't find any information about this, so I don't know how to buy a bigger chainring. Here is a picture of what I am trying to replace, I am trying to replace only the chainring and not the whole chainset. My question is, what type of chainring can I use to replace my current one? <Q> The main limiting factor is chainstay clearance. <S> If your chainrings touch the chainstay it will wear and weaken and eventually fail. <S> Do this first. <S> Once you have that info, get onto Sheldon's gear calculator https://www.sheldonbrown.com/gear-calc.html and play about with the numbers. <S> Will changing from 42 tooth to your maximum tooth give enough difference to notice? <S> Finally, print this PDF <S> https://cdn.shopify.com/s/files/1/0230/9291/files/BCD_finder_tool_v2.pdf <S> in 1:1 scaling, then put your chainring directly on it and see which BCD matches. <S> Note that 102 and 104 are very close as are 94 and 96. <S> Armed with those numbers <S> then you can go shopping. <S> Make sure you fit a new chain <S> (it needs more links anyway) and a new cassette. <A> The only thing I can find for this crankset is the triple version of it. <S> See: http://www.chainreactioncycles.com/de/de/fsa-ck-316ttt-alu-kurbelgarnitur/rp-prod151698 <S> The Bolt circle is stated as 104mm but as you got a 4-bolt crankset you can easily measre the diameter by measuring how much apart are the centers of two diagonal bolts. <S> Then you can just buy a new chainring for this diameter and change it. <A> I've searched for your crankset and found a replacement chainring: <S> Now, this specific chainring is 40T <S> so no use to you. <S> However, it tells us that it is <S> 104mm <S> BCD <S> (bolt circle diameter) <S> - check yours if it says the same. <S> Once you have the BCD measurement you check that it is <S> 4 bolt <S> and basically it's all you need to know to find a chainring that fits your crankset.
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So the first thing is google your bike frame and see what maximum size chainring its rated for.
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Do I need a new tire pump or can I fix my old one? My old bike pump psi gage shows a different pressure than my newer hand held tire gauge. Is there a way to fix the pump or do I need a new one? <Q> You're not going to be able to fix something like a pump: you won't be able to buy spare parts for it and, even if you could, you could probably only install them using the manufacturer's tooling. <S> However, the fact that your pump and pressure gauge disagree doesn't tell you which one is wrong. <S> Maybe your pump really is old and worn out. <S> If your two devices each measure in a consistent way (e.g., one always reads 10psi lower than the other), then just learn the translation between them. <S> Assuming you're not running at close to the maximum pressure of your tyres, it doesn't really matter if you inflate to 80psi or 90 psi, as long as the results are comfortable to you. <S> If you're happy with the state of your tyres when you pump them up to a certain pressure as measured by your pump, then keep doing that and just be aware of the different number your pressure gauge will tell you. <S> It doesn't matter if they're not real pounds per square inch (or bar or whatever scale you prefer). <S> Can you borrow a pump or gauge from somebody else? <S> Your local bike shop, for example, probably has a pump they'll let you use. <A> If the older pump reading incorrectly compared to the pressure gauge by a small, repeatable percentage or fixed error, you can just translate the incorrect reading. <S> For instance, of you want to run 70 psi, but the pump reads 65 at the pressure, just pump to 65psi as read on the pump gauge. <A> As already mentioned the pressure gauges of these pumps show often wrong values. <S> Friends and I have pumps for tubeless tires which are not cheap - and even some of those are quite off. <S> So we often use these special electronic bicycle tire pressure gauges. <S> E.g. from Topeak or Schwalbe. <S> But I'm not a fan of those. <S> I bent the thin threaded rod of some presta valves with the Topeak and my Schwalbe soon had an electronic issue. <S> So more important as the absolute value is the pressure you want to have. <S> As long as the value is consistent it should be ok. <S> If you want to know which pump is more accurate you can compare it with other pumps - maybe from friends.
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Maybe your trusty old pump is actually right and your new gauge is inaccurate. If you want to decide which one is wrong (and it might even be both!), you'll need to use multiple devices.
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Adjusting derailleur with bike upside down, is it ok? I need to adjust the derailleur on my bike, I don't have a bike stand. I have three options for pedaling while adjusting the the derailleur. Turn the bike upside down, balancing on the handlebars and seat. Tip it up on the kick stand Lay it completely on its side (if no kickstand) Upside down is easiest, but it seems like that might not be the best choice. Is it ok to adjust the derailleur when the bike is upside down? Is one method clearly better then the others? <Q> Turning it upside down seems to make the most sense, assuming it can be easily balanced. <S> Derailleurs work by spring and cable tension, not gravity <S> , so there should be no problem with working on it with the bike upside down. <S> Also, if your bike has disc brakes, you should check out this post about potential risks of inverting the hydraulics. <A> It's not ideal -- gravity on the chain slightly affects tension and the way the chain "wraps" the cogs. <S> An alternative is to use a rope or some such to hang the bike from overhead rafters (if in a garage or unfinished basement). <S> It used to be that you could get a sort of very simple "bipod" service stand that sat under the bottom bracket and held the rear wheel elevated, but likely these no longer work with many "modern" frame designs, and I can't find the via Google. <S> Folding bike service stands are available for $30-$80, however (though you need to pick a style that will work with your frame). <A> Fourth option: keep the bike upright and lift the rear wheel when you need to spin the pedals. <S> There is no need to keep the wheels off the ground while adjusting the derailleur.
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I pretty routinely will invert my bike when working on it, as I also don't have a workstand, and it's never caused problems before. Adjusting the cable tension at center of the cassette and limit screws at both ends should be all that is needed, and that can be done by visually aligning the derailleur pulleys and cassette cogs. You probably can get a good rough adjustment but not "fine tuning". The only issue you're likely to have is reaching the shifters (assuming they're bar-mounted).
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Should tire pressure be equalized or slightly offset? I am wondering wether I should match the recommended PSI of both my tires (equalized) or if I should have the front tire slightly more deflated than the back or vice versa (offset). Are there occasions where front and back tire pressure is slightly and preferably modified, such as a pro cyclist preparing a road bike for a time trial in comparison to a mountain bike for difficult terrain. <Q> Tires usually have a inflation pressure range, or maximum pressure specification rather than ab absolute recommended pressure. <S> The pressure you should be using depends on how much you weigh, the surfaces you are riding on and your preference for ride comfort. <S> Similarly there does not seem to be any definite guidance for different front and rear pressure other than the front should be a little lower because most riders have a rear weight distribution bias. <S> Personally, I ride a drop bar bike with a moderately relaxed position so I run the front about 10-15% lower than the rear. <A> I always put near maximum pressure for the rear tire, because it will support most of the weight of me and my bike. <S> For the front tire, I put slightly less pressure. <S> This will improve handling because less pressure will make the tire can dampening the rough terrain. <A> Because there's (usually) more weight on your rear wheel than your front, you want to run your rear tire at higher pressure to get an equal amount of "drop" (tire deformation) on both of them. <S> One theory is that you should aim for 15% vertical deformation. <S> Here's a calculator that can help .
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Unfortunately there is no way to definitely determine what you tire optimum tire pressure should be, but you can experiment with different pressures.
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Finding the correct bike for short tours and daily commutes I am looking for a new bike after my current one has started to fall apart mostly. As a disclaimer upfront: I have very little knowledge on bikes. For my current bike I did very minor repairs myself (fasten lose screws, etc.), for everything beyond that I mostly went to a shop or asked friends. I am looking for a new bike to replace my - as mentioned before - falling apart old one. My constraints are mostly on the budget as I am not in a position to spend more than around 300€ on the bike - which I know is a rather tight budget. I will be using the bike for two things mainly: Daily commutes to the train station from home. This is a short 5 minute ride that however includes going up a quite steep hill. This for me was a point that ruled out a Single-Speed. Not completely sure here though. Short tours of up to 20km (~12.5 miles). 80% road. 20% dirt/forest road. Nothing to steep, it's mostly flat around here. I would say >95% flat. The other is bridges, etc. so rather short slopes. With these things in mind I considered to go for a City Bike. My current one also is a city bike and I think that I don't really need suspension, etc. However I might be wrong here as I never tried suspension before. I also considered buying a used bike - however my problem here is that I am not sure what to look for here, to see if I buy something usable, or something that will fall apart after a couple months. So to conclude and formulate a question: For my beforementioned budget and use-cases what would be a good bike-type or specific bike to look at and where should I look for it? <Q> Consider repairing your current bicycle if you are happy with it. <S> Especially if the frame and/or wheels are of high quality and still in good shape. <S> For <300€ you can only get a very cheap entry level bicycle. <S> The same money will easily get you a pair of good tires, shifters, cables, chain, saddle, pedals, stem and handlebar to repair or upgrade your current bike. <S> If you really want a new bicycle, I’d personally go for something less sedate than a city bike. <S> Go for a hybrid, trekking bike or an MTB with rigid fork (i.e. without suspension). <S> Avoid cheap suspension forks like the plague. <A> Keep it simple, no fancy stuff, no suspension, maybe look for a 1X system (if that is possible at that price range) <S> Have it fit when you buy it <S> so you are comfortable riding it. <S> Get a good lock if you leave it at the train station. <A> Where should I look for it? <S> More and more places have bicycle recycling projects where donated bikes are refurbished by volunteers or students (or inmates) and sold on. <S> The quality is high because they sell on the best ones, fully refurbed, but the prices are low because the bikes are donated and the labour is cheap! <S> See if you can find something similar near to you. <S> It’s better value than buying new, and takes the risk and hassle out of buying second hand. <A> For my beforementioned budget and use-cases what would be a good bike-type or specific bike to look at and where should I look for it? <S> Go to a garage sale for bikes. <S> You will probably find a good bike, which was not used heavy and was standing most of the time in someone's garage, so they are in pretty good shape and you do not have to repair the whole bike. <S> You can get there bikes for around 50-100€, get a new chain, get new brake pads <S> and you are ready to go. <S> In the best case, the bike type you should be looking for is an "old school" MTB-bike, which has a steel frame, solid wheels and good shifting components. <S> so you will have little repair and maintaining.
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Repairing your current bicycle also makes sense if you plan to leave it at the train station since an old bicycle (with a good lock) is probably much less likely to get stolen than a brand new one (even if it’s cheap). Get an entry level hybrid bike from a bike shop if possible.
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Remove old non-indexed levers for gear changing to make "fixed" speed bike? I recently got an old bicycle for the sole purpose of using it on a trainer. It has old non-indexed levers for gear changing and they don't seem to work OK. The front one slips into lower after a while, and the rear one is now "locked" since it's plastic, I don't want to force it and break it. I don't want to invest much into this bike, it was already more than I was planning to spend on it. I was thinking to remove them and fix the derailleurs on a specific gear ratio. I would like to be able to adjust the rear one, but wouldn't mind if the process is somewhat cumbersome (ie: requires tools). Is this possible? What would be the best path to do it? Some pictures for clarification: Shifters: Front derailleur: Rear derailleur: There doesn't seem to be any barrel adjuster on the derailleur side, just on the shifters. <Q> If I understand correctly you have slipping shifting levers that let the derailleurs move without your intervening. <S> A non-indexed shifter slips because the friction setting is too low. <S> Friction of the lever is easily adjusted by a screw at the side of the lever. <S> If it still slips after tightening you'll unscrew the thing taking care to remember the correct order of items when is comes apart. <S> (Take a photo maybe to assist your memory.) <S> Then clean the bits to remove any grease and reassemble. <S> It usually helps. <S> At least it did in the old days before indexed gears. <A> The simplest method I can think of is to put the shifters into the position with the least cable tension (normally the small ring at the front as well as the rear) and then undo the cable from the derailleur. <S> Next, move the derailleur into the gear you want and tighten the cable in this new position. <S> A bit more detail: <S> It might need two people. <S> With the bike off the ground turn the pedals and push the rear derailleur into position and have it held there. <S> Be careful with your fingers near the moving parts! <S> Stop the wheel and tighten the cable. <S> Finally use the barrel adjuster to index the gear. <S> Make sure the lower limit screw will prevent the chain ever going into the spokes, but it already should be doing that job. <S> It would be very short and doesn't need to go through any housing. <S> That would be locked in, but you could change the gear without shortening the chain, by adjusting the cable again. <S> This would work better if the shifter proves not to be reliable for the above method. <A> Yes, it is possible. <S> The actions needed would be: remove rear wheel (you need suitable wrench unless you have quick-release axle) <S> remove chain (you need a chain breaker unless you can find a master link and disengage it) remove both front and rear derailleurs (most likely Phillips head <S> screwdriver <S> is the tool you need, perhaps suitable <S> allen key or a wrench ) <S> remove derailleur cables and shifters ( <S> again, Phillips head screwdriver, allen key or a wrench, depending on how the shifters were mounted) <S> put back the rear wheel put the chain back on the desired chainring (front) and sprocket (rear), measure how long it needs to be, using the chain breaker set the correct length and affix the chain <S> tension the chain by readjusting the rear wheel <S> This way you have converted your bike into a semi-single speed the cheapest way possible. <S> And you won't be carrying the weight of the parts you are not using. <S> If you want to go further in reducing weight you may replace the freewheel/cassette with a single-speed freewheel (you need freewheel remover tool ) and unused front chainrings (you need crank <S> remover and most likely chainring nut wrench ). <A> The really quick and dirty method (after removing the shift levers) would be to use a vise-grip plier and pinch the cable at the required position while it's routed through a cable brazing on the frame. <S> That enables relatively quick gear changes although the cable will get mangled over time. <S> Another disadvantage is that you have a plier hanging from the bike <S> and it might get in the way if you can't find a suitable spot. <S> Another quick method would be to tie a knot in the cable instead of using a plier but this makes it a little more difficult to accurately set the derailleur. <S> These solutions are the ones where cost is nil. <S> Considering the bike won't even move as it's on a trainer, the plier method isn't that out of place. <A> Your rear derailleur has upper and lower limit screws (so does the front), which will usually be either on the "knuckle" at the back of the derailleur or on the outer side plate. <S> These limit the derailleur's travel. <S> Because the derailleur is sprung, you really only need to worry about the low-limit screw; the spring will hold it against the limit. <S> Depending on what gear you want, you may not get enough range out of the limit screw, but that's where I'd start. <S> All you'll need is a screwdriver.
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The other tweak for the rear derailleur is to remove the inner cable and insert it directly into the derailleur and tighten it off in the gear you want.
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Rear wheel not straight because of worn out dropout? I noticed that my rear wheel wasn't straight and even after realignment it wouldn't stay straight. After some investigation I noticed that my rear dropout appears to be worn out: Is this the problem? What is the cause? Is this normal for a bike that is a little less than 2 years old? Is there any repair option aside from changing the frame? The quick release was bent and replaced some months ago. <Q> This almost exclusively happens because of external cam quick release skewers not clamping the wheel tight enough. <S> Bike manufacturers love them because they're light, cheap, work fine most of the time, and nobody ever questions them when buying a bike. <S> But they never have as much clamping force as internal cam types, and the problem is exacerbated once they're weathered and worn. <S> There are some out there these days coming on some bikes that barely work or don't work. <S> I know it sounds conspiratorial, but it's sadly true. <S> Another possible issue in the same vein is wingnutting down the skewer instead of properly clamping it. <S> You could try some metal filler on the frame plus a good skewer, like any Shimano. <S> Glob the filler on more than needed and then use files once it hardens to take off the excess and recreate the axle groove. <S> The upshot here is that nice skewers put on so much clamping force that the frame isn't going to receive the kind of stress that caused this. <S> This is a little bit of an experimental solution so I wouldn't expect a shop to do it. <A> That's not normal for a two year old bike, even if you are doing a lot of miles on it. <S> Dropouts do not normally wear because the axle does not move or rotate in them, so there is something else going on that has caused this. <S> As @Daniel R Hicks said in a comment the bearing might be causing the axle to rotate or the wheel was allowed to move around in the frame. <S> To check the wheel bearings, simply rotate the axle in the wheel by hand, if there is any resistance, roughness or 'notchiness' there is a bad bearing. <A> Got a similar issue but it’s a carbon frame... <S> I picked up used on trade. <S> I’m going to give some filler a run as I can’t justify scrapping a frame for some wear.
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There's a certain bike model I've been dealing with where the skewers just go in the trash, because the resting spot of the cam produces so little clamping force that using the front brake at any speed readily shifts the axle around.
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Is it practical to switch from tubeless to tubes every few weeks? Part of the allure of a gravel/cyclocross bike has been the possibly of having a "do it all" setup. I recently purchased a gravel bike with 38c tubeless tires on it, and I also have a set of 30c tubed/clinchers. I don't have any experience with tubeless but from what I've read they seemingly are a bit tricky to get setup compared to a clincher. If I have the right equipment (air compressor, sealant, levers), how practical is it to switch between tubeless and tubed depending on the terrain I plan to cover that week? Ideally one complete swap every month or so, tubeless knobbies for most training (16mph/25kph) and tubed slicks for events (20mph/32kph). <Q> If you value your time at US\$20 an hour or higher, you’ll find you’ll quickly benefit by just getting a spare set of wheels, leaving the tires permanently mounted, and swapping wheel sets as needed. <S> Otherwise, you have to clean sealant from the tubeless rims which make them a pain and buying a new bottle of sealant every now and again is going to start adding up. <S> You can often find a suitable set of wheels by buying a used donor bike. <S> Just make sure they’re true. <A> I have changed a number of tubeless tires now and the other answers are on point that generally this should be avoided, and if possible run either more than one wheel set, choose a more general setup, or stick with tubes if you need to change tires frequently. <S> The initial tubeless tire setup can go quickly if you have the right tools and a bit of practice, so this isn’t the barrier, rather it’s the tire and rim cleanup after a tire removal that is the main drawback to frequent tire swaps. <S> By far getting solidified sealant off the tire bead is the the hardest part, especially if this is not done immediately after removal (i.e., you are in a hurry to mount the new tire and get riding). <S> The longer you leave the task the harder the sealant becomes and the harder it is to remove. <S> At minimum you need 30 minutes for this task, longer for tires that have been mounted for a long time. <S> Plus after a couple tire removals and clean ups you will find peeling off the dried sealant can actually start to damage the tire bead surface. <S> At some point the damage could inhibit the ability of the tire to form an air tight seal against the rim. <S> Also in the removal process the tubeless tape can also get dislodged as the tire bead can often get stuck to the tape edge. <S> This means having to re-tape the rim which costs time and money as tubeless tape is not a commodity item. <S> Finally, sealant loss happens but is less of an issue. <S> If you are careful most of it can be sucked up and transferred to the new tire. <S> All of the above mentioned issues are really noticeable the longer <S> the tubeless tire has been installed. <S> The cleanup might go quickly if the tire is removed within a short time of installation (I.e., a couple days), but I haven’t tested this out yet. <A> I don't think I'd want to be taking off tubeless tire set up as tubeless with sealant once a month then reinstalling then later. <S> Or go for a dual purpose tubeless 38mm tire with a low profile tread.
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You could run the wider tubeless tires with tubes in them to make the swap easier.
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6-bolt vs centre-lock: pros and cons? I am having a new set of wheels built, and am trying to decide on whether to go with 6-bolt or centre-lock rotor interface. What are the pros and cons of the two systems? <Q> Centerlock largely exists because since the beginning of modern disc brakes for bikes, Shimano has more or less alone had a weird cautionary take on the physics of rotor bolts theoretically being able to loosen in the six-bolt design. <S> That's why their six-bolt rotors have always come with various retention systems for the bolts that nobody else bothers with. <S> Centerlock doesn't accomplish anything special and doesn't allow for lighter hubs or rotors (at least in a meaningful sense). <S> Shimano rotors are excellent so it's not like you're trapped if you have centerlock hubs, but you do have fewer options, and centerlock rotors are inherently more expensive at the low end because they can't just be flat pieces of steel. <S> Centerlock has the disadvantage that carrying a lockring tool plus something to turn it isn't practical, so the best you can do if you severely bend a rotor on a ride is undo the caliper mounting bolts and try to hang the caliper out of the way, which is awkward. <S> Even though the risk here is small and theoretical, it's enough of a potential day ruiner that given centerlock has little to no functional advantage, there's an argument to avoid it if all else is equal. <S> The catch is that all else is often not equal, because Shimano hubs are some of the best value choices. <S> Six-bolt does have the disadvantage that bolts getting seized, heads getting stripped, and/or hub threads getting damaged are all things that happen sometimes, whereas centerlock tends to be free from any such problems. <S> Having one big high-torque fastener does create a more reliable interface in that sense. <S> But it's a pretty fringe concern; six-bolt is perfectly robust and very few people will ever have to deal a seized rotor bolt. <S> However, in all fairness it can be a difficult enough problem to deal with when it does happen that centerlock usually looks pretty good by the second hour in. <A> Advantages of <S> 6-bolt: <S> Not being patented by Shimano means more vendors offer compatible wheels/disks. <S> Torx bolts require a smaller tool which is often included in many multi-tools so one can always have one on the road. <S> Advantages of Centerlock: <S> Faster installation and removal with a cassette tool <S> ; no need to fiddle with 6 separate bolts <S> No need to have an extra tool, use the same cassette removal tool. <A> A couple more pros of centre lock: <S> Finned rotors One big difference is that you can't get the finned Shimano Ice-Tech rotors used on the road bike groupsets in a 6-bolt configuration. <S> E.g: <S> or I've had brake fade on my Shimano RS685/785 <S> set up on descents in Wales and wanted to try the finned rotors, but my hubs are 6-bolt. <S> You can make a centre lock rotor take a 6 bolt rotor, but not the other way round <S> But, I'd be slightly wary of this approach, because any misalignment or opportunities for vibration in a disc brake setup can cause brake squealing or shudder, and while I'm sure Shimano have tested these adaptors very well, it's a fair engineering assumption that the more interfaces and separate parts there are the more chances for misalignment there are. <S> For me, I'd go 6 bolt on a mountain bike, because of the wider availability of 6 bolt rotors and the trail-side repairability, but centre locks on a road bike for the increased cooling and because they look a bit neater next to the more delicate road bike forks/chainstays (that last reason is subjective!). <A> One disadvantage of 6 bolt is that you can torque one side just a bit more than the other which can cause the rotor to be just a bit warped. <S> Center-lock torques evenly by design <S> so there’s no risk. <A> If you’ve ever stripped a torx bolt on a 6-bolt, you will have your answer for why people run centerlock. <S> I will add a small disadvantage to centerlock is boost conversion on the rear. <S> MRP sells kits for the front that use a caliper adapter to offset the rotor on the front, but nobody sells conversions for centerlock rears. <S> You could in theory convert it to 6-bolt and then use the boost adapters, but 2 adapter kits is where I draw the line and sell my sweet DT 240. <A> Adding to existing answers ... <S> 6 bolt rotors can be shimmed to make rotors on two different wheels fit in the calipers without having to re-align. <S> That's not possible on center-lock hubs.
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This is pro and a con: Shimano do an adaptor to run 6 bolt rotors on a centre-lock hub (SM-RTAD05), which is great for choice.
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Securing bikes while on a car hitch mount I've recently come into ownership of two very nice bikes. I live in an okay area, so I haven't had to worry about bike security very often. We do, however, often take our bikes to less than savory areas - we have a Thule T2 Pro and often stop for lunch ~wherever~. What is the most reasonable way to secure our bikes from theft? I understand that no security is perfect. (If you see my profile, most of my rep is form Security.SE /humblebrag) Presently we do this - this is assuming a worst case, run down terrible area, with a bike chop shop next door to where we park, etc etc. 1) Avoid parking in such areas. 2) Stay with the bikes if at all possible. 3) Bikes are attached to the Thule T2 Pro using the built in cable locks - it connects the front wheel and frame to the rack. The T2 Pro can be firmly attached to the trailer hitch using an expansion screw included in the design of the rack. We are also considering adding the following: 1) A cable lock threaded through the seat, frame, and rear wheel, to complement the front cable. 2) Locking the bikes together using a flexible plate-link lock. Neither of these are absurdly harder to implement, and avoid some, but not all, piece-meal theft. EDIT: The T2 can be attached to the car in such a way that it can't be removed without the key, or spending some time 'hacking' the locking mechanism in one way or another. This post originally didn't say that and some comments will be confusing due to this. <Q> My preference for my hitch rack security is to use a 5 foot Schlage 999478 High Security Chain with Cinch Ring to pass through the frame(s) and use with a long kryptonite evolution U-lock to secure the chain and my bikes to my hitch rack, which is secured to my car with a locking hitch pin. <S> I figure this way, <S> if anyone wants to steal my fancy mountain bike, they at least probably need power tools to easily steal my bike. <S> I prefer this method so I can more safely leave my bikes unattended for short periods while on road trips or during after ride beer stops. <S> My opinion is a cable lock is about as good of security as a strong rope. <S> Any yahoo can buy a pair of wire cutters at a dollar store for $3 and steal your bike in a minute or so if you rely only on cables. <S> However, the folding plate lock is a bit higher security. <S> I also use one of these on my commuter and would trust it for a medium level of security where I'm leaving the bike unattended for a bit. <S> Maybe not in NYC, but in the smaller city I'm from <S> , I trust it about as much as a U-lock. <A> You don't say how the rack is attached to the hitch such that it's removable, but if there's any kind of bolt, even a hand-operated screw, you could replace that with something more secure. <S> Anti tamper torx bolts are avaliable quite large, and while it's not hard to get the drivers, it's also not common to carry them. <S> When I've got bikes on the back of my van, I have a cable lock at all times (it's an adjustable one <S> so acts as an extra strap). <S> For long stops or in iffy areas I D-lock the bikes together, but I'm prone to forgetting to remove it <S> and then it bangs around. <S> My rack is aluminium tube and would take seconds to cut with a hacksaw, but the lowest point of the bikes is 4' off the ground so an unwise thief would end up underneath 2 bikes and half a rack if they tried cutting. <S> It's only fabric and elastic/straps but even assuming someone was prepared to slash it, that's still extra delay and hassle, before they even find out what's inside. <S> The main purpose of the cover is to protect the bikes from rain/spray and keep accessories safe. <S> All these are delaying tactics really, and you should still try to keep them in sight except for brief periods, assuming they look valuable. <S> One thing that's more than a delaying tactic is to reverse the vehicle until it's almost against a wall, fence, or hedge (even into the latter). <S> My van is oversized for much of the parking I use so doing this also protects against people driving into sticking out bikes, and keeps the vanfrom getting in people's way. <S> If you have a proper (police-backed) security marking scheme in your country, it's worth doing. <S> Obvious markings are a further permanent deterrent. <S> As they're e-bikes, taking the battery away and putting it inside the car (even out of sight) makes them much less desirable (and slow to ride off on). <S> Of the 2 e-bikes I've used, one had a removable battery using a key; the same key was required to start the motor, so don't leave it near the bike <A> A web search will turn up various brands (or there are a few mentioned in this article), some simply sound a loud alarm whilst others have the ability to notify you via your smartphone if they detect that your bike is being tampered with. <S> This should be appropriate for your requirements, i.e. where you're no more than a few minutes away from your bikes - it would be rather less useful if you planned to leave your bikes and wander round a big city for a few hours.
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I also will incorporate a separate cable lock to secure my wheels (I just use a loop style and thread it through the ulock as well). I also have a cover over mine. Another approach may be to use some sort of bike alarm.
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What is the maximum weight could 26 1 3/8 tire and tube could withstand? I bought my first bike few months ago, and it is old Raleigh 26" 1 -3/8 size. Every time I go with this bike through some bumps the rear tire and inner tube get punctured with large hole. It is written in the tire that the maximum weight is 70Kg and I am 80Kg. Is it the quality of the inner tube and tire makes it vulnerable to puncture? (we only have some cheap chinese tires and tubes in my country) Or the size will not fit with my weight? Or I can find a 26" tire and tube that could hold my weight? <Q> You are not putting 80 kg of weight on either tire; you're putting 80 kg + bike weight (say, 15 kg) on both tires combined, probably about 60% on the back, 40% on the front. <S> So, about 57 kg on the back. <S> In any case, I doubt very much that your weight is making you more susceptible to flats. <S> The quality of the inner tube doesn't affect puncture resistance very much. <S> The tire does determine puncture resistance. <S> Some tires are engineered for light weight, some for flat resistance, some to meet a price point. <S> This permits the tire to bottom out against the rim when you hit a bump, causing what's called a "snakebite flat." <S> So a first step towards preventing flats is ensuring adequate inflation. <S> Here's an inflation calculator . <S> The other main cause of flats, as you might imagine, is road debris. <S> There's not a lot we can do about that other than try to avoid it. <S> If I unavoidably ride through a patch of broken glass, I'll try to wipe down my tire with my (gloved) <S> hand immediately after, but realistically, the damage is probably already done. <S> If you think this is a likely culprit, you might try tire liners, which fit between the tire and inner tube and provide an extra layer of protection. <A> Minor point <S> but you state the bike is old. <S> There's nothing wrong with that, but its quite possible that the tyres and tubes are also old. <S> Sunlight, heat, and ozone do damage to rubber over time. <S> So a tube might inflate okay but not cope with the peak force of a bump. <S> If you can tear the tube using your arms, its old and needs replacing. <S> If the tyre has excessive cracking, looks dry or brittle, or you can see the canvas because of wear or flakes falling off, replace the tyres. <S> If your braking is bad, replace the brake blocks/pads. <S> They can look perfect but be hardened and no longer provide predictable friction to the rims. <S> All these parts are "wear" parts, aka consumables. <S> So if the bike fits you and is mechanically sound, is worth looking after it with basic refresh like this. <A> IMHO, its most likely a 'Snake bite', as covered by @Adam #3. <S> Where are the holes? <S> Does the tube have two holes or marks close together (hence the name "Snakebite" ). <S> The next most likely possibility is you have something sticking though the tire or rattling around loose inside the tire. <S> When you remove the tire and tube, pay attention to where the tire is in relation to the valve <S> (mark it if needed). <S> When you find the hole, look inside the tire at this place for something stuck in the tire. <S> When you put the tire on, align a label with the tube valve so the tire/tube is in the same place. <S> This is done so if you get another puncture, and its in the same place as an earlier one, you know you probably missed the thing causing the puncture. <S> Don't write off just plain old bad luck. <S> I once punctured 3 times in less than 6km... <S> Sometime it just decides that today is not your day....
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One important cause of flats is under-inflation, which can happen with any kind of tire or tube. Rubber parts perish with age, meaning they loose strength.
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Chain loosening over time (Fixie) I've ridden a fixed gear bike for years now, but I've only just questioned if I have been doing something wrong when adjusting the chain.You see, I have to tension the chain (pulling the rear wheel back) every now and then, roughly once a month because the chain becomes very loose with regular riding. At first I tried to keep the chain as tight as possible, so that there's pretty much no latency in the pedals when the bike is stationary (don't know if this is the correct expression) but then I read somewhere that doing this with fixed gear bikes can damage the drivetrain, and you should actually have a little latency and thus a slightly loose chain. In short, my questions are:Is it normal that I have to tighten the chain probably at least once a month because it gets too loose with casual riding, no more than a 100 miles per week? Is it correct that with fixie you shouldn't keep the chain too tight because it can ruin the drivetrain? <Q> Is it correct that with fixie you shouldn't keep the chain too tight because it can ruin the drivetrain? <S> That is mostly correct. <S> It is recommended to find the tightest spot and tune the chain tension to be just right in it. <S> Then, just in case, you can find the loosest spot and make sure the chain won't hop off the teeth if shaken in the second position. <S> Overtightening a chain would not give performance benefits while simultaneously it would start pressing both chain and chainring excessively, not benefiting their wear life. <S> Is it normal that I have to tighten the chain probably at least once a month because it gets too loose with casual riding, no more than a 100 miles per week? <S> If it is not the rear wheel axle sliding forward because of a low torque on its axles or because of bad nut design/quality, then it is the chain. <S> You would have noticed the axle sliding because the rear wheel would become misaligned in the rear dropouts and the tire would start rubbing one of the rear chainstays. <S> It is possible that a chain of poor quality would wear faster than desired, effectively "stretching" itself and thus becoming loose on the drivetrain's teeth over time. <S> I've read reports that so called half-link chains used in BMX are quite prone to it. <S> Try using a better, possibly more expensive chain. <S> Again, if the chain seems "loose" to your taste <S> but you cannot throw it off the drivetrain's teeth by hand <S> , it is unlikely it will come off during riding. <S> In that case, let it be for a while. <S> And again, do not forget about regular maintenance of the chain, <S> that is, replacing it after it has worn and become longer by 0.75% of its original length. <A> There are already some exhaustive answers in this thread, I won't be repeating those. <S> To shortly answer your questions: <S> no , I don't think so. <S> I've ridden a fixie myself and after about 500km I've loosened my chain because of the reason given in your second question. <S> Since then it's been more than 500km again, no chain tension adjustment needed. <S> yes , you're correct about damaging the drivetrain, stretching the chain and putting excessive (and uneven) stress on the bearings in the bottom bracket and the rear axle. <S> If applying a correct torque to the nuts of the rear axle doesn't help perhaps you should resort to one of the following items mentioned in this answer: https://bicycles.stackexchange.com/a/56603/34697 ? <S> Those are: serrated/star washer <S> chain tension adjuster, is only to be applied to the rear-facing dropouts. <A> The rear wheel should not simply be pulled back so that the chain is taught. <S> Doing so would accelerate wear. <S> When properly tensioned you should be able to move the chain about 12mm (0.5 inch) up or down about halfway between sprocket and chainring. <S> To rule out wheel movement, you could invest in a set of chain tensioners that fit in the dropouts. <S> These will also make setting chain tension and wheel alignment easier. <S> As usual, Park Took has a great video on single speed chain replacement and tensioning: . <A> Other answers have already covered the part about why chain should not be too tight, so I will answer only about chain wearing. <S> It is not normal, but not completely unheard of. <S> The worst singlespeed chain I have had wore out in about 1000 km and had to be tightened halfway during long rides. <S> It was marketed as rust proof, I guess the idea is that the chain would wear out before it had time to rust. <S> It was not because the wheel was moving in dropouts, and switching to a different brand solved the problem.
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Given that the circularity of the chainring, bearings and rear sprocket are never ideal, there will be a position through a full crank's rotation when the chain is the most tight, and a position where it is the most loose.
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My next bike: a tri bike or a road bike I currently have a mountain bike with thin road tires on it (because I ride only pavement). I’ve been starting to train for triathlons, here lies the problem. Should my next bike be a triathlon bike, or a road bike that I just put aero bars on? If I go with the tri bike I still have my mountain bike for strength training If I go with the road bike I may need to purchase a new seat post <Q> That would get my vote. <A> From what I have seen of used bike prices you generally will get more bang for the buck buying a standard road bike. <S> Considering you have a budget, I think you will get a newer bike with better components for the same money as an older well used TriBike. <S> There are generally quite a few mid tier road bikes with low usage on Craigslist, Ebay, etc. <S> When you get to the point that your training times are limited by your equipment it is time to upgrade. <A> Big personal opinion factor in this question, but I think subjectively it can be said that a road bike is the better choice when coming from a mountain bike. <S> The road bike will be more versatile, which means you can ride it more, and on more routes and therefore have more training options. <S> Many more choices on the used bike and component market <S> I don't think training on a tri bike with an aggressive aero position and a mountain bike with a more upright position is a good idea. <S> You want to be training in the position on the bike that you'll be racing in so that you muscles develop to accommodate and produce power that position. <S> On a road bike you can train using the regular bars because that puts you much closer to the aero position.
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A road bike is more versatile.
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Replacing a normal hub with a dynamo hub I'm the owner of a Kona Sutra 2017. I'm pretty happy with this bike, but I'm looking to get a dynamo hub for it, with some lights and maybe a charger for my phone. So far I managed to figure out that the front hub is a Deore HB-M525A. This would require me to find something that supports a disc brake with 6 holes and 32 spokes. My candidates are: DH-3D32 DISC HUB DYNAMO And that's about the only one I can find that would fit, sure there are one from SON, but the price is a factor x7. This a valid option for me, and what kind of lightning would fit this dynamo? It seems like it's a bit hard for me to find these parts. <Q> I hope you are aware of the fact that replacing the hub requires re-lacing/rebuilding the complete wheel. <S> I was about to suggest using a spoke dynamo, e.g. Sunup Eco MaxiDyn 6V12W <S> but after seeing a price tag (far above €200) I came to the conclusion that rebuilding the wheel with a hub of €50 is still cheaper. <S> Furthermore, Sunup is to be mounted on the rear wheel, where the OP has already a cassette and brake disc on both sides, hence no space for the dynamo. <S> Some years ago AUFA was delivering front wheel mounted spoke dynamos, unfortunately they are nowhere to be found now. <S> Coming back to the original question: bicycle voltage generators, afaik, are standardised on 6V and the one you've chosen is capable of 3W of power. <S> This means that any standard bicycle lighting is suitable as long at the total consumed power <S> does not exceed 3W <S> (e.g. front light of max 2.5W and rear light of max 0.5W). <A> I've just ordered a new wheel rather than get my old one rebuilt with a dynamo. <S> All I'd have kept of the old wheel would have been the rim and disc brake rotor (and tyre, but they're consumable). <S> Mine's being built on the SP PD8 (website warning: autoplaying bagpipes!) <S> which is certainly available in 6-hole disc brake and 32 spokes (though mine will be 36). <S> I'm going for the Axa Luxx 70 Plus front light (with USB charger output). <S> The rear light is one I got second hand. <S> The whole upgrade is on a budget for me, and this looked like the cheapest sensible approach. <A>
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If it's just for a light (not the USB charger), Reelight can be an alternative for a hub dynamo
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Can rusting of chain be slowed? I have been using a silicone spray on my chain, but it isn't long before it rusts. Anything better? What about about Squirt Long Lasting Dry Chain Lube ? Thanks. <Q> We don’t give specific product recommendations but the following general advice should help reduce rusty chains: <S> don’t store your bike outside. <S> If you do, put it under a breathable cover. <S> Morning dew is a considerable source of moisture so check your bike in the early morning to see if it’s wet. <S> wipe down your chain after it gets wet. <S> Having a dedicated shop rag for your chain helps <S> if your oil-based chain lube washes off too easily, try a wax-based lube or vice versa. <S> Note that nothing is corrosion proof and you’ll still have to do all of the above <S> Or, accept that some degree of rust is part and parcel of having a working bike (as opposed to a display bike), note that rust only accumulates on the non-moving and non-wearing side plates of the chain, keep it lubed where it matters (internally on the bearing surfaces) and be happy. <A> Dry storage of the bike, ride only in sunshine, you get the idea... <S> Keep water from the metal . <S> Use an oil that thoroughly sticks to your chain, and the water will have a hard time to reach the iron. <S> Wax or fat may be even more effective in keeping water away from the chain, but they attract dirt to the chain like hell. <S> Move the chain . <S> Rubbing metal on metal constantly removes any rust before it becomes a problem. <S> However, the movement needs to be frequent enough. <S> A week in the rain without moving, and your chain is one piece. <S> Use stainless steel . <S> You can buy chains made from stainless steel, and in my opinion, they are well worth the extra dollars. <S> To me, the most painless solution is the last. <S> Of course, it's still a good idea to keep it well oiled... <A> One of my bikes lives outdoors 24/7 in all weathers (in a rainy country). <S> It's cheap and not very attractive, so I'm concerned with rust that affects the workings more than rust that affects the looks. <S> On this bike, I use GT85 (light spray oil with PTFE) for the chain and derailleurs. <S> I take the chance to oil it when it's dry, which isn't all that often in the winter. <S> The chain maintains a dull grey colour (typical of exposed steel), rather than a rust colour, so long as I don't leave it too long. <S> A light spray of oil over the sprockets keeps them from rusting too much as well. <S> It's only ridden on tarmac, and is never cleaned, because it shuttles between the station and work and never goes home). <S> I tried a corrosion-resistant chain on this bike (or its predecessor) and found it to rust quite quickly when I forgot to oil it. <S> If you're interested in looks, stainless is the way to go, but stainless is less tough than normal chain steels. <A> I think rust is a symptom of insufficient chain lube and not a problem in and of itself. <S> Regularly apply lube, make sure to wipe the chain clean before and after lubing. <S> Use dry lube for dusty conditions and wet lube for wet/rainy conditions. <S> How often you have <S> to re-apply lube depends on conditions as well. <S> A single ride in bad weather can be enough to make re-lubing necessary.
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A bit of superficial rust won’t harm a chain but insufficient amounts of lube will significantly increase friction and wear. Ask the staff at your local bike shop what they recommend for your local climate and terrain if all fails, try a chain that has corrosion resistance as a feature. There are four ways to reduce rust: Keep water away .
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Why do so many people put the inside pedal down when cornering? When learning to ride, my dad taught me to always have the inside pedal up when cornering. He reinforced the lesson by telling me about a race he'd been in where someone clipped a pedal when cornering and took down 20-30 people in the pack behind him as he went down. To me it's quite intuitive to keep that inside pedal up - it keeps it away from the ground when leaning into a corner and I'll often even hang my knee on the inside as I'm leaning to lower the center of gravity even further. Additionally, I think that I'm actually pushing on the outside pedal as I go around, which also feels very natural to do. The vast majority of people I see riding these days (recreationally or light competitive, not professionally), including (much to my chagrin) my own children, insist on putting the inside pedal down when turning. I suppose that there is a belief that "my foot is closer to the ground, so if I start to crash I can save myself more quickly", but it just seems so totally counter intuitive and unnatural to me. It feels very unbalanced to have that inside leg down, like I'm going to fall over on it. Why does this feel like the "right" way of going around a corner to so many people? <Q> People put the inside pedal down because it's the natural thing to do. <S> You want the bike to lean to the left, so you press down on the left side; you want the bike to lean right, so you press on the right. <S> Putting the outside pedal down is a learnt behaviour, so it's only done by people who have been taught it. <S> Pedal strikes simply aren't an issue for most cyclists. <A> I guess it's because when you lean to the right you'd naturally expect your weight to be on your right-side leg -- IOW <S> your right leg is straight and load-bearing, and your left is bent/relaxed i.e. off the ground. <S> Once your pedal ever scrapes the ground <S> I think you change your mind about the correct way to do it. <A> Been at races where the competitors have ground down the pedals to allow continued pedalling through the turn. <S> I often keep my cadence through a turn on road and typically will stutter on a trail turn because I lack confidence in the traction holding. <S> There are times when negotiating a tighter turn or when an obstacle or oncoming traffic forces a path change mid-turn that my stroke ceases, my turn side leg is up and that side's knee is leaned away from bike (into the turn) which gives me a tighter response... <S> the turn becomes sharper. <S> The benefit of my outward movement of the knee is questioned by some, and I've linked an article by Sheldon Brown that outlines his, and other bicyclists, views. <S> It's most critical in turns to keep on top of the saddle and lean with the bike. <S> Perhaps that's better said, keep your body in line with the center of gravity of the bike. <S> Here's a quote from the artcicle I've linked below:"Leaning the upper body and the bicycle together, keeping them in line as when riding straight. <S> This technique has the advantage of keeping the steering axis, tire contact patches and center of gravity all in the same plane. <S> This preserves the proper handling characteristics of the bicycle, and makes a skid less likely. <S> "Best <S> to have turnside pedal up. <S> Seems that's what you'll witness an experienced cyclist go to in a hot corner.
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Also, most people don't cycle fast and aren't on road bikes, so they're not leaning the bike much and they have reasonably high bottom brackets.
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How can I prevent my next bike from being stolen? I park my bike in my building's bicycle room, in the parking garage in the basement. The garage door can only be opened with a remote fob, and the bicycle room is locked as well. In the garage, I secure my bike using a U-lock, and a chain lock. This morning, I came to find a hole in the door, and the two locks cut by what looks like an electrical saw. What can I do to avoid that should I buy a new bike? <Q> That sucks. <S> I'm sorry that your bike was stolen. <S> there's not much you can do about it. <S> If there are lots of bikes in the bike parking area you can make your bike a lower priority target by increasing the number and strength of the locks, and by making the bike itself look less desirable. <S> Looking at the first picture, it seems the bike parking area door could be easily opened from the inside. <S> The thieves were able to cut a hole in the door and reach the door release - not the most secure setup. <A> There's nothing you can do if the storage area is not under constant surveillance. <S> It can take as little as 2 minutes to grind a U-Lock. <S> The only real solution is to keep your bike in your apartment. <S> In the meantime, check to know how the thief was able to get in that area ? <S> did he came via the garage door ? <S> the front door ? <S> Did he enter while someone enter or leave without checking ? <S> Check with your home insurances to see what can be done about that, if the building is responsible in some way. <S> Anecdotal: When I come in my building, if someone is waiting to be let in, I tell them to wait outside and wait and not come at the same time as I do <S> and if I leave by the garage, I wait until the door is closed before either leaving or going down the ramp. <A> I lost a few bikes to theft when I was in university. <S> It stunk. <S> I took to buying used bikes (probably from bike thieves). <S> I wrapped the frame tubes of my (otherwise nice) bike in peelable masking tape, then smeared them with grease. <S> Nobody wanted that ugly bike. <S> It worked to prevent theft; I kept that one for many years. <A> Funny enough, the parking garage may actually be less safe than a well-exposed outside location. <S> When I was commuting between the cities of Hamburg and Berlin I locked my (500/1000$) bikes at the train stations, sometimes for weeks. <S> I made sure to detach and lock my front wheel together with the back wheel and frame though, on some steel pole or railing, with a good-quality U lock. <S> Just one time in two years <S> or so somebody stole my suspended saddle post. <S> Both stations have their share of homeless and drug-addicted people hanging around; but the places are busy 24/7. <S> I suppose your average friction saw creates too many sparks at night to go unnoticed in public; but in a parking garage the thieves have all the time in the world. <S> So try the next intersection next time. <S> And yes, use a bike which is not a special target. <A> There are motion sensors (installed on your bike) and locks that can notify you if your bike is being moved. <S> I don't have direct experience with them, and they're obviously expensive, so you'll need to decide whether something like that is worth it. <A> Check the quality of your locks ! <S> I suspect both to be breakable with a bolt cutter (yes, your u-lock too). <S> You will learn more here : <S> For owners, a second option is more onerous, but will not benefit only to you. <S> Install a camera. <S> Put it high enough to reduce the risk of being destroyed. <S> This may even protect the whole garage, not only bikes.
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If thieves are willing to break into a locked garage, break into a locked and fully enclosed mesh bike parking area then cut two bike locks using power tools: Just store your bike in your apartment if you can. Also, it's likely that someone let them into the garage - i.e. one of your neighbors. Be sure to have access to data even if it is destroyed.
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Crack on underside of handlebar I found a crack underneath the handlebar. Is it okay to keep using it? I can't really afford a new one. I'm riding with the cracked bar right now and there's no weird sound and movement on the handlebar. To make things easier to explain, here is the crack Not sure what happened. I can feel the crack with my hands and I felt a string like material on the crack. I lent my bike to my brother and he came back with a broken bike. I replaced the broke parts and I didn't check the handlebar until when my friend noticed a strange white line under the bar. I already know it needs replacement immediately. Please tell me what cause the crack so I might avoid the same problem again in the future. <Q> DON’T <S> From your description I’m not sure what’s actually cracked (stem, fork’s steerer tube, frame’s head tube?) <S> but replacing it is much cheaper and less painful than new teeth or sitting in a wheelchair the rest of your life. <S> Post a picture if you want a more accurate assessment but generally the only components on a bicycle where I’d be okay with imminent failure is anything related to gear shifting or attachments such as bottle cages or mud guards. <A> If the crack is in the handle bar, the failure mode is as follows: <S> One side of the handle bar breaks off. <S> You fall forward, one hand pushing the broken off handle, the other hand pushing the still connected handle. <S> This falling motion <S> will steer your bike sharply to the side with the broken off handle, effectively kicking your bike out from underneath your butt. <S> You will make contact with the road at the full speed you were riding at . <S> The resulting damage depends on your exact speed and road conditions, but I've had this type of accident once at about 20 km/h on a smooth surface (no sharp edges or bumps from tree roots, uneven sidewalk tiles, and the like), and it's still the third most severe accident <S> I've ever had. <S> Note that the energy that goes into bruising you will go up with the square of your speed. <S> So, at 30 km/h you have to expect more than twice the injuries than at 20 km/h. <S> Do this at 40 km/h, and you'll have to hope that you are found before you bleed to death. <S> A crack in the stem itself may give a similar failure mode, or it may break directly forward. <S> I don't know what would happen in this case, but my intuition tells me that this would be much more dangerous than falling sideways at full speed. <S> Bottom line: <S> Your fork, your stem, your handlebar, and your steering tube are too critical for your security to ignore cracks. <S> If any of these fail, there is no backup , and the failure modes are scary. <S> You won't have any chance of mitigating the consequences of the crash. <A> Yep. <S> That CF handlebar is trash. <S> A dent or indentation, or loose carbon fibers that are free of the epoxy matrix indicate carbon fiber composite it is seriously damaged and weakened. <S> You know how this got damaged. <S> Your brother crashed your bike. <S> Simple as that.
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If you are sure (or have strong suspicions) it’s a crack and not just a scratch, stop riding it. End of the bar hit the ground, bar broke. BTW, it doesn't matter that you can't afford to replace broken components because your brother owes you and should pay for the damage.
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Safety guidelines when using MTB clipless pedals on a road bike Yesterday, I went for a ride and my legs felt really great (hadn't been cycling for about 2 weeks) so when I was climbing on a hill, I decided to go on a full blown sprint and unfortunately... somehow my leg got released from the pedal and on the push down, my foot hit the ground and that was enough to get myself flying over the bars. I got used to the regular road bike clipless pedals and that never would've happened with them, what should I do in order to not fly over the bars again on my next sprint? I use the clipless MTB pedals on my road because the extra I had really helped me with my knee. Solution:It's quite apparent that the springs were just too loose. I can now lift the bike with the shoe on it easily. <Q> This answer is for SPD pedals, which are the most common MTB pedals. <S> Other systems do not have multi release cleat, and some don't even have adjustable springs. <S> First: make sure you do not have multi-release cleats. <S> They are designed to release when pulled up hard enough, and can be distinguished by letter "M" stamped to them. <S> If the cleats are too worn to tell whether they have the marking, it's probably best to replace them anyway. <S> Second <S> : Adjust the release spring tension so that the pedals are easy to unclip <S> but not any looser. <S> Too loose pedals may release unintentionally. <S> Third: If these do not help, it's probably time for new pedals. <A> I use MTB shoes and pedals (Crank Bros Candy) on the road all the time and have never had a problem. <S> Mountain riding probably involves more short, high power bursts than road riding does. <S> I believe road pedals have a wider base and different retention system because there is less need to accommodate frequent clipping in and out, not to support higher pedaling force. <S> You should examine your pedals and cleats and look for excessive wear and play between the pedal and shoe, or low disengagement effort. <A> I used to swear by Speedplay Zero Road pedals before I got into racing gravel and MTB. <S> After that, it just made total sense to have shoes and pedals that can be used on all surfaces and all of my bikes. <S> I still have some friends that use those 3 bolt SPDs and are always fidgeting with them, picking rocks out, or kvetching about squeaking and duck-walking <S> You don't necessarily have to switch shoes either. <S> There are adapters to convert a 3 bolt shoe to a 2 bolt cleat. <S> Singlespeed MTB doesn't allow for a light touch on pedals on the hills, and there's no dancing up them like Contador. <S> It's a gut-wrenching, muscle searing slog up steep pitches that are constantly fighting back with every bit of rock, grit, and inch of incline. <S> I'd also point out that MTB pedals most likely experience more pulling on the upstroke than any road pedal, as inclines off-pavement are often steeper and more technical, thus requiring more effort on the upstroke (granted, I haven't found any specific study to validate this) <S> I think it'd be difficult, <S> nigh impossible, to find objective studies on pedal stroke efficiency that weren't from biased sources like pedal mfrs. <S> I don't recall where I read it <S> but, other than in pure sprints and steep inclines; it's largely a myth that riders pull on the upstroke. <S> It's more that riders will unload the rising crank arm, but maintain connection and begin engagement on that side as the pedal crests over the top. <S> My personal favorite on the road bike has become Ritchey's WCS cleats and their Road-WCS pedal. <S> The Ritchey cleat works with all Shimano MTB pedals as well. <S> (But not vise-versa.) <S> https://us.ritcheylogic.com/us_en/bike/pedals/wcs-micro-pedals-v2
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I don't see why MTB style pedals would present a greater risk of the cleat coming out of the pedal under high power than a road style pedal would. A new set of cleats and adjusting the depth of the cleat in the shoe sole will probably help.
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Are there reasons not to use always the max level of assistance? I'm using an electric bicycle to go to work. My goals are: Not to arrive late Not to sweat (too much) My bike, like most e-bikes I guess, let me choose the level of electric assistance that I wish. I understand that the range is longer with a lower level of electric assistance. But in my case, this is not relevant. My battery can take the whole commute regardless of the level of assistance. Is there any reason I should not use always the maximum level of assistance? For instance battery or motor damages/heating/...? <Q> Assuming you have a good quality electric assist bike from a major manufacture. <S> It's a safe bet the bike is built to take the max assist torque without sustaining damage or accelerated wear. <S> If the manufacturer believes sustained use of max assist will affect the bike, it will say so in the manual, so check that. <S> The one thing I'd be mindful of is battery life. <S> General advice for laptops, phones and other portable devices is that deep discharge and heat degrade batteries and shorten their life-spans. <S> If your commute is short, and the battery capacity is adequate for max assist both ways, that should not be a problem. <S> I'm not sure about how discharge rates affect battery life - if I find info on this I'll update this answer. <S> Otherwise I say go ahead and use max assist. <S> Yes, more torque and speed will wear bearings, chain, etc. <S> proportionally faster, but using the assist is what you bought the bike for, right? <A> I don’t always use full assist for the following reasons: Range and Battery life. <S> I can almost double range by biking more. <S> This is especially the case when I’m down to 1-bar on the battery level <S> so I pedal on the flat portions and keep the assist for the climbs. <S> Exercise: sometimes you wanna ride a bike, get those juices flowing <S> Go faster: my ebike has e-assist capped at around 25km/h. <S> So while I’m not deliberately dropping the e-assist level, the bike does so for me as I approach 25kmh. <S> If I want to go faster, I have to pedal. <S> Stealth: <S> especially on bike trails, I’m conscious of being on an ebike even though I only go at bike speeds. <S> The whirring of my geared hub motor is quite noticeable. <A> Too much assistance makes riding at slower speed uncomfortable. <S> For instance, if I select 15 km/h speed on a flat good road because of any reason (people walking there, nice views around, staying with the group that picked such a velocity, etc), full assist accelerates me too much. <S> To slow down, I need to stop pedaling, then the velocity drops. <S> Then I pedal again, the velocity increases and goes over the desired limit again. <S> These rush/slow iterations are annoying, it is much more comfortable to select the level of assist that matches the needed speed. <S> I think it is not a simply "bad controller" issue. <S> There is certain amount of power the human can comfortably contribute without thinking about and much less may be less comfortable. <S> Turning pedals with no resistance yet precisely at required speed needs more attention. <S> In some degree this can also be fixed by shifting to the higher (not lower) gear - takes less power from the engine at the same speed. <S> But gear alone seems not good enough for all cases. <A> Using more assistance puts more strain on the battery and motor. <S> This will cause those parts to wear out quicker. <S> Also, the bicycle's drive train itself may suffer unnecessary wear. <S> When starting from a stop, it's much easier on the bike (chain, sprockets, chainrings, spokes , etc) to put the bike in an easy gear and use the mechanical advantage of the gears to start yourself off without putting too much power through the drive train. <S> However with an electric bike, it's all too easy to leave the bike in a harder gear and let the motor do a lot of work. <A> Higher discharge rate (at higher assitance levels) causes accelerated battery wear (source: <S> figure 4 of this article ). <S> That said, if you're discharging below 1C (for example at 250W legal limit on a standard 360Wh battery), the difference is very small and you shouldn't be concerned.
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This puts extra strain on the parts of the bike, causing them to wear out prematurely. From a maintenance and longevity point of view it's probably not the best idea. The manufacturer provided the max assist setting, so they intend for it to be used. Do not let the stupid engine with no eyes to decide which velocity is the best for particular road.
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Looking for ideas on how to track bike wheel rotations or distance traveled I want to build a hack where when my stationary bike hits 0.1 miles, it sends an information to a webserver which would trigger a web API call. I understand how the webserver and API call would work. I wanted some ideas on how the said hardware(mcirocontroller or other) would function on the bike itself. <Q> Magnetic sensor into a micro controller would be trivial and is not really a bicycle question. <S> ANT+ sensors follow a standardized API so you could look for a micro that support ANT+ and look at the ANT+ API for bicycle sensors. <S> Not sure how the accelerometers go on stationary bikes as they auto calibrate distance/revolutions, and a stationary bike has 0 distance. <S> I will ignore GPS... <A> A bicycle wheel has a nominal radius, plus a tyre on the outside will give you a diameter. <S> That will give you a circumference, something like 1500 <S> -2500 mm depending on the wheel rim size. <S> So set up a reflective patch between two adjacent spokes, and use an optical sensor to detect when that patch goes past. <S> Simply have tuo tune the sensor <S> so it doesn't see spokes, but does see the reflector. <S> If that doesn't work, you could use a magnet and a magnetic pickup like a simple bike computer. <S> Each pass is one wheel revolution. <S> Simply count the pulses and send your interrupt/trap/signal/message when you hit 72 pulses/wheel revolutions (assuming a tyre circumference of 2235mm) <S> There are 160,935 millimetres in 0.1 miles. <A> A hack I've used for 1 or 2 bits of I <S> / <S> O in the past is to use the status lines of a cheap USB-RS232 adaptor. <S> These are easily addressed in any programming language, so could connect directly to your server if it's nearby, or a single board computer like a raspberry pi. <S> Then you just use a magnetic bike computer switch from 5V (taken from the USB line) to DSR, and a resistor to USB ground. <S> USB-232 <S> converters tend to run with 0V where the 232 spec says they should have a negative voltage. <A> If you're more into programming and embedded software (or want get into) you can simply google for e.g. "raspberry pi bicycle trainer" or another DIY embedded platform. <S> Enough ideas will pop up. <S> The advantage of the raspberry pi (besides its price) is that it already has network connectivity and can run web servers on its own. <S> Nevertheless, it's not a bicycles.stackexchange question but rather stackoverflow or some embedded forum.
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Two main technologies picking bicycle speed are magnetic sensors and pickups counting wheel revolutions and ANT+/Bluetooth sensors with accelerometers counting wheel revolutions. Cheap bike computers tend to use reed switches; more expensive ones may use Hall sensors that would take more interfacing.
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Wider tires offering faster speeds and safer ride? I'm looking at riding again. I took a two year break after I crashed going down a hill when a tree branch was down and I went over my handlebars. I've always assumed that thinner tires were better for riding but I was watching this video from Global Cyclist Network. In the video the rider makes a strong argument for wider tires. What I'm wondering is there any literature or empirical studies that are public that show these results? I found some small things that corroborated this but I was sure this would be the right place to ask. <Q> Depends what you mean by 'better', and under what circumstances. <S> The major tire considerations are, in no particular order: Drag or resistance <S> Comfort <S> Grip Durability / puncture resistance Mass <S> Aerodynamics <S> What constitutes a 'better' tire for you depends on your preferences and what kind of riding you want to do. <S> The hypothesis that GCN puts forward in a few of their videos is that narrower tire width and higher pressures do have lower rolling resistance on a smooth surface, but wider, lower pressure tires actually offer less overall drag over irregular or bumpy surfaces because they have less suspension losses . <S> GCN did some relatively well controlled experiments on cobbled surfaces. <S> Here is a video that talks about what they did and the results they got: Some more experiments on bumpy surfaces: https://janheine.wordpress.com/2016/06/14/suspension-losses-confirmed/ <A> In addition to the "bumpy road" effects that Argenti mentions, consider this: two identical tires, both at the same pressure and both equally loaded, except that one is fat and the other skinny. <S> They'll both have the same size contact patch, but the fat tire will have a relatively circular contact patch, and the skinny tire will have a more ovalized patch; the skinny tire will also have more vertical deflection at the center of that patch. <S> When the tire deflects, you get hysteresis losses, so less deflection is be better. <S> This gives the advantage to the fat tire. <S> It turns out that you can't really make a fat tire with as lightweight a casing as a skinny tire, so if you have a fat tire with a light casing, you need to run it at lower pressures (or make it heavier, and get more hysteresis as a result). <S> It turns out that the tradeoff is worth it--you still get lower hysteresis losses (also, happily, fat tires are naturally less susceptible to snakebite flats, so you can get away with those lower pressures). <S> This has been written about here and here . <A> It's actually a sliding scale between energy lost to massage the tire, and energy lost due to road conditions: If you ride on smooth roads, a relatively thin tire will give you the least resistance because it requires the least massaging of rubber. <S> I think, the optimum is at the wide end of racing tires, or at the slim end of all-round tires. <S> If you ride on bumpy cycle paths, the thin tires will bounce too much on the roots and potholes. <S> A wider tire will reduce this bouncing, and thus give you the least resistance. <S> This is squarely within the range of touring tires, as far as I can tell. <S> If you want to go off-road onto soft, sandy paths, you need to reduce your tire pressure even more / use even wider tires. <S> Again, these wide tires will give you the least resistance because other tires will move too much sand, and thus loose energy. <S> Here we are talking about wide mountain bike style tires. <S> In each case, there is a best tire width, and that best width varies wildly. <S> So, take a good look at the types of roads that you want to ride on, and choose a tire width accordingly. <S> Then pay attention to your riding: <S> If you find that the bumpy parts of your rides are slowing you down too much, you may go for a slightly wider tire the next time you swap tires. <S> If you find that even the strongest bumps you encounter are not slowing you down the least, you are likely wasting some energy due to the larger rolling resistance of your wide tire. <S> Try a slightly thinner tire the next time you swap tires. <S> With this, you'll eventually find a tire width that's perfect for your rides.
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The idea is that because wider tires don't necessarily have more drag you can run wider tires and get better grip and comfort without a penalty.
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Is it ok for a kid's bike to only have a front brake? My wife picked a bike (with trainer wheels) for my 3yo son. It only has a front brake. Having gone over the handlebars once when I was just using the front brake, I'm a bit worried about this. Should I be? (Now that the bike has arrived, it has a rear coaster brake.) <Q> Small children usually do not have a grip strong enough to brake effectively with brake levers on the handle bars. <S> Neither do they have enough coordination to modulate brakes. <S> This means if they were able to brake the front wheel effectively they would indeed be at risk to go over the bars. <S> Typically, children's bikes have coaster brakes . <S> These allow to stop by back pedaling. <S> Which is an elegant solution: If the child is capable of accelerating by pedaling, it is also capable of braking by performing the inverse motion. <A> Everyone has to fall off their bike sooner or later. <S> So while I pad them up and have helmets, I don't go overboard on worrying about their safety. <S> Should you worry? <S> Not unduly, if the child is riding on grass and reasonably dressed then they should be fine. <A> For one, your kid's bike likely has a coaster brake. <S> Check that. <S> If it doesn't, either add a second brake or buy a bike with a coaster brake. <S> Apart from the danger of going over the bars, there is also this: Every vehicle must have two independent brake systems <S> , otherwise it's simply not fit for the road. <S> This is independent of the type of vehicle, and bikes are no exception. <S> This is both a legal thing (at least in my country, and very likely in any other sane jurisdiction), and a safety issue: Brakes can, and do fail . <S> You don't want your child sitting on its bike going downhill when the cable actuating the brake fails, and not have a backup available. <S> I have completely lost track of how many braking cables I've managed to tear, and I've been very thankful for my coaster brake each time. <S> So, as I said, either your child's bike has a coaster brake, or you need to do something about it. <S> Daniel R Hicks tells me that some US states allow coaster-brake-only bikes. <S> So, I guess, I have to exclude the US legal system from the list of sane jurisdictions. <S> Maybe they see it as a personal freedom to be allowed to endanger yourself? <S> Especially when they are older and lengthened from wear. <S> If that happens going downhill on a coaster-brake-only bike, you are screwed. <S> If you care about safety, one-brake bikes are just a no-no.
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Anyway, while your state may allow you to use a coaster-brake-only bike, the safety issue remains: Chains can and do jump off the sprocket, or even break. I get my kids to ride around on grass secure in the knowledge they will crash or fall and learn an important lesson before they're old and big enough to hit the road. You must have a backup to avoid the worst .
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New high quality tire doesn't sit evenly on the rim It's my first tire change experience and I got so far using youtube videos but now I'm stuck.Got these Schwalbe 365 tires yesterday for my folding bike.It is an all season model which feels a bit harder than the tire that was on the bike from the factory but both are 40-406 20x1.5".The bead doesn't sit properly on the rim. This is the case from both sides as seen in the images. There's a small misalignment between where the problem manifests itself on each side of the rim.The tube is also brand new (Continental). The temprature in the bicycle room where I tried is around 16-22 deg. Hadn't used soapy water when installing the tire and can't measure tire pressure (it's recommended 3-6 bar). What do you recommend to solve the issue? Update: bought a pump with gauge, rotated the tire and used a bit of liquid soap to end up with this result: One thing that I discovered today is that the tire is literally tighter at the point where there's a problem which makes me think the tire might have some issues due to how it was stored I the shop. But that would be too sad because despite the issues I really like these tires. <Q> The tire sidewall is just hung up on the rim a little. <S> It’s a common problem. <S> Deflate the tire until you can deform it a little with your hands, rotate the wheel so the problematic section is at the top. <S> Grab the tire from the side and lever it back and forth. <S> You should be able to pop it out so the bead sits on the rim properly. <S> BTW, a pressure gauge is a good investment <S> so you know you are inflating your tire to the proper pressure. <S> Here's a link to Park Tool's video on tire installation, at the point it addresses the bead being too high or low. . <A> Sometimes I've found that pumping up the tyre to the rated pressure (or a little over), deflating most of the way, and pumping up again does the trick. <S> You can chuck some water on the bead while its deflated (I use plain rather than soapy water for that; it's not as effective but doesn't leave a slippery residue) <S> You can also try riding a few hundred metres gently with the tyre fairly soft then pumping up hard. <A> Not sure if this helps, but I've had this exact same problem seating some schwalbe g-ones. <S> They were tubeless tyres <S> and I'd put tubes in them. <S> It didn't matter what i did, and I basically followed all of the above suggestions, they'd never seat properly. <S> The moment I removed the tubes and ran them tubeless they seated perfectly, clicked into the rims @ about 80 psi <S> and I've never had any subsequent issues with them. <S> The issue appeared at a random point just as yours have. <S> I have a sneaking suspicion that it was that the tubes put pressure on the wrong part of the tyre as its inflated. <S> So my suggestion is that you try with a different diameter tube. <S> I'm not sure if it should be larger or smaller, but give it a go with one you have handy. <S> Hope this helps. <A> When I fitted a new Schwalbe Marathon Plus, it kept bulging near the valve when I tried to inflate it. <S> The solution was to replace the inner tube with a smaller one. <S> I also discovered that the trick to getting the tyre on is to secure it with cords or cable ties as you work around, to stop one side slipping off. <S> Edit: <S> Thanks to the guys who suggested this in their responses. <A> Dont rule out the RIM Tape. <S> I was led to this post because I was having problems mounting some 30mm and 32mm tyres on a front rim. <S> I ruined the first tyre being a little too aggressive. <S> When I had the same problem with the second tyre I started to wonder if there was a problem with the rim itself. <S> Did the soap, did the higher than recommended pressure...still no luck. <S> Replaced the fabric rim take with some of that yellow plastic tape rim tape and on my next attempt the tyre seated perfectly. <S> The rim in question was shallow <S> and I think there was just enough friction with teh fabric tape to prevent the bead moving to the edge. <S> Shame about the first ruined tyre <S> but I am happy that I got this seated on the second tyre. <A> Pump up the tire more until it seats itself properly on the rim. <S> Deflate to desired pressure afterwards. <A> Make sure the tire is properly seated and the tube is not pinched anywhere. <S> Then pump up to maximum allowed pressure (or even slightly higher). <S> If the tube is pinched anywhere it will rupture with a very loud bang. <S> If you are unsure, better wear some hearing protection or do it outside and keep as much distance to your head as possible. <S> Deflate to desired pressure afterwards. <S> Sometimes <S> it’s actually the reflective stripe which is misaligned.
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Looking closer at the wheel after taking the tyre off I wondered if the fabric rim tape that was used could have been my problem. A pump with a pressure gauge is really useful for stubborn tyres, I run mainly Schwalbe, and some of theirs can be tricky, though I've had worse.
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Ride a bike only using the pedals Is it possible to ride a bike standing? I mean properly standing, not sitting up straight. Your feet are on the pedals but you do not touch any other part of the bike. If not, is it possible to roll/steer while standing? For maximal clarity I added this handcraftet picture. You may only have contact with the blue parts, and especially not with the red parts: <Q> I have seen that done with monocycles, but I am afraid that doing it with a bicycle is going to be more difficult if not impossible. <S> The reason I think so is that when you stand up and pedal you are also unbalancing your bike right and left. <S> If you do it while holding the bar, you can compensate it in a certain way. <S> (think cyclist standing while going uphill or sprinting, see how most of the cyclists in this picture are standing and their bike is tilted) <S> If you are not holding the bar, your bike will start zig-zagging and the only way to control it would be using your hips. <S> But that can happen if you sit and can transfer your hips movement to the frame via the saddle. <A> It’s possible to stand and roll, I’ve done it, but with knees touching saddle for stability, which is currently against the rules. <S> See YouTube for similar. <S> I wouldn’t rule out someone more athletic than me being able to comply with the rules after practise, for rolling at least. <S> As Daniel points out, the bike must be cooperative, so stable and balanced. <S> Some bikes will be more difficult than others. <S> Also see this for ideas of what would seem impossible being done..! <A> Artistic cycling <S> (YouTube link) seems to be a big thing in Slovakia, and merely riding standing with no hands would be a bit basic for these people, but they do pass through that position a few times (and <S> fixies mean they must be pedalling if their feet are on the pedals. <S> Certainly if you allow enough leeway for things like thighs in contact with handlebars, or holding hand with another rider, you can see them do that (while wheelie-ing) at 3:45. <S> Though the wheelie may mean you count it as more of a unicycle trick. <S> Again, while wheelie-ing here's another (1:34) -- and the rider has someone standing on his shoulders. <A> If the only contact allowed is your feet on the pedals, I do not think it is possible to balance for any sustained amount of time. <S> It only becomes possible when you allow a third point of contact to leverage against, such as a thigh against the top tube. <S> Only touching the pedals, if you try to push down on one pedal, the whole bike will go in that direction, and quickly fall over. <S> There needs to be another point of contact in order to have forward motion. <S> If you are holding still/doing a track stand, you control your side-to-side motion by holding the wheel at a ~45 degree angle and manipulating your forward-backwards motion as necessary. <S> If you can't redistribute your weight on the pedals to go forwards/backwards slightly without falling over, you will not be able to do a track stand. <S> If the bike is already moving and you have really good balance, you might be able to stand up for a second only on the pedals, but any need for corrective balancing will require at least one more point of contact.
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This is because the pedals are offset somewhat from the center of the bike, so you will not be able to use them without falling over if those are the only points you are in contact with. It's possible, for those who can do the seemingly impossible, at least if you allow the rider to do a wheelie at the smae time.
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Chain shortening only one link? Is it possible to shorten or extend a chain only one link as shown in the photo (in red square). Or do I have to shorten at least two links in order for the other end to match? The reason I'm asking is that with my current setup ( front 52/36, rear 32/11 ) if I remove one link the chain becomes too short to shift to 52 front and 32 rear . If I extend the chain one link and shift to 36 front and 11 rear , the chain rubs on the derailleur. <Q> For 1/8" chains as used on singlespeed bikes (or with hub gears), half links are reasonably common. <S> They do exist for 3/32" chains (which are sometimes used without derailleurs) but are much less common as single speed 3/32" chains are. <S> They're not needed if you've got a test derailleur as the derailleur provides much more chain length adjustment. <S> A chain tensioner can do this on a singlespeed. <S> The main reason for using these appears to be on singlespeed conversions, when they lack the horizontal dropouts of a frame built for single speed. <A> Unless using a special half link (as mentioned and linked to by Chris H) to shorten a chain you have to remove the same number of outer and inner plate links. <S> The distance between the joining pins is 0.5 inch so joined chain are always a multiple of whole inches long. <S> This raises the question of why you want to reduce the chain length by less then one inch. <S> Chain sizing and tensioning for both derailleur equipped and single speed or hub geared bicycles can be accomplished without the need to shorten a chain by 0.5 inch increments. <S> Update based on new info. <S> This is in agreement with what @Mike said but with specs and numbers. <S> Derailleur total capacity needed is (52-36)+(32-11) = <S> 37 <S> Tiagra long cage GS derailleur has total capacity of 41. <S> The short cage SS 33. <S> SS model can't take up the slack and is bottoming out the A pivot (what the cage rotates around). <S> Going to a GS model will fix the problem. <A> Simple answer is "yes". <S> And as it was said already, you need a half-link to be able to connect the chain again. <S> The question is - why do you need it for? <S> you can replace the rear cogwheel to the one with one cog more or less (depending on your preferences) to stick to the even number of half-links in your chain <S> if the problem is in your dropouts (road-type not allowing for adjustment) you can experiment with the "road-to-pista" dropouts adapters (I know those exist, I don't know how they perform) <S> The OP has shared some information why the question was asked in the first place. <S> If I understand correctly, the current derailleur is Tiagra RD-4700 SS , which according to the specs I've found is short cage model: <S> The OP is asking if switching to <S> Tiagra RD-4700 GS (long cage model, <S> according to what I've found) would be the solution to the problem: <S> I'd say: yes, using a longer cage model would solve the problem definitely since the longer cage allows for a longer chain (serving the largest chainrings and sprockets) and takes up more slack of the chain (serving the smallest chainrings and sprockets). <S> I don't own the pictures presented in this post <S> , I've taken them from "the internet" and those particular were found on a ctbike.pl webpage, a bicycle parts retailer I'm not affiliated anyhow, just found them using a well-known search engine. <A> Conventional wisdom is to avoid the big/big and small/small combinations, because of the extreme chain angles. <S> This might well be outdated given more laterally-flexible modern chains, and I certainly do it all the time. <S> But you don't need to, since you have ratios equal or close to the big/big and small/small combinations on the other ring - 52/36 is (almost exactly) 36/25, and 36/11 is (approx) 52/16. <S> So use those, or close equivalents, if you want the gear ratios offered by the big/big and small/small combinations. <S> Go with the longer chain so you can shift into big/big without anything grinding to a halt.
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There are couple of solutions to handle/overcome this issue if your dropouts don't allow it, such as: you can acquire a complete "half-link" chain (they are popular among BMX riders) and be able to break the chain at any length
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Can I run a red light at a T junction? I was wondering if I was on a bike could I run a red light if it is impossible for me to get hit by a car? (Unless the car drives into the bike lane). I made a quick picture on paint to try and show what I mean. EDIT: I live in Washington and here is a picture from google maps, I never see anyone walking on the sidewalk on the side I'm going because it ends in a few meters so usually people jaywalk further back. I also forgot to mention that there is a huge hill after this (for me, I'm not the fittest person in the world) and that's really the only reason I'm asking this because the downhill I get will help me make it up the other hill easier, if it was flat I wouldn't be asking this. Better safe than sorry but because there is a huge hill and I'm not really the best climber I don't want to stop and lose all my momentum to make it up the hill. I also never see any other bikes on the street, just bikes in parks etc. <Q> Unless there are specific local laws or signage saying otherwise, <S> * NO. <S> THE RED LIGHT MEANS STOP. <S> AND IT MEANS EVERYBODY. <S> The traffic lights are there for everybody's safety, not just yours. <S> Pedestrians may be trying to cross, either because they have a green light or because there's nobody coming out of the side-road at the moment. <S> Bicycles turning left from the side-road will be expecting the cycle lane to be clear for them to enter. <S> They're already having to check behind them to make sure no car is either about to turn right across them, taking a wide line round the corner turning left or trying to overtake while turning left, where there isn't room. <S> It's very hard to do that and simultaneously check for people in the cycle lane. <S> I come across this exact situation at the very last junction on my commute into work: it is very dangerous. <S> Also, at a more general level, a lot of motorists believe that cyclists are a bunch of scofflaws who don't deserve respect on the road because they don't obey the law. <S> Motorists disrespecting cyclists is very dangerous for us <S> , so please don't give them any excuse to do it. <S> * <S> Now that an image of the specific junction has been added, I agree with Argenti Aparatus's answer that the absence of a stop line in the cycle lane suggests that local law does say otherwise in this case, and cyclists may go through this red light. <A> Most intersections are stop-on-red. <S> The bike is a road vehicle with rights and responsibilities, and one of those is "not running over other road users" which includes crossing pedestrians. <S> Be a good road user by Stopping on red and stopping on stop. <S> I have a couple of intersections in my city where its clearly marked for the bike lane to go around the lights without stopping. <S> The bike lane goes up to the footpath area behind all the lights. <S> But these tend to be the exception. <S> Do note the double painted stop line for the bikes which don't take the red-painted path. <S> And the cyclist who is exiting the intersection, via the road not the bike path. <S> At speed, the wiggle and change of level is unpleasant and staying on the level road is more comfortable. <S> so I ride straight through on green. <A> I face this sort of junction daily (it's a mirror image as wide drive/ride on the left). <S> While there may be jurisdictions where this is legal, it's certainly not here. <S> I'll assume you've checked for pedestrians crossing and there aren't any. <S> It's certainly foolish. <S> Vehicles can take interesting lines into their lane, especially bigger vehicles that have a hard time seeing and may swing into the bike lane. <S> The two lane junction I pass through like this often has vans sticking into it on the turn, which they take wide before straightening out. <S> This is made worse by the traffic in rush hour squeezing into space that's not theirs. <S> Getting sideswiped is no fun or clipped by a wing mirror. <S> Admittedly this is a rather narrow bike lane <S> but it's perfectly usable when drivers settle into their own lane. <S> In the few cases where the bike lane is protected by something solid rather than just paint, it may bypass the zone controlled by the lights. <S> This should be made clear by signs etc. <S> but you still need to be careful if the lane rejoins the road just after the lights <A> Answering after image of the intersection added. <S> There is no white line across the bike path which implies bicycles are not required to stop BUT you should check your local traffic laws. <S> Large vehicles with large turning circles may intrude into the bike path, or car drivers might go wide and do the same. <S> At the very least you should treat a red light as a stop sign: stop, check for traffic and proceed if clear. <S> Bear in mind the road entering from the left has a right hand curve making seeing approaching traffic difficult. <A> The answer depends entirely on the local laws where you are riding. <S> In most areas cyclist are expected to obey the same traffic laws as vehicles while on the road. <S> Local laws may allow exemptions while in a dedicated bike lane. <A> Yes, but with a small caveat. <S> In Washington, it appears to be legal to ride your bike on the sidewalk. <S> If you mount the sidewalk just before the intersection, ride through during the red, then dismount back into the road, you are not violating any laws. <S> Just don't create a traffic hazard or pedestrian hazard while doing so. <S> Additionally, follow all the usual safety tips when riding on a sidewalk.
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However, if bicycles are not required to stop, you shouldn't ignore the light. Since the laws can vary from city to city we have no way of determining if it legal where you are.
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Rear bicycle rack for car with mini-spoiler I have an Audi A1, which has a small spoiler on the back; it's built into the car, not something I have put on. I have been looking for a bike mount/rack that I can place on the rear of the car. A member of Halfords (popular every-day automobile and bike store in the UK) staff told me that because of the spoiler at the top, there isn't a suitable rack for this type of car. At least not one that they sell. I am aware brand recommendations are a bit off-topic here, but perhaps there is a specific type of rack I need to be searching for? Roof mounted rack is not an option for me unfortunately. <Q> The spoiler does not preclude using a rear mounted rack. <S> I have an Audi hatchbach with a similar spoiler. <S> I use a Yakima King Joe (model discontinued but Yakima and Thule offer functionally equivalent products) which has a wide span between the upper and lower arms. <S> The upper arm sit on the rear glass near the top, or tucked up underneath the spoiler. <S> The lower arm sits below the number plate. <S> YouTube video of installation of the rack on a hatchback: <A> They're probably worried about liability rather than anything else, but it is harder to get something to fit. <S> The gold standard option would be a tow-ball mounted rack, but you need a tow-ball <S> and they're expensive, even if you don't need a trailer socket for a light board (which you almost certainly do, and this can be an issue even with tailgate-mounted racks). <S> Evans have a similar model which they say doesn't fit with spoilers but might fit with yours. <S> Car racks are one of the few bike-related things I'd go to Halfords for by choice, but their stock is limited. <A> As small as your A1 is, a roof rack might be a good option for you. <S> You won't have any issue with the spoiler. <S> The car is short enough that you shouldn't have any issue getting the bike to the roof. <S> If someone behind you isn't paying attention, they'll hit your bumper and not destroy your bike(s). <S> That has the added bonus of leaving you with transportation while the car is getting fixed! <S> As was pointed out in the comments, there is the possible issue of running the bike into something overhead, though I have always been exceedingly conscious of the bike up on the roof. <S> After the first couple of drives, I was never worried about it falling off, I was just very aware of it being there. <S> Also pointed out in the comments <S> was that the OP explicitly excluded this option. <S> I'm leaving the answer because others seem to like it and it may be good advice for someone in the future. <A> If the spoiler is metal a trunk lid style will probably work just fine. <S> They have clips that fit in the slot at the front of the spoiler and take most of the weight. <S> The feet are rubber and you should be able to mount the rack high enough that the straps don't bear on the spoiler. <S> There are straps to the side and bottom of the hatch for positioning, but they do not take much weight. <S> I have a Lexus CT200h that has a metal insert at the front of the spoiler and use this approach. <S> If the front edge of the spoiler is plastic I would be more worried. <S> I also have a Subaru Outback with plastic spoiler and have not tried the rack on it.
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I reckon my old Halfords high mount rear rack would actually fit if adjusted carefully, but they no longer make it. Many rack systems will offer the opportunity to install a roof-top box in addition to the bike racks for more storage capacity (or a place to put stinky riding clothes on the way home).
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Why do rear pannier racks have a raised "nose"? I am tempted to saw off the raised "nose" on my unbranded 2nd hand pannier rack because it's forcing me to lift the child seat substantially, which obviously has implications on stability. But I feel there must be a reason so many racks have this raised nose thing. I had a look at this article , and it hints towards stability/structural integrity, but I cannot see how the nose would help (I'm in engineering but not a structural engineer). My only other thought is that it's an added measure to stop items sliding forward, but it feels like there's something else I'm missing. Does anybody know what the nose is for? Has anyone cut it off and how did that go? NB I purposely avoided using "the F word" ("opposite to rear") to describe where on the rack the nose is - this is meant to avoid this cropping up in searches related to f***t panniers. <Q> I think you are correct that it’s only to prevent items from sliding forward and falling off or colliding with your legs/hips. <S> This is only really important if you use the spring loaded clamp. <S> A lot of racks (I think all of them without the spring loaded clamp) don’t have this “nose”. <S> Since there is still another horizontal bar right below it <S> I don’t think removing it will affect stability. <S> Just make sure to cut it cleanly, remove any burrs, plug the hole and apply some paint to prevent rust. <A> Pesonally I'd replace the rack. <S> When using a Hamax Siesta child seat I fitted a Tortec Velocity Hybrid rack. <S> In your specific case though, given that there's a cross-brace at the bottom of the part you want to cut off, you'd be fine to cut it. <S> If you later want to put items on top of the rack, tie a bungee cord to the front and hook it at the back. <S> If you're really worried about the high centre of mass, doing away with the rack would help -- but I assume you need it. <S> It may be possible to make the rack sit lower if you remove the mudguard and build a new mudguard around the rack. <S> Here are some hints . <S> The rack itself may have an extra set of holes or may need modifying. <S> A tip for you when you lower the seat: it will flex more than you think, and the seat banging into the rack is annoying for you and your passenger. <S> Keep a bit of clearance and/or strap some foam padding to the rack. <A> Thank you all for your responses. <S> I'll show you what I've done but let me just mention that I put the Solution mark on Criggie's because it seems to address my considerations best - but all responses and comments so far were very useful. <S> As some of you have spotted, the seat blocks any useful access to the rack, so I just took the rack off. <S> I then lowered the bracket - I will record my steps in case it's of any use to someone. <S> The frame has an eyelet for the brake cable, and my initial plan was to saw the eyelet off or file it down - by that point, I hadn't even considered where the child seat's rods would go, and that they would clash with the rack. <S> I then noticed I could just about squeeze the bracket between the eyelet and the joint where the top stay is welded to the seat tube - see photos in OP. <S> Only then did I notice the clash with the rack - but it didn't seem necessary to include this part of the story in the OP. <S> The eyelet wasn't an issue in the end: the seat is an Aldi Bikemate, and the bracket has a gap which fits the eyelet perfectly. <S> The seat tube by itself is too thin for the bracket, but when I added a slice of an old tyre between the black plastic front part of the bracket, the bracket sits securely. <S> The eyelet is perfectly sandwiched between the two parts of the bracket and the Bikemate's rods which clip into the bracket. <S> The opening in the rubber "wings" is slightly "shorter" than the opening in the metal back of the bracket, but wraps around the eyelet nicely - I just had to "widen" it a touch with a retractable knife - see the red lines in the photo. <S> I'm really pleased with how it all fits - much better than squeezing the bracket between the weld and the eyelet. <S> The old brake wire needed replacing anyway so that worked out ok. <S> The position of the noodle is not perfect - it's pointed down, but the casing is not as tight as it might look. <S> I just need to trim and cap the brake wire in another session... <S> Thank you all once again for your help, if anyone has any questions please just ask. <A> It is to stop the load sliding forward under braking, or even from the pressure of the clamp (?) <S> part of the rack. <S> If it were left to the seat post, that's one round post and not a wider ledge for support <S> Suspect <S> this is more of a side benefit. <S> Personally I really dislike when things touch my legs while riding, like the end of the brake cable or a light fitting, or any part of the load. <S> On the downsides, the lippy bit makes larger items a bit harder to put flat on the rack. <S> It also adds a tiny bit of weight and aero drag. <S> Separately, having the load a bit further back increases weight on the rear wheel which moves the weight distribution aft, and this contributes to making the front tyre more lifty on a climb. <S> If you cut off the lip, you'd probably have to add some flatter bracing. <S> To get the kids seat to work better, consider removing the rack completely for as long as you need the seat. <S> If you need to move something, then put the load into the kid's seat. <S> This will also increase the overall riding stability because the child will be a bit lower.
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It also provides a wider part into which the rack can push the item firmly. Also, if you're a bungee user then it provides a higher point with corners to hook onto, so the hooks are less likely to slide.
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Is it possible to convert a single speed rear wheel into a multi-speed rear wheel? If I buy a wheelset that was meant for a single speed bicycle, how could I convert that wheelset to a multi-speed bicycle? Note that I am not asking about converting a fixie ride into a multi speed one, I only care about the wheels. Tutorials and video links are welcome! <Q> Conventional wire spoked wheels don't allow this. <S> All types of conventional singlespeed hub (BMX, cassette, freewheel, track, coaster) take advantage of their one-cog-ness to have center-to-flange measurements that are either symmetrical or close to it, creating a wheel with no or almost no spoke tension disparity, which makes it stronger and more robust. <S> (Non-flip-flop track and all disc singlespeed hubs do give some spoke tension disparity, but not much.) <S> Such a hub offers no space to put a gear cluster. <S> Certain disc and mag wheelsets are switchable from track to multi-speed hub guts. <S> They're not subject to the above limitations as their structure is closer to only existing in one plane. <S> To do it you're buying the manufacturer's parts and following their procedures. <S> Zipp 900s are a current example, allowing riders to use the same big money disc for both track and TT/tri. <A> No. <S> Not in any practical sense. <S> Single speed hubs cannot be converted to multi speed. <S> You'd have to swap the hub out in which case you might as well buy a multispeed wheel in the first place. <A> You want to use a track wheelset as a "multispeed rear wheel" <S> First problem is the Over Locknut Dimension/Distance of the wheels and the spacing of the frame. <S> A track wheel will probably have an OLD of 120mm, the horizontal distance between the outsides of the two locknuts. <S> This should be the same as the space between the rear dropouts on your frame. <S> If your frame was for a multispeed bike, it could be 126mm, 130mm, 135mm, or a lot more. <S> This distance scales approximately with age. <S> A 130mm OLD could have been an 8/9/10 speed, and a 126mm might have been a 5/6/7 speed cassette. <S> If the OLD doesn't match you might be able to compress <S> / bend / cold set the frame to fit. <S> But squashing one up evenly is a lot harder than expanding an old frame. <S> Frame must be steel to do this - an aluminium or carbon or titanium bike <S> will not cold-set. <S> You might also get away with adding some spacers to the outside of the wheel's axle, but it will be inherently weaker because of the unsupported length of axle. <S> I did this to get a 130mm wheel in a 135mm frame temporarily, and the axle bent within a month. <S> Another option is to get multiple speeds by running an internally geared hub. <S> Downside is this is significantly expensive and requires a full rear wheel rebuild. <S> A Rohloff starts at 135mm wide, but offers 14 gears. <S> If your frame is 120mm OLD (ie its a track frame) then you have some options but fewer gears. <S> These are 3-5 gears. <S> Sturmey Archer SRF3 (118.9 mm OLD) <S> SRAM Spectro T3 (117 mm OLD) Sturmey Archer XRF5 (119.7 mm OLD) <S> From http://www.hubgear.net/table.html <S> A good resource there. <S> Regardless of your chosen solution, there is no cheap/affordable way to do this well. <S> If you really want gears, buy a bike with gears and keep your existing one for whatever riding suits it.
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Aerospoke also is/was switchable, and were pretty common in their heyday, so probably represent the most popular singlespeed wheelset you can buy and then convert later to derailer use.
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44 622 / 700x45c what tyres to buy? The marking on the existing tyre to replace is 44 622 /700x45c On sites like https://www.schwalbe.com/en/groessenbezeichnung.html 44 622 corresponds to 700x42c and 47 622 corresponds to 700x45c , I am confused which number to trust and 44 622 also looks like rare tyre size as I can't seem to find any in UK. Also how strict are these numbers +-1 size jump going to render me unable to put tyre on? <Q> Some of the confusion relates to the fact that there are different but equivalent ways to measure tire sizes. <S> The first tire measurement you mentioned 44 622 refers to the tire width of 44 mm and rim bead seat diameter of 622 mm respectively. <S> The second measurement type (700x45c) is a 45 mm wide tire that also fits on a rim with a 622 mm bead seat diameter, the 700c is an old French sizing nomenclature based on the final external diameter being 700 mm for width class of tire (e.g., a, b, c widths). <S> (The final outside diameter is affected by the widths, so the three widths would have different bead seat diameters in order to get a final diameter of 700 mm). <S> The differences in tire widths you are seeing (i.e., 42, 44, 45, 47) likely corresponds to the fact <S> One standard may assume one rim width, while another standard likely assumes a different rim width. <S> In the end none of these nuances matter much as a frame that can clear a 700x42 tire will also likely clear a slightly wider tire (e.g., 700x47). <A> Schwalbe do something a bit odd, as you've spotted. <S> The widths of the same tyre don't match for the different numbering systems for some of their tyres. <S> I believe this is the ones with thick, stiff layers of picture protection under the tread, which would make them take a different shape to a simpler tyre, further from a perfect torus. <S> Unless you're extremely tight for clearance, it doesn't matter. <S> If you are that tight, the same nominal size from a different brand or even style would need a test fit. <S> Example: I've run anything from 700x28 to studded 700x38 on my hybrid; the later needed some fiddling with the mudguard to fit. <A> You should be fine. <S> A long time ago in France, wheels were measured by the diameter in mm over the tire <S> and you had size 700, 650, all the way down to 400 on kids bike. <S> There were also different widths, so they went 700A through 700D from narrowest to widest. <S> This system is great if you are trying to figure out if your fenders are going to fit around the tire, but terrible if you are trying to match tires against rims, because a skinny 700A is going to not be very tall and thus have a larger diameter rim than the balloony 700D. <S> And rim diameter is what matters most for tire compatibility. <S> Over time most of the other sizes went extinct except for the 700C and 650B. Other countries all had their own ways of measuring. <S> The real way to tell if it matches is to measure the diameter where the tire meets the rim . <S> That is your 622 number. <S> Most shops will be calling it by the 700C, not the 622, but if you get them is will say 700C in ink, but 622 in the raised letters. <S> Don't worry. <S> That rim diameter is extremely popular . <S> The smaller number is the tire width. <S> That's less important and everyone measures it a bitt differently.
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the final tire diameter depends on the combination of tire and rim widths (i.e., the same tire can have different final widths depending on the rim width it is mounted to). What really matters is that all of these must be fitted to a wheel with a bead seat diameter of 622 mm, which is the diameter used on your bike.
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Just curious what DIY setups have worked for removing crown race from a steerer tube? I have a great solution for installing a crown race with just plain PVC pipe, but am really flummoxed as to how to remove a crown race from carbon forks without purchasing a specialized tool or driving 30 miles to my closest bike shop? Any DIYers out there that have found a consistently workable solution? One that does not involve flat-blade screwdrivers... <Q> A method I've never loved but have used a time or two and seen others use a lot is an old disembodied pocket knife blade and a hammer. <S> Carefully tap it in along the spine at multiple spots to wedge off the crown race. <S> This method does work well, including on forks that offer zero overhang of the crown, but it has some risk of cosmetic damage in the best case, and on a carbon crown I'd worry it might be capable of doing more. <S> You could mitigate that risk by using a thinner blade, probably. <S> I kind of hate the idea of using this approach on an all-carbon fork (as opposed to an aluminum crown), but the truth is that proper tools work on a pretty similar principle in these days of zero crown overhang being common, and themselves are not totally free of any risk of damage even if used carefully, so it may not be as stupid as it seems. <S> On an aluminum crown you can do it all day as long as you don't care if it looks pristine. <A> It's very similar to a generic bearing splitter. <S> So yes, it's a specialized tool, but not a crazy-expensive one, especially considering you could ruin your fork if you did it wrong. <S> There's another type of tool that looks like an oversized tuning fork, where you invert the fork, remove the wheel, and set the "blades" of the tuning fork on (what is normally) <S> the underside of the crown race, and tap it in the center, in line with the steerer tube. <S> This would be fairly easy to improvise using wood if you're handy. <S> Caveat: <S> I haven't tried this, I'm just spitballing. <A> Here are a couple of suggestions, but as you are dealing with carbon not sure I recommend them. <S> Box knife blades - stacked together <S> so you get the shape bit under the crown race and can walk it up. <S> Heat - with carbon use extreme care. <S> Rather than a heat gun, a hair dryer and bring it up to a temperature no hotter than you can still touch. <S> The crown race will expand and loosen.
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There is a relatively cheap kind of crown-race removal tool that acts as a set of wedges that clamp down on opposite sides of the race to drive it away from the crown.
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Marin Fairfax Alp 2011 - Can I fit a 11-32t Cassette I currently have a Shimano LG50 12-25t 8 speed cassette and am finding it a real struggle on steep hills - I am around 13 stone (82kg). This is the first time I have looked at changing the original gear ratios on any bike I have owned. I want to change to the 11-32t or another cassette but I am wondering if I need a new chain i.e. to lengthen it and also if the rear mech is OK. I ask this as stuff on the interweb says both can possibly be an issue. I believe there may be normal and long leg versions. The rear derailleur is the original Shimano Sora 8 Speed Rear Derailleur (GS Long Cage). Current chain is the Shimano Altus HG40 6-7-8 Speed Chain. Crankset is Truvativ Touro 52-42-30t. Using the link below it says the rear derailleur will take 37T to 39T or less.So the current cassette is (25-12) + (52-30) =35T11-28 is (28-11) + (52-30) = 39T11-30 is (30-11) + (52-30) = 41T11-32 is (32-11) + (52-30) = 43T From this it looks like my only option is the 11-28, which would only give a minimal improvement. Am i wasting my time trying to fix this particular bike as it stands????? Thanks in anticipation. Kev Many thanks to you all for your responses. I hope I have learnt a lot around this area and it sounds like I was hoping to achieve too much. I have ordered a 11-28t cassette and new chain as this stays within the guidelines from Shimano for the Sora rear mech. I will be v interested to see the difference it makes. As suggested by someone, I did a lot of shopping around for a slightly smaller 5 bolt chain ring than the 30T that's on there, but hit a massive blank in finding a Truvativ ring that was smaller. Thanks again to all......UR*s <Q> I think a disadvantage of the 11-32 cassette are the large gear steps. <S> Also consider that switching from 25 to 28 already makes it 12% easier. <S> You could (additionally) install smaller chainrings, 52 is quite large and instead of 30 you could go down to 28 or 24. <S> You will need a new (longer) chain if you increase cog size, unless you decrease chainring size at the same time or the chain is currently a bit longer than necessary. <S> A worn chain will work badly on new cogs or chainrings though. <A> Yes, you would need a longer chain. <S> Depending on how confident you are in your ability to avoid using the "wrong" gears, you can take derailleur chain-wrap capacity guidelines with a grain of salt. <S> You never need to be in the 30/11 or 52/30 combinations, as those ratios are reproduced with other gear combinations, and it's generally preferable to avoid cross-chaining <S> anyhow (going big-big or little-little). <S> You could try getting a new chain and cassette and seeing how it works; if it doesn't work, you'd need to get a new rear derailleur. <S> I'm a little unclear on the compatibility, but the Sora group has been upgraded to 9-speed, <S> so I think you'd need to get a Claris derailleur instead <S> (I'm happy to be corrected on this point). <S> The current Claris long-cage does have 43 teeth of wrap. <A> Total capacity (difference in sprocket tooth counts plus difference in chainring tooth counts). <S> For a 9 speed Sora RD-3300 GS (Source: [Shimano 2004-5 Line Up Chart][1]) <S> : Max sprocket size = 27 Min sprocket size = 11 Total capacity = <S> 37 <S> So technically you are exceeding the max sprocket size. <S> You need a total capacity of (52-30) + (32-11) = 43. <S> That's well in excess of the spec. <S> Yes, you could try to avoid the big ring - big sprocket combination but sooner or later you will try to change to that combination and possibly rip the derailleur off. <S> Basically, older, less expensive bikes with 7 and 8 speed systems used a derailleur designed to work with a narrower cassette range, and got wider spread of ratios with a triple chainring crank, so they are not up-gradeable to bigger cassettes <S> If you want lower ratios, look at replacing the chainrings for a smaller set. <S> , perhaps 48-36-26 instead of your big 52-42-30. <S> I think you might need a new crank to do this as I believe the Truvativ Touro is <S> 130mm BCD. <S> Triple cranks are not expensive though.
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If you has a narrower range of chainrings I'd say you could get away with the larger cassette sprocket, but the required total capacity really rules it out. The things you need to take into account are the rear derailleur's Max sprocket size Min sprocket size
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Will yellow glasses stop me being blinded? Will yellow glasses stop me being blinded ? In the winter I commute along a canal path, the lights from the other cyclists are blinding at times. Will yellow glasses stop this, it's too dark for normal sunglasses? <Q> No. <S> What blinds you is the relative brightness of the bike lights and the fact that unlike legal car lights, many of them are pointing straight at your face. <S> They work by blocking blue light, which is scattered so that it comes from all directions and makes shadows less visible. <S> EDIT: <S> The spectrum of most white LEDs does have an intense spike at blue wavelength. <S> Most of the energy is still at longer wavelengths, where yellow glasses do not do much. <S> They will also filter your own headlight and street lights if they are white LED variety. <S> Because of Purkinje effect , the blue part of spectrum is more important for low light vision. <S> This is why white LEDs seem disproportionately bright and why yellow glasses restrict your vision more in dark than during the day. <A> Maybe. <S> Some manufacturers of these kinds of glasses claim that their products can help reduce glares from other cars using LED headlights. <S> I'm not sure how much blue light it filters out. <S> It's the blue rich LEDs that are more blinding. <S> Some LEDs are better at preserving our night vision such as warm white, yellow, orange, and red. <S> Warmer colours, blue blocking glasses would affect your's less since there's less blue light. <S> More options for warm white LED headlights are online. <S> You can also make one. <S> This may give you more time to react when animals or people cross the road right in front of you especially when poorly lit. <S> If you're using yellow glasses, make sure that some blue light is allowed to pass through as you need to be able to see police car flashers. <S> Also, regular blue blockers can reduce cyan light, making green traffic lights appear dimmer. <S> Green traffic lights seem to use cyan LEDs. <A> They produce a definite yellow tint to everything. <S> In addition car windows look extra yellow at some angles, because they are reflecting the blue sky. <S> Downsides, having a second layer of translucent material means two more surface boundaries for light to refract, so there's a distinct drop in optical clarity. <S> This could be resolved by using a thin film attached directly to the lenses. <S> The clipons I were using as a test were plain plastic, and were not particularly expensive <S> so I wonder if they have a lot of microscratches and haze already, which would also drop the quality of seeing through. <S> It also added a noticeable amount of weight on the nose bridge, which was uncomfortable. <S> I could see around the sides using peripheral vision, which was somewhat disconcerting but I got used to that. <S> On the upside, I'm confident that an oncoming car headlight's glare was reduced somewhat, but the drop in acuity more than weighed up against that. <S> ANSWER: <S> Its a definite maybe. <S> Ttry it and see for yourself in your situation.
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The nice thing is that your own headlight's reflections would be less blinding so that you can see unlit areas better. The yellow lenses are designed to increase contrast in daylight. I've been trying some yellow clip-ons which mount to the front of my glasses.
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New bike for commuting and touring I went downstairs earlier to get ready for an afternoon ride on the cheap bike I picked up a few months ago as I wasn't certain if I would keep the cycling up and found to my dismay that, once again, the rear wheel had come loose on the bearing and was wobbling back and forth. I've been thinking about replacing it since I have kept up the cycling successfully but there's too much information out there for me to make sense of and certain concerns that I don't know how to quantify; but first, I'll put what I'm after. £1000 budget Road type split: 90% tarmac, 7% gravel cycle path, 3% horrible rutted gravel road Commuting 15k each way Would be used for occasional long distance cycle rides (Think London to Amsterdam style challenges) Rugged/Low maintenance 24 speeds preferred (If this is just me being too used to MTBs from my childhood, please let me know) Drop bars preferred Proper gear shifters that click into place instead of moving a lever and hoping preferred Sized for 6'0", 33" inside leg Capable of carrying a fat sod who weighs ~100kg (for now) Normally, I would consider just replacing the wheels with higher quality ones but I think that the bike I have is a size smaller than it should be as I have to have the seat at its maximum height, my legs still aren't fully straight at the lowest point of the pedal and the handlebars won't come high enough for me to take advantage of the drops. On top of that, I prefer airless tyres as I've historically had terrible luck when it came to punctures and am crap at fixing them. My concerns stem from various throwaway comments such as the review here under disadvantages where the reviewer raises concerns about nuts and bolts falling off. More experienced riders than myself have commented that airless tyres feel like 115-125psi which can only exacerbate the problem. As you can probably tell from the "crap at fixing punctures comment" earlier, I'm not a confident tinkerer - while I know where most of the important bits fit together, that's mainly on a theoretical level and getting out allen keys/spanners is something I view with dread. After all that context, my specific questions are below: Does anything spring to mind that fits the above requirements like a glove? Failing that, does anything spring to mind that fits all but one of the above requirements? If neither of the above, what should I look for to ensure that the bike is going to fall apart the minimal amount? Is there such a thing as a bike made from disparate components, where components are all purchased separately like if you were building your own PC? On a slightly different note, as a large chain of stores, is Halfords trustworthy or the PC world of cycling? - I have a LBS near me but their opening hours are almost entirely the same as the hours I work making life a bit tricky. And once I own said new bike Does cycling on horrible rutted gravel roads or even smooth gravel cycle paths harm road bikes considerably? Bike weight doesn't bother me that much currently - I'd rather something be overbuilt than constantly be worrying about it. Finally, I wouldn't be entirely surprised if my requirements list is incompatible with the budget.Thanks all, Ben <Q> Last year I bought a steel tourer. <S> It seems to tick all your boxes or near enough: £900, 27 speed, pretty rugged ( timelapse of a ride I did last year , starting when I hit the gravel, before it got rough), and I can also do 300km days on road. <S> I weigh less than you but then more than make up the difference on some trips. <S> A tourer's not your only option. <S> Cyclocross bikes and adventure road bikes (the 3 categories overlap anyway) will also do it <S> but I wanted to be able to carry a lot, and you might do too. <S> You may want to swap tyres between rough gravelly stuff and serious distance. <S> The combination of a heavy rider, potentially crashing through potholes (though I could be maligning you there) and a light road bike isn't a good one, which is a reason to go for a sturdier frame. <S> I'd steer clear of Halfords both because they don't have much range and because I've been unimpressed with their ability to sell bikes that actually fit the rider -- fit is important here as you want long rides, and drop bars make for a less forgiving fit IMO. <S> Mine came from Evans, but an independent local bike shop can often get similar pricing, and would have more chance of tweaking the spec if necessary. <S> When it comes to tyres, I suggest going for tough touring tyres, with a Kevlar belt. <S> I run that sort of thing on my top 2 bikes by mileage, and I don't think I've had a puncture this year (over 8000km). <S> As you appear to be in the UK, do you have access to a bike-to-work scheme? <S> Is that where your £1000 comes from? <A> Specific product recommendations are off topic here, but some general answers. <S> There are putatively ‘road adventure’ bikes that run 28-35mm tires that will deal with tarmac and gravel. <S> However, a road bike will not fare well on poor, rutted and potholed surfaces. <S> Forget the idea of ‘airless’ solid tires. <S> Those are not seen on bicycles for good reasons. <S> Puncture resistant tubed tires are available, also ‘tubeless’ tires that run with sealant inside that seals small leaks. <S> Yes, you can have a custom bike built but it will be very expensive. <S> but it’s <S> still expensive and obviously not for you. <A> The 10% gravel suggests that you may be looking for a 'gravel' type of bike. <S> They have drop bars, they have various holes for attaching panniers, mudguards and bikepacking. <S> You should be able to do London to AMS on such a bike <S> and it's going to perform pretty well for your daily commute <S> if you fit it with wider, perhaps tubeless tyres.1k budget should afford you at least a carbon fork and ideally a carbon frame as well, to reduce vibration from the road. <S> Later on you can upgrade the wheels etc.
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A ‘gravel’ bike with 40mm plus tire will be better but will be compromised on paved road surfaces. You can buy individual components and build a bike yourself
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What can I get for panniers to commute with my 17" laptop? I have looked for a pannier that can hold my 17" laptop for a couple of years. No such thing exists. I tried contacting a couple of places to make one, but they never replied. So, now I'm trying to make or combine things to get myself a rain-safe pannier for my laptop. Are there any ideas on what I can use? Here are the details of what I've got to work with. My laptop dimensions: 17" screen 16.5" x 11" x 1.5" dimensions. I bought an Arkel Cam Lock Hook Kit 10" . That looked like a great way to attach a bag to my rack whether I use an existing bag or somehow make my own bag. I also have a couple of laptop sleeves I got thinking I could put the laptop in a larger pannier in the sleeve. The sleeves ended up only protecting against scratches. The panniers I tested all stretched to leave room for the laptop, but the laptop corners were left very vulnerable with almost no protection. I have a Specialized 2011 Globe Haul 1. The rack is built-in and can hold up to 50kg (110 lbs). As the bike is designed to haul so much, the bike was geared very low when I bought it. I had an additional gear added to the front sprocket so I could ride better when going down hills. Even so, this is very decidedly a commuter bike, not a speedy racing/road bike. What I have been using: I was strapping a laptop backpack on the rack (on top) with bungee cords, but the backpack is worn out. I'm afraid of getting caught in some Dallas rain, in which my backpack, with ripped sides and broken zipper, can't protect my laptop. Also, I had a really hard time strapping my lunch on with my backpack, and I sometimes avoided riding because it took awhile to get everything strapped on, so I'd like a pannier that makes it fast to get loaded and off riding. I will not wear a backpack or a messenger bag, but I'd be happy to modify something so I can use it as a pannier. I've got analysis paralysis so I'm reaching out for recommendations on what to use. On vibration: I have one SSD and one standard hard disk. When I bought replacement disks, the new ones were thinner than the old, so I used some spare foam (static safe black foam for packing electronics in) to keep the drives in place. As such the drives actually have some cushion just for themselves). <Q> Having a 17" laptop does limit your options. <S> If I understand it correctly, you want to carry your laptop on your bike (not on your body), in a bag that gives it some impact protection. <S> If you feel handy and are willing to throw some money at the problem, I'd recommend getting a hard-shell case filled with egg-crate foam, drilling holes in the case to install that Arkel mounting kit (or a different mounting kit), and sealing the holes with silicone caulk. <A> Ortlieb make a "back-roller" in heavy vinyl that has a roll-top and a quick mount system. <S> Basically you grab the loop on top, it detaches the grabs that attach to the top of the rack <S> and it comes away. <S> A hook secures the bottom of the pannier to the lower part of the rack so it cannot flap up and down as you ride, pivoting on the top of the rack (though it will if you do not adjust that hook and make sure it is engaged). <S> I rode with a few models of the old MacBook Pro 17" in one of these panniers and had plenty of room to keep the computer inside various padded sleeves for extra protection. <S> Even with a huge computer in a padded bag there is enough room for a basic change of clothes. <S> It is absolutely waterproof and even has a nice reflective patch on both front and back of the pannier. <S> I still have the panniers as they will work with most bike racks, though I am using a backpack since I found one with a good suspension system that doesn't lead to sweaty back. <S> There are many options for 17" computers and I have a couple but the classic pannier is the most versatile. <S> Can't imagine this not working unless you are carrying a machine where "portable" is an optimistic label. <S> addition: don't be misled by the measurement given for the bottom of a flexible pannier with flat panel sides - those sides easily extend to accommodate the 11"+ width of a 17" laptop in a bag. <S> The only way to know for sure is try it. <A> Would a sturdy laptop bag combined with one of those solutions be an option for you? <S> https://bicycles.stackexchange.com/a/54936/34697
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I did a little poking around and found a well-known hard-shell case brand that does have briefcases for 17" laptops.
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I'm looking for a part that connects the saddle to the body frame of the bicycle I recently removed the saddle because it was squeaking a lot, then I cleaned the inside and put oil back in, however I couldn't re-attach the bar under the seat to the body frame, then I used this clamp probably in the wrong place and then the hex bolt threaded so I can't get it off. The bike is a Carrera Subway 2. I should get a new seat anyway, but how can I attach a new saddle and bar thing to the body frame? I don't know what's supposed to screw into here to hold the bar and the saddle in place. <Q> Its a bit unclear what you did or what the problem is. <S> I presume you are having problems reinserting the seat post into the frame. <S> From the above diagram, the seat post slots into the seat tube, and is held in place by the seat post clamp (not labeled). <S> I also presume hex bolt 'threaded' means you cannot undo the bolt in the seat post clamp. <S> This clamp has to come off to insert the seat post. <S> A bit of heat might help. <S> However if the bolt is tight I would not bother. <S> If that does not work you should be able to cut the bolt with a hack saw blade in the slot, and remove the clamp. <S> An alternate is to drill the bolt head off or cut the clamp itself. <S> New clamps are readily available <S> so do not worry if you damage it. <S> Once the clamp is off, the seat post should slide fairly easily into the frame, set the height and tighten the new clamp (not too much). <A> I dare to suggest that the OP has a suspension seat post and the squeaks were the sounds of the suspension. <S> From the picture attached I see that the seat post probably never left the seat tube. <S> It would help us greatly if you add a picture of the other part referred as "the bar under the seat", or even better - all the elements disassembled. <A> Re: I cleaned the inside and put oil back in <S> You should not use liquid oil between the seat post a frame. <S> Use a very thin coating of good quality grease, or better yet a specific bicycle anti-seize compound that will prevent creaks and stop the seat post sticking in the seat tube. <S> You may also want to check the tightness of the bolts securing the seat post to the saddle rails as these can be a source of creaks too.
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Most likely the suspension seat post needs to be reassembled. My first attempt would be to try to knock it off with a hammer and screw driver by tapping gently around the circumference and 'walking' it up the seat tube.
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Modification for cycling with one functioning hand My dad loves cycling, however he has dystonia which reduces control of the muscles in his hands. He can still cycle, however this becomes very painful after a moderate period of time due to gripping the handlebars, and also reduces his control of the bikes movement. An answer related to this question advises the use of a steering damper to help with stabilisation, however I was also wondering if anyone knew where I would be able to buy something like this: My dads right arm is better than his left, and he still has control in his forearms, so if possible the device would allow him to steer using his forearms. Any help would be appreciated. <Q> So I don't know much about the disease you mentioned - but if the symptoms are caused by the strain on the wrists and hands, then I have a perfect but expensive solution: Switch to a recumbent. <S> There is no weight on the hands, ever, on all recumbent types. <S> Under seat steering handlebars allow the hands to rest next to the torso in a very relaxed fashion and <S> pretty much straight, like hanging down beside the torso except the whole arms are angled somewhat towards to front. <S> Above seat steering handlebars probably allow for more variations on the grip, but I think the posture is overall slightly less relaxed, you can't let the arms just hang down as much. <S> I'm pretty sure all of those types also exist in three wheeled versions if the disease further progresses and makes balancing too hard. <A> You should have a look at this: http://www.notbroken.co.uk/ <S> The Founder ( Tom Wheeler ) had a massive crash while riding downhill and can't use his right hand properly. <S> He adapted his bikes and with the help of 3D Printing he is now making his own stuff to be able to ride again. <S> I think you can shoot him a mail and see if he is able to help with some tips or stuff. <A> Not exactly what you are after, but a set of clip on aero bars would provide basic control with the forearms for changing road position and gentle curves. <S> Although depending on flexibility it might not be possible to find a comfortable position.
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Center steering recumbents with no handlebars (or handlebars not used for steering but only to mount brake handles) don't need any arms at all (well, if you mount coaster brakes), but more control of the rest of the body and are probably harder to ride.
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What is best for your brakes when stopping at the bottom of the hill? You are at the top of a hill and want to stop at the bottom. What is best for your brakes so you don't wear them down: brake continuously; or brake when you reach the bottom? <Q> In terms of wearing out the brakes, they will wear less when you brake at the bottom. <S> When you descend a hill you have a fixed amount of energy to lose, and when you descend at a higher speed, a larger proportion of that energy is lost to wind resistance. <S> Practically however, brake pads/blocks tend to last a long time and are cheap to replace, wear is not really something to consider too much. <S> It's better to descend safely at a speed you feel comfortable with. <A> One should not trade their safety for prolonging brake pads life. <S> Thus gaining the speed and hoping to lose it at the very end of the ride is not the wisest thing to do. <S> Having said that the question is rather whether to: lightly but constantly brake maintaining more or less constant speed; or gain some speed, brake hard, repeat <S> I'd opt for the latter since it allows the rims or discs to cool down thus having them ready and at considerable efficiency should you suddenly need them. <S> Furthermore, you can analyse the evolution of the roller brakes - the latter the generation the larger the radiator for the drum - it was observed that on longer descends when the brakes were partly engaged, they did overheat and lose their braking capability. <S> With larger radiators they did overheat, much later (if ever) though. <A> There are really two optimal solutions: Go as fast as you dare , perhaps slightly braking, maximize your frontal area (thereby maximizing air resistance) <S> then brake at the end quickly. <S> The idea here is that you are obtaining part of the braking force from air resistance due to the maximized frontal area and maximized speed. <S> Go very, very slowly, braking all the time . <S> The idea here is that the slower you descend, the less the braking power needed is. <S> Power is force times velocity; force stays the same for a given hill, but velocity is something you can affect. <S> Because braking power is lower, the heat dissipation required per unit time is lower, and thus, brake temperature is lower. <S> The interim solution, by continuously braking at an intermediate speed, a speed at which air resistance isn't major braking factor but a speed at which the brakes are heated above the boiling point of water is the problematic strategy. <S> It can cause very fast brake pad wear. <S> Depends on the hill which of there strategies should be used. <S> The problem with the first one is that if the hill is very steep, chances are you may not descend at a speed that would offer good air resistance to dissipate majority of the energy. <S> So, you have to estimate if you dare to choose the first strategy. <S> And remember to use both front and rear brakes so that you have more heat dissipation capacity. <A> This question is about whether you should execute the bicycle equivalent of a suicide burn. <S> For a rocket this means sparing fuel, for your brakes this means producing less heat. <S> Do note that the name doesn't come from nowhere. <S> It's too dangerous to depend on your maximum thrust to not slam into an hard object like the Moon at highway speeds, rockets generally do control their rate of descent early on. <S> The other consideration is that your brakes are much better at dissipating when not in contact with the disc, so even if you brake early, it's better to break harder but not continuously. <A> Some modern disc brake systems feature special cooling fins to keep the temperatures in check. <S> Greater speeds cause improved flow of air around these fins, thus improving their ability to dissipate heat. <S> Letting your speed grow until you apply the brakes cools them down, whereas constantly applying them a bit would result in constant heat generation without the same cooling benefits. <S> Basically all the heat your brakes generate must be dissipated to the air around your bike, so this applies to brakes without these fins too, although it's far more noticeable with the fins. <S> I recommend braking down whenever you feel you're about to go too fast for your own comfort, then letting go of the brakes for a while and repeating this until you're at the bottom.
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It is faster and more energy-efficient to brake as hard as you can as late as possible than to control your speed early.
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How to be certain a Boardman ADV 8.8 would fit without prior road bike experience? I'm looking to buy my first road bike - an adventure/gravel road bike. Question: How can I be certain it's okay or not? And should I be looking for a bike that's closer to my estimated frame requirements, and with ideal clearance/reach? Background information: I went to Halfords today and rode a Boardman ADV 8.8 (size large, 55.5cm) around the store. It's great value for a 10.5kg gravel bike. I'm a 5 ft 11 male with a 34 inch in leg size. So using the livestrong calculator apparently best for me is 57.86 frame size & 76.26 saddle height. I loved the bike but i wasn't sure whether it was too small - specifically, i'm referring to the efficiency/comfort of my leg rotation/angles on the pedals. It felt like my legs were coming too high up and meeting some resistance from myself. So the staff raised the seat more and it became noticeably easier. The staff didn't want to keep raising the seat saying the bending down could become uncomfortable. Whilst with 1 1/2 / 2 inches of standing clearance between the bar and the crotch, they worried an XL would be too high and I wouldn't have enough reach. I'm not sure whether it just feels new and different compared to conventional cheap hybrid bikes i've been used to, or whether there's a problem. It is obviously smaller than my estimated frame requirement, but apparently the XL wouldn't work (reach & clearance). So the question: How can I be certain it's okay or not? And should I be looking for a bike that's closer to my estimated frame requirements, and with ideal clearance/reach? Thanks for any advice. <Q> This is why people recommend not going to Halfords. <S> (For the benefit of people outside the UK, Halfords is primarily a car accessory shop, which also sells bikes). <S> If you go to a proper bike shop, the staff will insist on fitting the bike to your properly, rather than coming up with excuses not to. <S> They'll also let you take the bike on a proper test ride, rather than just riding around the store. <A> Answering 'How to be certain if a <insert bike model here> would fit without prior road bike experience? <S> If going to a store like Halfords, it's a good idea to arm yourself with some general bike fit knowledge. <S> It's relatively easy to find that online. <S> You probably will feel a bit 'bunched up' and that your knees are coming up too far if this if your first drop bar bike and you are used to hybrids with a more upright riding position. <S> Know how to ballpark the seat height: heel should touch pedal with butt on the seat and leg straight. <S> When seated you should be able to get toes on the ground. <S> It's good to set the saddle fore-aft position too if they will let you: line from kneecap to pedal axle should be vertical. <S> You then look at what angle your torso and arms are at when on the tops, hoods and drops. <S> More leant forward is more aggressive. <S> (Commenters, please feel free to add better advice if you feel I'm off base here). <S> It helps to have a friend with you to eyeball the angles while you are sitting on the bike. <S> Remember that you can swap out the stem to make a couple of centimeters of adjustment in hand position. <A> There is a lot of psuedo-science (and granted, some real science) around bike fit. <S> My experience is this - there is a LOT of adjustment available through seatposts, saddles, stems and bars that means that the actual frame itself is not as critical as people would like to make out. <S> If you look at the bikes ridden professionally, they often have pretty extreme setups that nobody would buy "new" from a shop. <S> This is because, fundamentally, everyone is different. <S> I would suggest buying a frame size you won't regret. <S> And basically for me, that is standover height (flat-footed). <S> If I'm going to squash my particulars every time I have to get off the saddle at a junction, I'm not going to enjoy the bike. <S> I'm inclined to go with the size that Halfords suggested. <S> The XL may be uncomfortable. <S> Ignore theoretical calculators, because there is no ISO standard for frame measurements. <S> I would also caution that drop bars are not for everyone. <S> The bar type is a bigger commitment, because it is not straightforward to switch from drop bar gears and brakes to straight bar gears and brakes.
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As you found out, a huge part of cycling mechanics is the saddle height, and once you have got that right, you will find that there is plenty of alternative stem heights available to get your back at the angle you feel comfortable at. You have to rely to a large extent on bicycle shop staff advising you, taking to account what kind of riding you want to do as well as your height and relative proportions. If this is your first drop bar bike you probably don't want a very aggressive position. I'd say back no more than 45 degrees from vertical and angle between torso and arms about 90 degrees when on the hoods where you will spend most of your riding time.
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Windproof jacket for winter riding where I live winters usually are -15°C to 5°C. For MTB I wear sports base layer and fleece jacket, but problem is wind goes right through making stomach and chest area very red and painful. I have a cheap windproof jacket, but it's unbreathing and sweat condensates on the inside, so stopping even for a short time in those temperatures while wet is dangerous for health. Wearing base layer + fleece + backpack i don't feel cold at all. All I need is something windproof in the front and still very breathable. Would cycling gilet/vest/waistcoat be sufficient? Are their fabric windproof? Maybe long sleeve windproof jacket is better, but are they breathable? Or maybe loose fleece at all and go with something else like softshell jacket? Please share your experience. <Q> Wearing a wind-permeable fleece on a bicycle in cold weather is less than optimum because cycling always involves wind (although you are moving relative to the air, rather than the wind moving relative to you. <S> Try a thinner insulating layer, and open zips etc to get some ventilation when working hard and avoid over-heating. <A> We are very fortunate that over the last 10 years there has been a lot of progress with technical fabrics, and now as riders we have a massive range of clothing to choose from. <S> Windproof materials come in a massive variety from very thin single layers of densely woven fabric to complex 3 layer fabrics containing a membrane, and often with water repellent treatments (DWR) sprayed on the outer facing layer. <S> Many manufacturers make use of the Gore Windstopper fabric, however there are some excellent lesser known fabrics too. <S> The exact solution chosen is very much individual preference. <S> Some riders run hot, others run cooler. <S> Some like flexibility with layers and don't mind to faff a bit, whilst others prefer a solution is easy. <S> You need to find the combination of windproofing and insulation that works for you, whether that is a fleece + light gilet, a fleece lined softshell, or multiple base layers under a thinner shell. <S> For me, when riding the mountain bike in freezing conditions, I like a long sleeve merino base layer, a jacket with windproof front panel and fleece back. <S> I then carry a thin waterproof shell and a primaloft padded gilet in my backpack in case <S> I need extra insulation or rain protection. <A> Another option is to block the wind inside the fleece. <S> It does reduce the insulation of the fleece, but not by much. <S> I'm not saying you need to go to the lengths of cyclists in the old days putting newspaper up their jerseys, but any windproof layer would do it. <S> In the past I've seen some (not specifically cycling) fleece gilets with soft shell or showerproof front panels. <S> They'd be ideal. <S> Even a tightly woven fabric helps a lot ( <S> down to about 0°C <S> I'm OK with a short sleeve jersey under a long sleeve except for sustained descents).
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When you add a wind-proof layer to your fleece you are probably over-insulated and get sweaty when riding, then cold when stopped. Specific product recommendations are off topic on this site as they tend to become obsolete quickly. There are plenty of breathable windproof, cycling specific jackets available and reviews are easy to look up.
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Cons of using an infrequent use long range e-bike battery trailer using SLAs So I've recently purchased an ebike and started thinking about how I could go long distances without charging. It occurred to me that whilst sealed lead acid batteries can't go through many cycles, for the odd long distance (~100 miles) some deep cycle ones could be perfect, especially if mounted within a trailer. I have a 48v e-bike, so I'd need 4 SLAs in series. I'd probably only use this a few times a year so other than the discharge from using them they'ed always be topped off with charge. Can anyone see any potential disadvantages of doing this? Perhaps SLA's are just too heavy and I wouldn't get the range I want? <Q> Lead acid batteries are heavy. <S> Too much extra mass, even in a trailer could to put strain on the motor and brakes. <S> Also, is it possible to run an eBike from an external DC power source? <A> A typical 12V, 12Ah SLA weighs about 3.5kg each. <S> Four of them would weigh 14kg. <S> Thats a lot of weight to haul around. <S> Add the weight of the trailer, say 7kg, that's 21kg. <S> How are planning connecting them to the bike? <S> I believe you can connect your 4 in-series SLAs in parallel with your Li-ion, but they're some caveats. <S> Damage to Li-ion is probable. <S> Connecting 4 SLAs in parallel is problematic as even identical model batteries have different characteristics. <S> I think the better and safer method would be to switch to the SLAs when the Li-ion has discharged. <A> More downsides to carting a lot of batteries about 1) <S> Recharging them. <S> You'll need a 12V car charger which will take from 4 hours to overnight to do one battery. <S> I've used a 3 way adapter to rewire three SLAs into one parallel 12V battery instead of the 36V serial battery needed to ride, and a smaller car charger took over 24 hours to charge them all at once. <S> You won't be able to use the bike's Lithium charger to charge the SLA batteries, because the chemistry is wrong. <S> So it means packing along two chargers if you intend doing an out-and-back overnight trip. <S> 2) <S> SLA batteries are reasonably robust now, but many still contain liquid acid. <S> "technically speaking" you should have a diamond-shaped hazardous cargo sign displayed. <S> There is a risk of cracking, or I managed to wear partially through the plastic casing on one battery, <S> so there's always a risk of an acid spill/release. <S> 3) <S> Wiring - your ebike will expect to receive 48V DC at roughly 6-7 Amps current into the system, assuming a 300W motor. <S> Remember thin wires means loss, so you'll expect something at least as thick as cheaper jumpstart leads. <S> It will have to follow the bike's draw-bar for support, but still have enough flex to turn corners. <S> Likely you want to disconnect the trailer at some point for charging, so a plug in the line will be good too. <S> Perhaps you're approaching the ebike the wrong way. <S> The electric motor is an assistant to your inputs, and its not the other way around. <S> For your long rides, you aim to use the assist judiciously and only when its needed like climbs, not all the time. <S> Should the battery run flat, <S> well you still have your legs. <S> Downside is your flat ebike is now just a really heavy normal bike.
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The SLA batteries on the back will have to have a strong but thick power cable to get to the battery fitment. You will need to monitor the voltage of your Li-ion and SLAs to prevent it from dropping too low, especially the Li-ion. You'd have to figure out what the mass of batteries you would need, and see if it would exceed the bike's maximum load specification.
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Clicking sound on each rotation of the pedals only when riding Let me prefix this by saying that I don't know much about bikes. Especially from the terminology perspective. When riding, I can hear a relatively quiet click when I push down on the pedals. It happens when either of the pedals are in the upwards position, even when I try to put on continuous pressure during the whole rotation. I also feel a slight vibration when it clicks. It seems to me that the sound is coming either from the pedals or from the part where they're attached but since I can't reproduce the issue when I turn the bike upside down, I can't pinpoint the source. This started happening a couple of weeks ago. In the mean time I took the bike in for regular maintenance and it seemed to fix the issue but it came back the next day, or the day after. What can I do to diagnose this issue? Should I just take it back to the repair shop, or is this something I can fix myself? The bike is Ghost Kato 2.9 if that matters. <Q> While everyone here suggesting the bottom bracket is the likely culprit (and they're probably right), I wanted to comment nonetheless and point out that this could easily be the less common issue of worn bearings in one of the pedals. <S> Try rotating the pedals with your hand. <S> If they don't spin smoothly, that's a good indication that you've got a bad bearing. <S> You can try taking the pedal apart and repacking the bearings/grease, but odds are the track is pitted. <S> The pedal will continue to fail. <S> They're cheap. <A> If the noise/vibration occurs on the downwards stroke of each pedal, then the problem is very likely in the bottom bracket. <S> You bike has a square taper crank with a cartridge bottom bracket. <S> That might be loose. <S> You can check for this easily by holding the crank arms and trying to wobble the axle. <S> There should be no movement or play. <S> If you can get the bike fixed under warrantee you should do that. <S> It helps to be able to point out a specific problem that needs to be fixed though. <A> I have a feeling that this could be an issue with the bottom bracket - often I find that if it has been installed without enough assembly grease (i.e. copper grease on a threaded bottom bracket), then it will click under load. <S> Another possibility is that, under load, a part is making contact with another part (e.g. the front derailleur may be striking the chain - try it in a different gear and see if it makes a difference, or even your foot hitting the end of a gear cable). <S> If I can't isolate the click I tend to take the whole crank and bottom bracket apart, clean, inspect and reassemble with as much grease as I dare - but if you don't have those skills I would probably live with the click rather than pay a bike shop to rebuild the bottom end of the bike - these are the kind of noises that can take a long time to solve! <A> It could really be anything. <S> Loose pedals (unlikely), loose cranks (i put my money here), loose chainrings, bottom bracket issues. <S> It could be a lot of things and it doesn't sound like you know how to take it apart <S> so I think the answer here is to take it to the shop. <S> Especially on a new bike, I highly doubt you've worn out your BB bearings. <S> But the BB itself could be coming loose. <S> But my gut says loose cranks for some reason. <A> And the clicking might not even be coming from the pedals, crankset, or bottom bracket. <S> I had the same issue of clicking when I pedaled, getting clicks on the downstroke on one side. <S> I never could find the problem - even going as far as removing the pedals, crankset, and bottom bracket and checking everything, only to find nothing wrong. <S> The clicking continued. <S> Then, about six months ago, my front wheel - an old Neuvation R28 with a lot of miles on it that I used as a training wheel - suddenly went significantly out-of-true. <S> A quick look showed that one of the spoke nipples had pulled right through the rim. <S> The rim around the spoke hole had cracked. <S> The wheel was probably close to 10 years old, and had literally tens of thousands of miles on it as it was the front wheel I normally used. <S> I changed the wheel, and the clicking was gone. <S> And it's never returned. <S> What I think was happening was the pressure of pedaling was putting just enough side pressure on the front wheel to cause the cracked rim to make a clicking noise. <S> It drove me crazy for quite a few months. <A> I had a similar problem a few weeks ago, although only on the left pedal. <S> Both of them were brand new, as was the bike. <S> Pedals were well tighten on the crank arms. <S> The solution was pretty simple, and actually documented in the notice. <S> I did not put grease on the pedal thread as instructed. <S> The clicking occurred after 5 or 6 weeks of riding (500-600 km). <S> Greasing the pedal thread was enough to get rid of the sound. <S> It is a very simple thing to do, I would try it before performing further investigation. <A> I had a loose spoke on the rear wheel that cause or seemed to cause the drive train to creak on every pedal going up hill or under load. <S> Easy fix. <A> I have the habit of breaking the ball bearings within my pedals. <S> On the regular (yearly) check by the local bike shop I would buy new pedals, have them installed and be without the click for a few months. <S> You can test whether it is this by putting no power on the pedal you want to test but still have it go round. <S> If the ball bearing is broken it will click louder under power. <S> If it is the ball <S> bearing(s) <S> in the pedal, the repair is quite simple. <S> Just a couple of new pedals.
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Final possibility is that a part is worn or damaged but needs to be under load for it to make a noise (pedal bearings/bottom bracket bearings/crank arms). Unless it's a clipless or expensive pedal, just buy another pair. If it is something that has gone loose, it's going to keep getting looser and looser until it falls off. I will say though, I've never had a bottom bracket go bad on me, and I ride thousands of miles each season, and beat the crap out of my cranks on rocks.
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Can a Shimano XT (mountain) hydraulic disc brake caliper be used with an Ultegra STI road brake lever? Specifically, is the XT BR-M8020 mountain caliper compatible with an Ultegra hydraulic road brifter like like the ST-R8020 or ST-R8070? I have confirmed that they both use BH90 brake hose ("high power" rigidity). If I just ensure to use the right fittings for both sides of the hose (the banjo bolt from the SM-BH90-SBLS hose kit, and the straight brifter connectors from the SM-BH90-JK-SSR hose kit) can I be confident this is safe? I'd heard that recent Shimano road and mountain hydraulics of the same hose (BH90 vs BH59) were mostly cross-compatible, but I just read that even inside the upcoming XTR M91xx series of mountain brakes (which both use BH90 cable), Shimano recommends a totally different mountain brake levers for the 2-piston XTR brake (the M9100) vs the XTR 4-piston model (the M9120). Why would you need a different brake lever for these different calipers with the same size hose? How could you know which post-mount caliper (the M9100 vs M9120) would work with an STI ST-R8020 brifter? (As background, I'm looking for a good, strong post-mount hydraulic disc brake for the front of a tandem with drop bars. I will be upgrading the Shimano STI brake lever / shifter at the same time I add the hydraulic brake.) <Q> Shimano recommends a totally different mountain brake levers for the 2-piston XTR brake (the M9100) vs the XTR 4-piston model (the M9120). <S> Why would you need a different brake lever for these different calipers with the same size hose? <S> The key is that there are two brake options available: "race" and "trail". <S> "Race" features 2-pot calipers and lever without Servo Wave™, which yields different modulation curve (more linear?). <S> The "trail" version is 4-pot and with Servo Wave™ levers, which has more of an on-off modulation. <S> very close displacement/pressure values to be deemed compatible. <S> On one hand, I did not hear about incompatibilities between any pre-9100 parts, and on the the other there's a lot of reports of mix-matching working with great success. <S> Unless there are reports stating otherwise, I'd bet on compatibility trend. <S> In the end, calipers are not that expensive to experiment with and there are cheaper options (BR-M520, BR-M640). <S> How could you know which post-mount caliper (the M9100 vs M9120) would work with an STI ST-R8020 brifter? <S> What Shimano "recommends" and what actually works are not necessary same things. <S> Shimano is a conservative company bound by legal responsibilities. <S> If you want 4-piston calipers to pair with STIs, take a look at Hope RX-4 SH (explicitly compatible, I run these) or Shimano calipers mentioned above. <S> As with all things new, there's not much feedback <S> , you might as well get that caliper and report results here as an answer. <A> I use Ultegra R8070 road shifters with Zee calipers and 180mm XT discs. <S> It is a joy to use, modulation and power are excellent. <S> Regarding the lever sensation, I don't feel any difference with a complete ultegra hydraulic brake set. <S> Firm feeling, not spongy at all. <A> I have XTR M9100 brakes. <S> Recently I have replaced the front caliper with a <S> XTR M9120 4-pot caliper with excellent results. <S> The rest is absolutely the same, hose, levers, etc. <S> Only the front caliper changed.
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As far as I know, all Shimano calipers/levers have
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Go tubeless with used tires I have some tubeless ready wheels and tires, but they were delivered mounted with tubes the old fashion way. I’ve been riding like that for more than 800km, and I wonder if there is a problem removing the tube and add some sealant after so long. Especially since I had a puncture from a small nail, meaning the rubber from the tire already suffered a small punch. <Q> Riding with tubes doesn't necessarily affect the tires ability to hold air without one. <S> In fact, I find it easier to inflate tubeless set-ups where the tire has already seen some use, as the carcass gets a bit more flexible. <S> That being said, any and all holes in the tire need to be sealed. <S> You may have caused some small ones all around the surface of the tire, but those should easily be handled by the sealant. <S> Depending on the exact size if the nail-induced hole you mention, sealant just might take care of that too. <S> If not, it can still be repaired with a dab of superglue, preferably applied to the inside of the tire. <S> If you happen to have suitable glue easily available, I totally recommend using it before adding sealant, as it has a tendency to make things messier and glue less likely to stick well. <A> There shouldn't be any reason the mileage would stop you from mounting the tires tubeless. <S> Tubeless tires can be unmounted and remounted with fresh sealant. <S> The puncture from the nail is another matter. <S> You'll need to patch the hole if this is the case. <A> Carefully inspect the bread if the tyre. <S> A tube less the is held in place because the tensile material in the bead is kept taut by the rim. <S> In other words, the bead cannot be lifted radially off the rim as its circumference is only marginally larger than the circumference of its seat on the rim. <S> Damage to the bead, eg caused by tyre levers, may compromise the tyres seat. <S> This might be immediate damage like abrasions or cuts. <S> Or less obvious damage like over straining the bead by to much stress. <S> In particular for road tyres at comparably high pressures and typical use scenarios this may be a cause of concern. <S> For example, a tyre blowout at during a fast descent (eg 15m/s) may be somewhat inconvenient. <S> As an aside: There is a controversy if high pressure by itself is a concern. <S> Allegedly Conti does not offer road tubeless for similar reasons (no reliable sources). <S> On the other hand are countless posts of cyclists running tubeless at high pressures. <S> And of course several tyre manufacturers offer high pressure tubeless tyres (eg Schwalbe, Hutchinson) – a statement by itself. <S> Schwalbe published also compatibility charts .
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If the hole is large enough that the sealant cannot seal it initially (or can't seal it at all), you may have trouble getting the tire inflated to the required pressure to properly seat the bead. Jan Heine (Compass tyres) recommends not to use tubeless tyres above 414 kPa (60 psi, 4 bar) at all (cf Heine's blog ).
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Big dent on frame: How did this damage happen? I just bought this second hand Ridgeback Impulse folding bike for my partner. I'm a wheelchair user and it was dark and rainy when I collected the bike. So... I didn't check it (facepalm) I just got the seller to put it in the boot for me. It's been in the boot for 3 days, folded, and as far as I am aware, nothing has happened to it while it's been there. Took it to the bike shop (and nothing happened on the way there either), and we notice a big old dent on the frame, in a bad place, which means the bike is unsafe. Seller thinks I did it, I think she just didn't notice it. She has no photos on the affected side. It's pretty hard to spot unless you're in the lighting conditions that we were in when those photos were taken. It also looks almost like it's meant to be there - until you realise there's no reason, there's also a crease down the middle of it. My question for you guys is... in your experience - how would a dent like this happen? Could it happen from a folded bike in the back seat going over a road hump? etc? What force would be needed to make a dent like this? It's pretty big - and would have been inside the fold if it happened in the car. Just don't see how it could have happened, while the bike was folded, in a car. But at the same time, if it has been me, I don't want to screw over the seller either. Help!! Thank you <Q> Here is a photo of a similar bike. <S> While image is of low quality, the dent is visible: <S> However, as pointed out by Lamar Latrell in comments, in your second photo the weld to the headtube has a dark spot in it. <S> I cannot tell from the photo, but you or your bike mechanic should check if it is a damage in the weld seam, or just damaged paint. <A> However, it's in the realm of impossible-ish for a dent that severe to happen without paint damage or a clear mark in the paint from whatever did it. <S> It sure looks like it's there intentionally to buy clearance for the steering mast when folded. <S> If folding the bike up corroborates this, there's your answer. <S> If it did somehow happen via the mast or another part of the bike getting smushed into it, that would have taken a huge amount of force <S> and then it would be an unlikely coincidence on top of that for there to be no paint damage or damage to the mast or wherever else. <S> So that's probably not what happened. <A> I think you'll find that the handlebar 'stem' folds to the left, and will line up with the dent when folded. <S> If the dent is not supposed to be there, my best guess is that the handlebar was folded then, pressed into the frame, perhaps be the wheel and fork being forcibly turned to the left. <S> The dent just does not look like it's accidental. <S> There are no paint cracks and the seat stem presumably is not damaged. <S> Any force that could dent the frame like that surely must have damaged something else too. <A> I have the same (model) bike and it has the same 'dent'. <S> If you undo the front lock (to fold the stem / handlebars etc down), the stem fits / lines up perfectly into the 'dent'. <S> I have no doubt that this is a design specification / feature. <S> My bike (cost me £40, about eight years ago), it's an excellent bike.
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It seems that this dent belongs in the bike. If it is damage then no one here can say for sure how it happened.
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How different it is to ride with same gear ratio with 26" and 28" Do you know how much of a difference it is to ride with specific gear ratio (example 48/16) with 28" wheels and 26" wheels? <Q> Yes. <S> You can do the math on this: (chainring ÷ sprocket) <S> × wheel size. <S> With a wheel that has an outer diameter at the tire of 26", you'd get 78 gear inches. <S> With a 28" wheel, it would be 84 gear inches, or about 7% higher. <S> On a multi-gear setup, I've found that a 7% step is just about the smallest step that's really noticeable. <A> A larger wheel (including the tire) just gives a higher effective gear ratio.vBicycle gear ratios are often specified in gear inches , which takes the diameter of the driving wheel into account. <S> Gear inches = diameter drive wheel (in inches) <S> × size front sprocket / size rear sprocket <S> [Source: https://www.sheldonbrown.com/gain.html] . <S> Use of inches is traditional, you could of course use metric units. <S> Obviously, you can calculate the sprocket ratios which give comparable gear inch values for each wheel size. <S> Assuming wheel with tires have an actual diameter of 28" and 26", a 28" wheel gives 28/26 = 1.07 i.e. 7% higher gear ratio over a 26" wheel. <S> Choosing 26 and 28" wheel diameters for comparison is a little strange. <S> A 559mm rim MTB wheel with a 2" tire would be about 26" in diameter. <S> A 622mm MTB wheel with a 2.25" tire would be about 29". <S> Assuming you would use similar tire sizes on each size wheel, you can simply divide rim diameters. <S> 622 <S> mm <S> / 559mm = 1.11, i.e. the larger wheel gives about a 11% higher effective gear ratio. <A> A 26" wheel ridden at 26 km/h will give you exactly the same cadence as a 28" wheel ridden at 28 km/h. <S> And vice versa. <S> It's really as simple as that.
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So, a gear that's optimal for riding 26 km/h on a 26" wheel will be optimal for 28 km/h on a 28" wheel. Also, you can directly calculate the difference in effective gearing by simply dividing one wheel diameter by another.
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Is there any reason for the rear frame and bottom bracket to be asymmetric? I just received a new non-brand carbon frame and immediately noticed that the bottom bracket looks to stick out significantly more to one side than the other, and the rear bottom forks also seem to be have slightly different dimensions - both somewhat asymmetric along the center line of the frame. Is there any reason for a frame to be designed like this? Does it have something to do with it being a disc brake compatible frame? Or is this more likely a manufacturing / design problem? Here are some images: Thanks! I really appreciate any help + advice. <Q> The non drive side bottom bracket shell and chainstay are just more built up. <S> On reason is providing clearance for the chainrings on the drive side. <A> Many bikes need to get creative with the path that the drive-side chainstay travels along the Y axis, in order to "thread the needle" between the rear tire and the chainrings, which can be a very tight fit. <S> It's fairly common for the drive-side chainstay to be stouter, because that's what is most directly loaded when you're pedaling. <S> Cannondale even uses asymmetric bottom brackets. <A> Is there any reason for the rear frame and bottom bracket to be asymmetric? <S> Given that there are different asymmetric forces on the parts of the frame because of that, there's plenty of reason for a frame to be asymmetric. <A> Or is this more likely a manufacturing / design problem? <S> Absolutely not. <S> Carbon frames are made using moulds and jigs so every frame that a factory produces should be exactly the same shape, except for tiny variations caused by hand-finishing. <S> This recent GCN video shows the processes involved in making carbon frames, though be aware that it promotes <S> Look bicycles quite heavily: <S> How are Carbon Fibre Bikes Made? <S> | LOOK Cycle Factory Tour . <S> Asking if it's a design problem presupposes that it's a problem at all, and the other answers explain why it's not. <S> And bear in mind that a manufacturer who released a product with something so obviously "wrong" about it would have had to make an enormous series of huge mistakes. <A> A good question for the manufacturer! <S> My guess is that it's to reduce flexion losses in the frame due to the force you exert on the pedals and chain. <S> Putting them more in line and giving your forces less of a lever arm would reduce those losses, making the bike more responsive and faster with the same effort. <S> There's a lot written about frame design, reducing flexion, etc.
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Some bikes have a drive-side chainstay with a downward kink to minimize chain slap. The crankset, chain, and gearing are all on one side, making just about every standard bicycle asymmetric. The bottom bracket shell does not really stick out more on the drive side, it's symmetrical around the center line of the frame.
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How to recognize a tubeless tire? I suspect that the used bike I want to buy might have a tubeless tires, but one is flat. Is there any external feature to look at that would allow easily to tell this for sure? I have no experience with tubeless tires and would not know how to replace it. <Q> While your question of identifying a tubeless tyre has been answered, I think that might not actually be what you have to worry about. <S> A bike might come with tubeless tyres, but that doesn't mean that they're set up tubeless. <S> The tyres might still have a tube in them, so your concern should be identifying whether there's a tube inside or not. <S> The easiest way to do that is to look at the valve stem, because a tubeless valve will almost always be secured with a substantial lockring, whereas a tube with a presta valve might have a little silver lockring or usually nothing at all. <S> Any wheel with a Schrader valve is almost certain to have a tube in it as tubeless Schrader setups are extremely rare. <S> This isn't foolproof, because some people will put a big lockring on a tube and some might put a small one on a tubeless valve, but I'm confident that this will be accurate over 95% of the time. <S> Schrader valve: Presta valve (tube): Tubeless presta valve: <A> Look at the tire sidewall for model/name, tubeless tires usually have TL, UST, TR or Tubeless in it; some tires don't (like Schwalbe Pro One), so google the model and see if it's tubeless or not. <S> Keep in mind that some MTB tires can be setup tubeless regardless of what manufacturer claims, in this case you can unseat some tire bead and check if there's tube or sealant residue inside. <A> For a tubeless setup you need three things: the right rim, the right tire, the right valve-stem. <S> Carbon side up shows how to identify the valve stem, and the tire and rim should be marked, but you need to check all three, because having tires and rims rated for tubeless may be used with a tube (I do this all the time on riding lawn mowers because their rims suck and leak even though designed for tubeless operation.) <S> However in your case there is an easy check since there is a flat tire. <S> First look at the valve stem. <S> If it is a presta use your fingers to loosen the stem nut (skip if it is too tight to loosen by hand), then wiggle the tire relative to the rim while watching the valve stem.
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if wiggling the tire moves the valve stem you have a tube if you feel the tube stretching against the valve stem, you have a tube, otherwise either you have a tubeless setup or a burst tube.
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How much cycling distance is needed to travel every day for good muscular exercise? As a bicycler I used to travel on cycle daily for about half an hour to maintain fitness of my legs and body.But I want to know how much time and distance is needed for a good exercise. <Q> As individual speeds vary depending on fitness, bike and conditions, most information on this subject discusses intensity and time spend exercising, rather than distance. <S> Most leisure cyclists ride between 10-18mph (16-30kph) on the road, a bit less off-road. <S> As you can see it's a fairly wide range, so time and intensity are better measures. <S> They can also more easily be applied to other sports. <S> For good health, the WHO recommends : Adults aged 18–64 should do at least 150 minutes of moderate-intensity aerobic physical activity throughout the week or do at least 75 minutes of vigorous-intensity aerobic physical activity throughout the week. <S> If you'd like to improve your cycling fitness as well as your health, then British Cycling has a number of beginners training plans , depending on what you would like to achieve. <S> However, not everyone responds the same way to exercise, so the improvements are not guaranteed. <A> There is no real answer to this, as it totally depends on what you mean by 'good exercise'. <S> For a professional racing cyclist it means 30 hours a week of structured training including effort above an below that required for an actual race. <S> For adults the American Heart Association recommends as a minimum : <S> at least 150 minutes per week of moderate-intensity aerobic activity or 75 minutes per week of vigorous aerobic activity, or a combination of both, <S> Work up to a level that is sustainable and enjoyable for you. <A> My legs are pretty toned, and when I have to step up on the travelled distance it's not a big deal. <S> But a more precise answer strongly depends on the single individual. <A> The distance covered is only one measure of your trip. <S> The efforts and rewards of an exercise session will be related to both the length and the intensity. <S> Your 30 minutes could be 5 km at a casual dawdle, or 20 km at a hard pace. <S> Slower sustained riding builds the "slow twitch" fibres which can fire repeatedly for long times but aren't that strong. <S> These are "endurance" muscles and help you ride for a long time. <S> Short, High intensity efforts build the "fast twitch" fibres, which are the "sprint" muscles. <S> These get tired real quick and once that happens <S> you have to slow down. <S> Riders with high endurance can ride all day at a moderate pace. <S> Riders with fast twitch muscles can burst into fast sprints but may not have as much endurance. <S> Ideally you want both. <S> Relevance? <S> You need to mix it up - for example: From a red traffic light, go hard in a bigger gear than normal, right up to your fastest speed for as long as you can, then relax. <S> See if you can vary your route to get in a hill or slope to climb. <S> Move your position on the bike a little, to recruit and train other muscles - you'll feel this. <A> As a bicycler I used to travel on cycle daily for about half an hour to maintain fitness of my legs and body. <S> But I want to know how much time and distance is needed for a good exercise. <S> If your goal is to get strong muscles, I suspect half an hour of hard riding, riding on a hilly terrain, sprinting from stoplights, climbing hills standing is enough. <S> A 3-hour ride won't develop your muscles more than a half-hour ride would do, because the last hours you are anyway so tired that your average speed drops and <S> you aren't using the full strength of your muscles anymore. <S> If your goal is to reduce weight by burning fat, I would suggest to allocate much more than half an hour for your ride. <S> Start to ride to some direction. <S> When you start to feel exhausted and your average speed drops, start to ride back using the same route. <S> This way, half of your cycling time is done when you are exhausted. <S> This is important: fat releases energy slower than carbohydrates do. <S> To burn fat, you need to exhaust your supply of carbohydrates first. <S> The exhaustion occurs because your supply of carbohydrates stops and energy comes from burning fat. <S> If you carefully calibrate the length of your trip so that you will be back at the moment you start to feel exhausted, you won't lose much weight. <S> The important part is that you have to ride when feeling exhausted, to lose weight.
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How many km and at what level of effort you can ride depends on your current level of fitness. Depends on what your goal is. I have no hard data to answer this, just my experience: I commute every day, 13 km one way, practically flat, and I do my best to do the route in 30-35 minutes with a city bike.
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Can a bike have both Schrader and Presta tires? I have Kona Dew 2018 and the front tire has a Presta valve while the back tire has a Schrader valve. Is it common to see bikes have different valves for each tire? <Q> Short answer, it's not common at all and probably wasn't like that when the bike was new. <S> The valve that you need is determined by the rim rather than the bike. <S> If the rim is drilled out with a big enough hole for a schrader valve, then that's what you should use. <S> If a schrader valve doesn't fit through the valve hole, then you should use a tube with presta valve. <S> If one of the rims on the bike has been replaced (or drilled out), then they may no longer match and you would need one of each. <S> The more likely scenario is that at some point one of the tubes was replaced and instead of getting the correct schrader valve tube, a presta was used instead. <S> This is easy to check as the presta valve will not fit snugly in the valve hole. <S> If this is the case, it will work well enough in the short term, but I'd still recommend replacing it with the correct tube with a Schrader valve. <S> Over time, the rubber around the thinner presta valve will rub against the edges of the larger diameter valve hole in the rim and eventually wear out. <A> Why not? <S> The bike will roll anyway. <S> You would need two pump heads or an adapter to pump both tires, but other than that, it will work just fine. <A> There's no mechanical reason why you can't have one of each. <S> The disadvantages are purely practical. <S> You need a pump that can deal with both valve types, or two pumps, or to mess about with adaptors. <S> You need two kinds of spare tubes at home. <S> Most people who cycle longer distances bring a spare inner tube with them because it's much faster to replace the tube than to find and repair a puncture at the roadside (a second puncture on the same ride would need to be repaired). <S> You could just bring a spare presta tube which will certainly get you home if you replace your Schrader tube with it. <S> Whether any of this is a problem for you depends on your needs and preferences. <S> Presta valve stems are narrower than Schrader, so you could just replace the Schrader tube with presta and then you'll only have one kind of tube. <S> You could use an adaptor to avoid concerns about the narrow stem moving around in the wide hole. <S> In that case, you can replace your presta tube with the Schrader tube the rim was intended for. <S> If both your tubes match the rim they're installed in, you could replace the front wheel (cheaper than the back) with one that takes the same kind of valve as the back wheel. <S> Depending on what kind of bike you have, new wheels might not be all that expensive, though I'm not sure if I'd replace one just to get the convenience of matching valves. <A> My hybrid currently does, and it's not a problem. <S> I'm switching over to presta tubes so that the same spares fit that and my tourer. <S> That way I don't have to stock so many types of tube, especially in my commuting pannier. <S> The presta should be used with a spacer of some sort. <S> I prefer a rubber grommet as the plastic parts sometimes sold for the purpose have caused me problems in the past (hard edges abrading the tube).
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Check the rim of your presta wheel: it might just be that somebody put a presta tube in a Schrader rim.
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Pump head suitable for for small tires What is the best pump for small bike tires with narrow spokes? The pump head we have is large and is hard to place over the valve on our 20 inch tire. I've tried pump extenders but they are screw on and I always let out as much air as I put in when I unscrew them. I'm happy to get a pump that only works with Schraeder if this makes it easier to find one. <Q> It sounds like the issue that you're having is very similar to the one that time-triallists and triathletes have with disc wheels. <S> Luckily they've come up with a solution for exactly that. <S> What you're looking for is called a disc wheel valve adaptor, often referred to as a "crack pipe" for obvious reason due to its appearance. <S> The most widely used and durable one is the silca version ( https://silca.cc/products/disc-wheel-mini-chuck ) because of the replaceable seals and tiny head which is easy to fit in the tiny space with the valve. <S> There are plenty of options out there for less money as well such as this one by Fast Forward: http://www.wigglestatic.com/product-media/5360051984/ffwd-valve-adapter.jpg?w=430&h=430&a=7 <A> Found a good deal on ebay, this part should be perfect for this purpose. <S> 90 <S> Degree Motorcycle Car Tire Stem Extender Tyre Valve Extension Adaptor <S> They are not expensive - one I bought cost $0.99 USD. <S> The cap on the right-hand side comes off and reveals a Schrader connection. <S> These are also available in 135-degree and 60-degree angles. <A> Something like the Zefal 800 , which I link purely as an example of such a product, so show what they look like. <S> This style of pump is easily available and, as I recall, I bought one a few years ago for about £5.
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A pump with a hose that screws onto the valve sounds like it would do the trick.
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How can I cycle in winter while not being able to change work clothes? I started recently to bike to work, where we have a shower and I can change clothes. However recently I also started attending an evening course, where there is no place to change. So when I commute to work, it's easy. At home I wear my warm cycling clothes and then at work I switch to light comfort ones. However the problem happens when I want to go to the evening course. Since it's pretty warm at the classroom then I can't wear my warm cycling clothes and go to the course and stay with them for 2 hours. And since there is no place to change, then I can't change there to be able to return home from the course. Any ideas on how to solve this? or any clothing alternatives/ideas? My commute is pretty long. From the course to home is about 18KM. Edit: the temperature in winter here gets easily below 0, and the worst is -18 to -20. <Q> The main advantage is at the far end you can either wiggle them down while standing, or drop your pants in the toilet cubicle and shove them down around your ankles for comfort. <S> This works well with overshoes, in combination with a decent jacket and gloves. <S> I also wear a neck buff and/or helmet liner. <S> Try sitting nearer the window or door if you need a cooler breeze. <A> If you can't change in the toilets, you should complain about the disgusting state they're in. <S> In the mean time, it's possible to change while standing on your shoes, if you're careful. <S> However, I would say that 18km isn't a very long ride – presumably not much more than an hour, probably less (though I don't know how -20 affects this). <S> I don't find that I need padded shorts for anything less than around two hours, and I think you'd be fine without them, too. <A> Make sure you get a good set of mudguards fitted as these really do make a difference to whether you get covered in grime or not. <S> I've considered a cycling poncho for the wettest weather but have not bought one yet. <A> If you really need padded shorts (and I didn't for a 15 km commute, see the recent question on jeans in Amsterdam ) wear them under your normal clothes for the evening journey. <S> They aren't too warm in themselves, and you can get them designed to be underwear if you really want. <S> I have even worn padded tights under jeans for a whole day in work. <S> That was too warm even though the office was cool, but not much too warm. <S> For warmth, rely on overtrousers, that you can put on and take off without getting fully changed. <S> Merely waterproof ones keep the wind off but at those temperatures you might be better off with fleece-lined ones. <S> I assume you're in winter boots, so you might want to look into overtrousers that unzip a long way up to go on over boots. <S> Your top half is simpler, as most people will be adding layers before going out into that sort of weather. <A> Bathroom stalls. <S> Just learn to balance on one leg. <S> I've had success over the years finding shower/lockers in adjacent buildings if my employer's location was lacking. <S> 1/2 the time they're semi-public <S> so it's easy, sometimes I was able to convince building management to cut me some slack if they're familiar with my own building's shortcomings. <S> Also, don't rule out a local gym. <S> I have an annual membership at 24 hour fitness and use the gyms for changing and showers before/after rides to work. <S> You can even get around that 24-hour don't leave your stuff in the lockers <S> rule by simply moving your clothes from one locker to the next each morning. <S> There are no lockers, showers or changing rooms at work so the gym is my "facility". <S> Worth the $99/year... <S> yes, I got a sweet deal with 24Hour when they were on the ropes ~10 years ago. <A> I think in your situation, I would recommend breathable outerwear over wool (or other less smell producing) undergarments. <S> Finding a setup where you have an easily removable outer layer (that is conducive to cycling in your chosen temperatures) over an underlayer that is presentable (enough) for a class shouldn't be that hard. <S> Jackets/pull overs are easy enough and many companies make zip off style pants that can be easily removed. <S> I recommend aiming for presentable for public and letting fashionable go. <S> Likely the more difficult problem is usually smell. <S> Many performance sports garments will begin to smell after repeated use. <S> Wool has a serious advantage here, while some companies also make synthetic garments with chemical additions to reduce the problem (with varying levels of success). <S> Depending on how often your class is (I'd assume multiple times a week), washing garments every night might be impractical. <S> I used to get a week or so out of my wool underlayers while commuting before they got too stiff to continue comfortably in. <S> Perineum health is not to be trifled with. <A> Try to find a local gym nearby your evening courses and if it's cheap, you can take all of its advantages. <S> I mean shower and locker rooms. <S> The second advice is to find some windproof clothes that are easy to change. <S> I know there are some examples in the market. <S> I've even accepted a windproof jacket as a gift when bought a cooler. <S> Good luck, mate! <A> I used to change in bathroom stalls in these scenarios. <S> Sweat (because of no shower) can sometimes cause small issues, but generally speaking, this is a workable solution. <S> However, I might also suggest redesigning your cycling gear. <S> I commute all winter in a climate that gets plenty of snow and drops to -30. <S> The #1 thing that I have found here is layers. <S> I wear upwards of 7 thin layers, instead of fewer and thicker layers. <S> In your case, this would help you have options of the order of your layering, allowing you to selectively strip down to a comfortable level in the classroom. <S> Just be on the lookout for weird looks while you do it. <S> I still think I’d choose the bathroom stall.
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You might carry an extra pair of lightweight footwear to replace whatever is keeping your feet warm while riding. I've had success wearing legwarmers under trousers during winter. In that case, you can probably wear non-padded shorts "as underwear" and suitable layers, and you won't need anywhere private to change. I can also do some light workouts at the gym to break-up my AM/PM routine. Essentially, I bring a change of clothes for the day, leave my cycling stuff in the gym locker, shower...go to work, hit the gym to change back into my cycling gear and then head home. I would recommend multiple sets of cycling shorts (chamois shorts) so that they can be changed daily.
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Are carbon road bikes robust enough to use off-road? Regardless of the tire clearance, could I use my carbon road bike off road too? Can it handle the stress and load? Wont it break ? Does a road bike needs to be more robust to handle the offroad, gravel load? Thankfully Rob <Q> There are many CFC gravel, cyclocross and mountain bikes, so obviously CFC as a material can take the impacts. <S> If you ride a road bike on a harsh, bumpy paved surfaces it does not break. <S> If you want to be convinced of how tough CFC frames are, google for videos of the testing that manufactures put them through. <S> The primary features that make a gravel bike more suitable for bumpy and loose surfaces are stronger wheels, larger tires run at lower pressure, slacker steering geometry and longer chain-stays. <A> There are several answers to this question. <S> The one is fair use. <S> Like you wouldn't ride a roadbike on a severe downhill or in a cyclocross race. <S> Or have a 150kg rider on a lightweight racebike with flimsy, sparsely spoked wheels. <S> The other answer is given by the limitations imposed by the manufacturer of the bike and the components, mainly the wheels but also for some other essential parts like handlebars, stems and seatposts. <S> There are quite often limitations for rider weight and use of the bike. <S> Many of these are given by the limitations of the material but some are for reasons of legal liability and warranty. <S> The Trek owner's manual is a good example. <S> Link: <S> http://bike-manual.com/brands/trek/om/welcome/index.htm <S> You'd look under use conditions. <S> Still some things can't be avoided, like having an overlooked pothole, a harshly cobbled stretch of road or short bit over not yet properly resurfaced road repairs. <S> You may have to adapt your riding style, speed and behaviour to the conditions. <S> One last thing, a carbon frame or carbon rims don't exclude from using the bike on forest trails or other difficult terrain. <S> There are full carbon cyclocross bikes and mountain bikes. <S> On the harshest road race, the Paris-Roubaix and on the Belgian one day races in Flanders that cover long stretches of awful cobbles about all riders will go on carbon bikes. <A> See this video for a particularly nasty stress test of a carbon frame. <S> Specifically note that they replaced the shock with a simple metal tube. <S> It simulates a hard hit without any suspension (not even tires). <S> Generally, carbon seems to be pretty strong. <S> The reasons that it still has (had?) <S> a reputation to be more troublesome are these: It is strong in the directions intended by the maker. <S> That is, for stresses that occur during intended use, it is fine. <S> Anything else may not be - hence why you find a lot of discussions even about how to hang a carbon frame bike from a bike stand, or that you should not put it on top of a car. <S> Stresses that never occur during regular use can be neglected towards a more light frame during production. <S> This is, due to how the frames are built, not possible to the same extent, for aluminium or steel bikes, hence those tend to be less likely to be damaged by weird positions. <S> It fails catastrophically - i.e., it does not bend, or develop visible fissures over a long time, but when it fails, it fails with a snap. <S> This is, first, psychologically worse then a steel/alu bike bending, or having a visible omen a few rides before it happens; and also objectively a little bit worse - <S> a steel/alu frame can stomach a little dent in a noncritical section; a carbon bike can't. <S> It is easily damaged by screwing in screws with the wrong moment, or by using wrong lubrication. <S> This kind of damage is trivially avoided by using proper tools, but still a psychological factor. <S> So the question is not whether carbon road bikes are good for offroad use, but whether road bikes are good for offroad use. <S> And this depends solely on your riding technique. <S> Your body weight is several times the amount of bike weight, and can be an incredibly effective spring; what you do with it matters a lot more than the material of the frame. <A> While it's far from ideal for the task, I've done quite a lot of gravel riding on a road bike. <S> At the time, I was riding a rim-brake Scott Foil (2017 model) with carbon wheels. <S> I never found that the frame or componentry was at any risk of failing on me at any point. <S> You will probably get a number of small stone chips in the paint job, but that is just cosmetic rather than a structural concern. <S> The main issue that I had was the braking performance on loose surfaces was just awful. <S> I was running carbon rims, with 24mm tyres, so I needed to start braking long before any turns. <S> On one ride, I had a flat tyre while riding down a very steep gravel descent and was unable to come to a stop for several hundred meters because my rear tyre had even less traction once it went flat. <S> The issue of traction on narrow tyres is a major consideration that you will need to learn to handle through every corner. <S> You can swap out the handlebars for something wider and the stem for a shorter one, but road bikes are built to handle well at higher speeds and their geometry is designed around that.
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Speaking of handling, your road bike is likely to have narrower handlebars than an equivalent cyclocross or gravel bike, which will affect how well you can manoeuvre your bike on very rough terrain. The strength of a carbon fiber composite frame is not the problem.
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Putting a DH fork on an enduro bike: consequences? I am into downhill (DH) but I don't live 1) in a country with a lot of DH parks with lifting services etc 2) near such parks. Still I like riding rough stuff (in forests or in town) so that I would finally opt for an enduro bike. Concretely: I initially planned to buy a DH bike, the Commencal Supreme DH 29 signature 2019 and finally I will end up buying an enduro bike, the Commencal meta AM 29 Signature 2019 . But, I would like to replace the fork of the enduro bike with the one from the DH bike. Is this a good idea, as it would affect the geometry of the bike? How would this specifically affect the bike? Would it affect pedaling a lot so that at the end I wouldn't be able to use it for enduro (flat + uphill pedaling) as efficiently? What would be other effects? <Q> Let us assume that the wheel size stays the same at 29". <S> Let us also assume that a DH fork can be installed on that frame with no clearance or mounting issues. <S> What remains are questions of frame geometry and safety. <S> How would this specifically affect the bike? <S> I would say that the main parameter that changes is fork's axle to crown distance. <S> DH forks have more travel than enduro: let's say 200 mm against 170 mm that the bike you link to has. <S> So the top of the bike gets raised up for 30 mm. <S> Each 10 mm of change corresponds roughly to 0,5 <S> ° decrease of head tube angle. <S> So that makes it 1,5° or more. <S> It means the whole front end would raise up; if you stand on a perfectly horizontal surface, with a new fork it would feel as if you ride 1,5° uphill. <S> Needless to say such a change won't help you climbing up hills, but exactly the opposite. <S> 1,5 <S> ° is a lot of a change for head tube angle, which becomes 64°. <S> Most likely you will find it harder to make turns or to control your bike in turns. <S> Bottom bracket would be raised as well, possibly making the bike unstable in controlling, see this answer . <S> Less pedal strikes, however. <S> What would be other effects? <S> It would weigh more, and it would not be covered by vendor's guarantee any longer because using a longer travel fork certainly voids it. <S> Remember that an enduro bike frame and remaining components, such as handlebar and wheels, were designed, tested and certified for certain types of drop heights. <S> Is this a good idea? <S> No it is not. <A> The main problem that stands out to me is - as strong as Commencal's bikes are - when you slacken the head angle and add more weight to the front end, especially simultaneously, you are putting a ton of stress on your head tube which is likely designed around a specific travel fork. <S> As you could imagine there's already a ton of stress on the head tube as it is and <S> despite their bikes being build like tanks that's a lot more stress <S> so maybe if you ride delicately? <A>
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Downhill riding assumes harsher loads; you would not want your handlebar to snap. You can get a Rockshox Boxxer 29" DH fork in 180 mm length, that would do the trick.
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What should be my first upgrade? I've been planning to upgrade my Foxter Evans 3.0 (Low budget Bike) tolessen it's weight. What should I replace to lessen it? Also I'm a 5'11 personand my frame is a medium. Should I consider replacing the frame due to incompatibility of my height? I only have $400 budget. Below are the specs: 24 Speed Gears ! ( 8 x 3 Set Up) Epixon Fork -- new fork Shimano Gears Oversize Bar and Stem Heavy Duty Alloy Frame Square Tubing 27.5 Bike 5'4 to 5'10 Great Affordable Entry Level 27.5 BikeSpecifications: Frame: Foxter Alloy 6061 Thick Frame Square Tubing 27.5 Fork: Foxter Suspension with Lock Out Handlebar: Foxter Oversize Alloy Stem: Foxter oversize Alloy Shifter: Shimano 8 Speed Shimano Altus Brakes: Shimano Hydraulic Brakes Front Derailleur: Shimano Tourney Rear Derailleur: Shimano Tourney Crank: Foxter Steel Triple Chainwheel Cogs: Taiwan 8 Speed Tires: CST Jet 27.5 x 1.95 Seat Clamp: Quick Release Rotors: Shimano Rotor Discs Thank you for those who will answer. <Q> As everyone above points out, you'll pay double or triple to upgrade piecemeal. <S> Save up buy a whole bike. <S> Used if you have to. <S> The two items that I would consider are NOT on your list: If you are at the upper limit of your seat height, you might consider getting a longer seat post. <S> It's hard to pedal if you're not getting good leg extension. <S> (The frame is probably also too short for your torso+arms, but the legs matter more.) <S> Clipless pedals and shoes. <S> Your feet will thank you. <S> Plus, you can carry them forward to your next bike. <S> You can also upgrade tires once these wear out. <A> With an inexpensive bike like this upgrading individual components not worth it. <S> You can't really replace the frame - replacement frames <S> do not exist at this price level. <S> If the bike is too small for you, you need a new bike. <A> You say that your bike is incompatible with your height. <S> Upgrading won't fix that at all. <S> You also say that you want to save weight, but you're riding a low-end bike with suspension forks and big fat tyres. <S> If you're riding on the road or paved bike paths, you don't need either of those things. <S> By an overwhelming margin, your $400 would be best spent on a replacement bike; plus, selling your existing bike will give you a bit more to spend. <S> You should be able to get a nice second-hand bike for $400, or a decent new one. <S> If you do only ride on paved surfaces, consider a hybrid, which will give you a similar riding position to your mountain bike but will have narrower, lighter tyres and wheels, and probably a lighter frame. <S> (NarrowER, but not particularly narrow – we're not talking skinny race bike tyres, here.) <A> The best upgrade is yourself. <S> You could spend $500 making your bike 50g lighter with titanium skewers <S> or you could lose 5kg in a few weeks of hard riding. <S> You could try to make your wheels and derailleur go from 97% efficiency to 97.5% efficiency or you could increase your spin rate. <S> Etc.
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Either save for a whole new bike, or perhaps look at clothing and accessories that will make your riding more enjoyable and easier. You could upgrade to a higher front sprocket and new rear derailleur or you could increase your VO2.
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How durable are road or hybrid tyre tubes compared to mountain bike tyre tubes? The context here is that I'm using a mountain bike to commute and I'm considering buying a hybrid bicycle or road bicycle. I'm experiencing various issues that require repairs and maintenance. Perhaps the most time consuming being punctures. Even if the road or hybrid bicycle is faster, I'm afraid that this benefit will be negated by the time lost on more frequent repairs. I have no idea how these punctures/tears happen, I try to be careful with curbs and avoid any debris I can. How durable are hybrid bicycle tubes compared to mountain bike tubes? Another (and perhaps more correct) way of phrasing the question is to ask, what is faster for city commute where there is a lot of curbs, uneven surfaces, traffic, and similar challenges. A hybrid bicycle or a mountain bicycle, when factoring in the maintenance/repair time cost as well as the speed? As a bonus question, how much faster is a road/hybrid bicycle anyway? Are there any studies that look at average speeds in typical city commutes? Obviously they would need to look at the exact same route and be somewhat serious, not just being marketing blurbs. <Q> Having ridden both mountain and road bikes, I don't think tire/tubes designed for paved surfaces are actually any more puncture prone than tires designed for dirt or gravel, if used within their intended limits. <S> if you run your fingers over the inside surface you can sometimes feel embedded objects that are not visible. <A> You do not need to think about tubes' durability if you start thinking about tires' puncture resistance. <S> Most punctures (except snake "bites" caused by underinflation, i.e., user error) start with a foreign thing penetrating the tire. <S> Once a sharp thing penetrated the tire, it is only a matter of time when it breaks the tube. <S> There are simply tires with better puncture protection. <S> They exist regardless of riding style; that is, compatible both with MTB and/or road/hybrid tire sizes and widths. <S> Look for tires designated for touring or commuting, not racing. <S> The former are heavier but provide better puncture protection. <S> Alternatively, there exist kevlar bands that are placed between a tire and a tube and are meant to stop sharp things that penetrated the tire to go further. <S> If you are so determined on tubes choice, look for ones that come with self-healing sealant. <S> As a bonus question, how much faster is a road/hybrid bicycle anyway? <S> Any bicycle is as fast as a biker that drives it, regardless of bike type. <S> Especially when you consider commuting, not racing/competition. <S> Your choice of route, amount of traffic light stops, presence of narrow passages with a lot of walking people affect your commute more than bike choice. <S> There is definitely no such thing as "an average commute": some people ride 2 km in a straight asphalt line, others 20 km muddy gravel roads, third navigate in tight car traffic. <S> I my life course <S> I commuted on different bikes distances varying from 2 to 20 km, on surfaces varying from dry fresh empty tarmac to iced snowy car nightmare hell. <S> Any study attempted on the topic as you formulated it simply would not be of use for you personally, unless it was you who did it for yourself. <A> I recently rode my old commute on my MTB. <S> It took 40 minutes without traffic. <S> On the hybrid 40 minutes was a good run, but in rush hour, and I'm fitter now. <S> That implies the hybrid is quite a bit quicker, and it certainly feels nicer to ride. <S> My tourer (i.e. a slow, heavy road bike) is considerably quicker than my hybrid on the open road, but not measurably so in urban riding. <S> So overall a hybrid works well for commuting. <S> As for tyres, on a bike that's used for commuting and the odd leisure ride, just fit marathon plus or marathon supreme in about 32-35mm, pump them up every couple of weeks, and don't worry. <S> I carry the means to deal with a puncture, but I've had one or two punctures this year (10000km), and they weren't commuting. <S> There are other effective anti puncture tyres, but those are the ones I'm familiar with. <S> They're meant for touring and commuting. <S> Both my old commute and my current one are tarmac with potholes and debris, I no longer have any gravel on my commute, but happily take the same tyres on it on other rides.
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If you are getting frequent holes and tears in your tubes but not your tires, and you are not getting pinch flats, inspect the inside surfaces of your tires carefully for debris or small sharp objects that may be buried in the tire surface. Also, speed is only one consideration, you may be more comfortable and happier on a hybrid with relatively wide tires and a riding position that allows better control than a slightly faster but more uncomfortable road bike. It's impossible to say how much faster you will be on different bike types on your commute.
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What is the torque needed for chainring bolts? I have a bike that is no longer in production, but it has a standard drivetrain (FSA). I had some shifting issues the past couple days, and to my surprise when I did a clean/inspect, three of the 5 chainring bolts had dropped out and the other two were finger loose. I salvaged some bolts from my donor bike. I needed a breaker attachment to my 5mm hex to get them off. There was no residual threadlock on the threads. Now I'm unsure how hard I should tighten them onto the first bike. Why would they have come loose in the first place? How hard should I tighten them to prevent this from happening again? Would a dab of threadlock be good insurance? <Q> A Shimano "General Operations" manual states the tightening torque for road chainwheels is 12-14 N-m. <S> For mountain bike chainwheels <S> it's upped to 14-16 N-m for large and middle ring and 16-17 N-m for the smallest ring of a triple. <S> The website: <S> http://si.shimano.com/#/ The manual number I'm referring to: <S> DM-GN0001-20-ENG.pdf Blue loctite or equivalent threadlocker is indicated here as well. <S> I can't accurately surmise the cause of the loose and lost bolts in this specific case. <S> However my experience with situations of loosening bolts or part failure due to "coming apart" in various mechanical settings often comes down to incorrect or incomplete tightening of the fastener (bolt, nut, etc). <S> Part of this process is rechecking and re-torqueing after a break-in period of normal use. <A> Park tool has a great reference <S> Here (all inch-pound)Chainring bolt- steel <S> Shimano 70-95 <S> Campagnolo® 84-120 Race Face&erg; 100 Truvativ® 107-124 Jury is out on thread lock on chain ring bolts. <S> A do not believe a light thread lock will hurt ( until you need to remove them), but also believe correctly tightened bolts should not need it. <S> The problem is the little two prong thing used to hold the nut is unlikely to allow a decent torque. <S> Better to give the threads a good clean and lightly grease the threads. <A> You need to still check them regularly to ensure that they have not come loose. <S> Cable ties are a good insurance policy to stop them dropping out.
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On my race BMX's I put cable ties through the chain ring bolts once they are correctly tightened as this prevents them falling out if they come loose.
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Can I use WD40 and generic bicycle oil to maintain my MTB drivetrain? For years I've been using WD40, a brass brush, a rag, and some generic bicycle chain oil. My chain has no visible damage, and I have no problems with it. This is for a somewhat cheap MTB that sees everyday use for commuting. What oil? I don't even know, and I don't believe it comes with any specifications. It is the absolutely cheapest I could find on eBay, it costs less than 1 USD including shipping, for 50 ml. Is there any problem with doing this? If so, what is the problem? It seems to work great for me, contrary to what seems to be popular belief and advice found in professional (or not so professional, I have no idea who actually knows what they're talking about) maintenance videos? The steps outlined e.g. here are incredibly elaborate, they involve among other things, using a modified pair of nailbrushes to sandwich the chain, just to make sure that it gets cleaned properly. It also stresses how important it is to degrease it first. It also mentioned how you must use hot soapy water to clean it. It also suggests using aerosol lube before applying the actual chain lubrication. It is mentioned how you should use grease, and is this the shot where he painstakingly applies it to each link of the chain, by hand? Finally, it says it is not essential (which means, it is a really good idea to do it, you just don't have to ) to dismantle your drivechain every time you want to clean it. I don't do any of these things, at all. I use a worn brush and just rather carelessly scrub a bit at it, removing obviously large chunks and lager pieces of debris. Then soak it in WD40, wipe it off with a rag, use copious amounts of the cheap oil and then off the excess again. I've never had any issues. This is also where it gets to way below zero, there is a lot of salt on the road, often a lot of rain. The bicycle is stored indoors most of the time. This MTB has some cheap Shimano parts, Shimano M190 31.8, Shimano M191 42-34-24 CG, Shimano CS-HG30-8 11-32, and the chain is a KMC Z72. Trying to improve my own knowledge about bicycles, particularly in care and maintenance, seems to quickly make me run into a wall of enthusiasts that are just on a completely different level. It is rather demotivating. If there is indeed something wrong with what I do, it would be nice to know exactly what the problem is, and what I can realistically do to improve it. Because, doing what is suggested in that video, I think, is completely unrealistic to almost everyone except enthusiasts. <Q> This is fine, as shown by the fact that you've been doing this for ages and not had any problems. <S> The only thing I'd suggest is that there's no need to use "copious amounts" of chain lube. <S> It doesn't take long at all to just apply a dot of lube to each link of the chain as thown in the video, then let it soak in for a couple of minutes and wipe off the excess. <S> Alternatively, hold the nozzle of the lube bottle against the chain at one end of the rollers and use the pedals to rotate the chain once round, while dispensing a thin stream of oil, then repeat for the other end of the rollers. <S> If your chain has a quick link or similar connector, you can use that to see when you've been round once. <S> Ultimately, though, since you're wiping off the excess, the only question is whether you prefer to use less lube or less of your precious time. <A> You might have a slightly shorter chain life, and slightly more chain drag than if you followed the recommended chain cleaning procedure and used a better lube. <S> FYI <S> if I remember correctly there is a GCN video where they show a quick chain cleaning method using WD40. <S> WD40 is lube in a solvent, so it works to remove old lube and contaminants <S> then evaporates so you don't have to wash it off. <S> You might consider a better chain lube. <S> It's more expensive but if you apply a drop per chain pin as in the video a bottle lasts a very long time. <A> I think you're doing good job. <S> I think you can save time by using a chain cleaner tool <S> , I find it satisfying to watch the chain becoming clean just by turning the crank by hand. <S> You can buy the solvent or just use soap water. <S> After degreasing, I also use WD-40, but it's WD-40 Chain Lubricant. <S> It's probably the same as other lubes. <S> The advantage with WD-40 is, again, I just turn the crank and spray. <S> Because of the fine spray, there's less drips on the floor. <S> I wouldn't worry about damaging the chain, it will worn out before anything. <S> I replace mine every 10,000 km (really stretching it here) <A> Your system is fine. <S> You can pay a bunch of money for Friction Facts and find out how many watts you're losing by not doing what the pro's' mechanics are. <S> (Ha.) <S> But that doesn't matter. <S> Any alternative should be chosen only if it makes your life easier. <S> I used to use Tri-flow because it lasted longer than WD-40, but it was similar. <S> However, when I moved and began riding in dustier conditions, this thin, wet lube attracted so much dirt that maintenance became a nightmare <S> and I was always full of black gunk. <S> I eventually switched to hot-waxing the chains and putting DIY wax (same batch, just dissolved in paint thinner) on as a touch-up. <S> I have a cheap ultrasonic cleaner for parts cleaning and it works well on chains too, so it's not much of a problem for me, and I stay a lot cleaner. <S> This is way more work than most people would want to do, but I don't have to deal with the gunk on me or the bikes, so it's a net gain for me. <S> Wax ain't great in wet environments, though, as it doesn't keep the rust at bay. <S> I'd go back to tri-flow if I were in the rain more. <S> If your system works for what you want, stick with it. <S> I'm also down on sprays because it's really easy to get them on disc brake rotors and pads. <S> Drips tend to go only one direction. <A> You are totally right! <S> There is no one perfect way to lube your bike. <S> Few days ago a cleaned the chain with gasoline and a soft metal brush (there's a cheap kit at Harbor Freight) <S> I use half plastic container of orange juice to hold the gas and the dripping dirt. <S> Once dried I lube with some synthetic oil left for my electric generator (10-30 Pennzoil) <S> I applied with cotton swab on each link up, down and sides. <S> Then clean the oil leftovers. <S> It works beautifully!!
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You're basically using WD40 as degreaser (it's a very thin oil that will dissolve away thicker oily gunk) and then using chain lube as chain lube. You keep your chain relatively clean and lightly lubed, and there's not much more that needs to be done.
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Is there such a thing as 'eBike specific' freewheel? I've recently had the LBS replace the freewheel on my eBike after 500 ish miles of riding. The sprockets were not worn out, instead the freewheel bearing (not the hub bearing) had become loose. It looked like this was due to the bearing cup loosening on it's thread. My attempts to tighten it were futile, the LBS appeared unwilling to even attempt to do so, rather assuming that it was due to a low quality part. They also claimed that it might be because it was not an eBike specific freewheel. Does such a thing even exist? If it does, what about an eBike makes such a thing necessary? I challenged the LBS on that claim. They say the freewheel sees additional load. For a mid drive eBike that might make sense, but for a hub drive I don't see how that's possible. <Q> I agree with you that a hub drive e-bike should not impose any more stress on a freewheel than a conventional bike. <S> Whichever wheel you drive, the torque supplied by the motor is not going through the freewheel. <S> The torque transmitted by the freewheel is all generated by you, just as on a conventional bike. <S> A stretch would be to claim that you can generate lots of torque in short intervals, then let the motor drive you in between, while on a conventional bike you would have to be working all the time so the torque peaks would be lower. <A> Given that this question has failed to attract an answer, I will speculate a little. <S> The (probably) false reasons <S> The only text I could find online regarding Freewheels and eBikes is as follows: <S> Most of our rear hub motors have a threaded side cover which takes a standard screw-on freewheel gear cluster, rather than the more modern cassette freehub system. <S> While you can purchase freewheels from most bicycle stores, they are rarely available in more than 7 speeds and even then almost never with an 11 tooth small gear, which is essential to maintain a decent pedal cadence on fast ebike systems. <S> This implies that there is nothing mechanically special about freewheels sold for eBikes. <S> They do however have unusuall many speeds ( <S> whether or not that is wise is probably another question) and a large ish range. <S> The large range is useful because it means you can do without a front derailleur. <S> Mind you, none of the above is special to eBikes. <S> Road and mountain bikes also benefit from being able to go fast, and go up steep hills. <S> The (I think) real reason Freewheels with 8 or 9 speeds are essentially useless on most bikes since they tend to lead to bent and broken axles. <S> Therefore freewheels with more than 7 speeds are restricted to rear hubs with unusually robust axles. <S> The axles on my bike is about 12mm. <S> This is necessary to pass out the electrical connection through the hollow axle. <S> This means it is possible to mount a freewheel with more speeds with less risk of bending or breaking axles. <S> It's worth mentioning again that the above is more speculation than anything else. <A> My LBS doesn't like dealing with them because of the extra work getting the wheel on and off, dealing with the wiring etc. <S> The electrical connection is simple, but they're bike mechanics not electronic engineers and get all twitchy. <S> Another issue is that the axle is almost always 14mm and longer than usual, this can make it tricky to get the tool in to get the freewheel off. <S> This and the fact most ebike freewheels are the cheapest chineseium available make the job far much more like hard work than it should be. <S> The only solution I know is to get the freewheel off by any means (even the destructive ones), make sure everything is spotlessly clean, prep everything, select a freewheel of exceptional quality and care for it <S> like you never have before. <S> On a side note, if you're riding with the motor and not pedalling, don't leave your pedals/cranks in the same position every time - when the motor starts/stops, depending on how you set it up, it can "kick" a little, this is absorbed by the freewheel and you may find it beneficial to spread the stresses over all the bearings rather than the same one(s) every time.
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Rear hub motors for eBikes typically seem to have slightly larger diameter axles. I've handled a number of such ebike motors/hubs with screw on freewheel(s) and can confirm that every single one was a standard screw on freewheel.
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What are the dangers of the tyre/inner tube bursting? Is there a danger if the tyre or the inner tube suddenly burst? <Q> The main danger can be an immediate loss of control. <S> Depending on when/where is happen, that loss of control can be minimal if going at slow speed to kill you if it happens going downhill at high speed. <A> Indoors it's not good for your hearing. <S> I once misread the pressure ratings and exploded two tubes in a row. <S> At high speed it could cause you to crash, especially if it happens on the front wheel. <S> This is why it's always good to inspect the tyre for bulges if you feel a thump-thump-thump. <A> If a tyre or its tube bursts while cornering there's a strong chance of it losing grip. <S> On the straight it's less likely to be serious. <S> I've had a front blowout on the straight <S> and I wasn't close to coming off. <S> But I was going slowly to stop under the next light and investigate the dodgy noise (which turned to to have been the tube bulging through a slit in the sidewall and rubbing on the fork). <S> A rear blowout on the straight is probably the most common, and the safest form of blowout. <S> I've seen a few happen and they've never resulted in a crash. <A> Last time this happened around me I was wrenching on a bike and someone in the front of the shop blew out a tube. <S> It was so loud the tool I was holding slipped off and made a nice scratch in the frame. <S> So <S> yeah, <S> it’s dangerous.
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Losing grip on the front while cornering is quite likely to result in a crash, less so on the back, but if it's because the tyre is suddenly flat you may not be able to recover.
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How much can we change our bike wheel diameters before needing another bike fit? How much can we change our bike wheel diameters before needing another bike fit? If we change the size of our bike tires, it raises or lowers the front or rear of the bike. That means it can affect the reach, handlebar height, setback, saddle angle, and handlebar angle. That means even after tilting the seat up or down to make it flat, we need the setback readjusted, and we likely need a new stem to readjust the reach and handlebar height. Adjusting the setback affects the reach. It seems like even a mm of adjustment can be significant in terms of optimizing our bike fit. If we extend our knees, our hamstrings are engaged when extending our hips like on the downstroke but if our knees are bent, they don't get activated so we get less power. Most of us notice the stretch in our hamstrings when when trying to reach our toes with our knees extended. There's a reason why a bike fit can take at least 2 hours. Some bike fitters recommend another bike fit when we get new shoes as they can have different sole heights in addition to needing the cleats adjusted. Sometimes we need or want to change the diameters of the wheels. Examples include: Tire clearances are different for both the front and rear wheels while the rider desires fitting the widest tires possible. Adding a fender also decrease tire clearances. Even replacement tires with the same width markings can have slightly different actual widths when installed onto the rim. Rim replacement since changing the rim inner widths can affect the tire widths. Spare wheels since some cyclists have multiple wheels for different conditions, race days and training, different gear ratios, etc. Upgrading the hub to a hub dynamo, internal hub gearing, coaster brake, power meter, etc. The new hub may have different hole counts so a new rim, which may have a slightly different inner width may be needed. How much can we increase the difference in the two wheel diameters before we need another bike fit? <Q> The thing about bike fit is that it's almost exclusively about relating your body position to the mechanical parts of the bike. <S> The relationship between handlebar, saddle and pedals is unaffected by changing the wheels. <S> If you make a change to one wheel diameter it will be equivalent to the tiniest of slopes. <S> Let's take a worst case: <S> That's a 1% change. <S> Does your fit change on a 1% slope? <S> I doubt you can even measure whether the saddle is level to that precision <S> , for example, never mind whether it should be. <S> You'd have to change the bead seat diameter for it to make much difference, and while people do put 650B wheels on 700C frames they normally do both at once. <S> Shoes are very different, in that they come between your body and the bike, and in a particularly important way. <A> You would need a really big difference in effective front and rear tire diameter to create enough tilt in the frame to effect rider position. <S> Replacing one rim with a slightly wider or narrower one, or replacing a tire with one of nominally the same size will make no appreciable difference. <S> You would get the same level of effect by increasing the difference in tire pressure between the two wheels. <A> If I understand your question correctly, you are worried about your bike fit might change when you tilt your bike to the front or to the back. <S> I'd ask you another question - <S> do you change your bike fit when riding up the hill or down the hill? <S> Imagine <S> you are climbing a 7.5% hill (say it's Mount Ventoux). <S> This incline means that for every meter distance you climb 7.5 cm - on the average. <S> The axle distance is usually around 100 cm for the road bikes. <S> Which makes your bar 7.5 cm higher than usual. <S> Will you change your bike fit for the occasion of climbing and then again when you're about to descend? <S> If your standard tyre size is 700C-25 <S> and you happen to put 23 in the front and 28 in the back <S> , the front of the bike will be 5 mm lower than the rear of the bike. <S> You can compare this to a 0.5% descend . <S> Since you didn't change your bike fit for Mount Ventoux why would you do it for a mere 0.5% descend? <S> Even if you make 1 cm difference in tyres, it's still 1% decline. <S> Do you notice it while riding? <S> TL;DR; - the tyres that would cause the necessity for bike fit change are not available for purchase.
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Say you go from 35mm tyres to 25mm on the same rim (a 10mm difference in nominal radius, which is what actually matters) on a bike with an unusually short 1m wheelbase. More typical changes on more typical bikes would work out closer to 0.2%.
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Issue shifting from largest cog to second largest Got a Canyon Spectral 3 weeks ago, have done around 2 hours riding on it and have noticed an issue with shifting from the largest cog to second largest. The drivetrain is SRAM NX 1x12. There are two different scenarios: When the bike is upside down The chain will stay on the largest cog no matter how much I shift down, the derailleur does not move when these shifts are done (hence why it stays on the largest cog). If I give the derailleur a gentle push it will then move into gear as the slack is there for it. When it's in a different gear I can go all the way down to the smallest cog fine and back up to the largest. After reaching the largest it repeats the issue. When riding When in the largest cog and riding it will shift after around 5 seconds of pedaling on some occasions and almost immediately when cornering like the motion helps it out of the gear. When on the largest cog and clicking shift twice it will skip down into the third largest no problem. Video of scenario 1. https://www.dropbox.com/s/qs2k2ma9rgvlth4/VID_20181212_184618.mp4?dl=0 I'm already contacting bike shops and canyon have suggested taking it to a bike shop but putting this up to see if anyone has any ideas or has had a similar experience. <Q> I would honestly just take the cable off the and use your thumb to push the derailleur into the biggest gear while turning the peddles. <S> do this over and over again. <S> if it ever sticks then you know its your derailleur. <S> if it does not stick you can move on and look into cable issues..... <S> hope this helps. <A> I have a Sram Force1 1X11 with e*13 9-42 cassette. <S> It was clear that the issue is in the friction of the housing <S> so i can't do anything about it, so I played around with the derailer clearing set screw ( <S> idk how it's actually called) and that helped a little bit. <S> What did the trick in the end was shortening the chain two links so the whole system has some more tension on it! <S> So check if it's possible to shorten your chain a little bit. <S> My system shifts perfectly now! :) <A> Either the derailleur is sticking when at it's most inboard position, i.e. on the largest sprocket, or the shift cable is sticking in the housing somewhere. <S> It's not surprising that the derailleur will eventually shift up when on the trail <S> , it's being shaken and vibrated by trail irregularities which overcomes the stickiness. <S> Fiddling with the barrel adjuster will not do anything. <S> The cable is payed out from the shifter when changing to higher gears so it can't pull the derailleur outward. <S> The barrel only adjusts the length of cable and hence position of the derailleur not the cable tension in any case. <S> You want to figure where the stickiness is. <S> Detach the shift cable from the derailleur. <S> With the bike on a work stand or inverted, push the derailleur manually while pedaling to change gear (it really helps to have a friend pedal for you, and be really careful to keep your fingers out of the chain). <S> If the derailleur sticks in the lowest gear there's the problem. <S> You can also hold the shift cable with a pair of pliers, put some tension on it and work the shifter, you may be able to feel some resistance. <S> I've never encountered a malfunctioning new derailleur. <S> If the derailleur is sticking perhaps working it through it's range of motion a few times will free it up. <S> Look for dirt, dried lube or anything in the parallelogram that might be binding it up. <S> Old, dirty cable can develop excess resistance and stickiness, The solution is to replace them, but your's are obviously new. <S> Perhaps pull the cable out of the housing, give it a wipe down and add a little lube. <A> Can you put your bike in a stand and shift while turning the crankset forwards? <S> Eagle drivetrains never shift particularly well into or out of the biggest cog at the best of times. <S> Did you tune your shifting with the bike upside down on the floor like in the video? <S> Did you tune it to shift into the big cog by clicking the shifter while the pedals weren't turning, then turning them? <S> If so, you probably just need to reduce the cable tension a little. <A> Have seen this only once before. <S> It was the upper limit screw "marked L on the derailleur body" was too tight. <S> When you shift into the large ring the chain wedges into the ring and is held by the limit screw. <S> That is why shifting twice to a higher gear pops it loose. <S> It increases the derailleur spring tension and overcomes the "jam", Loosen the limit screw 1/2 turn. <S> Be sure you are not crosschaining ( <S> big ring front to big ring rear). <S> It compounds the "sticky shifting" issue. <A> I agree with w Cliff, check the hanger... <S> 1x12 NX is fragile, and temperamental. <S> Must be set precisely. <S> You may have done everything correctly, but have an untrue hanger... <S> in your 2 hours of rip roaring riding, did you strike your derailuer on any rock, root beds, or doorframeS? <S> I understand your frustration, sometimes you have it right... <S> but it can’t be ‘right’ , due to bad hanger. <S> Hope this helps <S> , I know <S> I’ve made that error myself. <S> I’m suprised to hear a sketchy problem with a Canyon. <S> Check it out, it could be that simple.
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I had the issue that I had to tug a little bit on my shift cable to get the derailer out of the biggest cog to the second one. I tried new cables, I shortened the cable housings as much as possible but it didn't help. While not the main issue that you're having, shifting while not pedalling will always make it worse.
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Why did my chain start coming off on the right side of the chainring sometimes when I am pedaling in high gear? I have a 7 speed bike with one chain ring. Recently the chain has started coming off the right side of the chainring occasionally when I am pedaling. My bike has about 2000 miles on it and is about 7 years old. I ride in the northeast in winter so it is exposed to road salt. I think the chain is coming off when I am in 7th gear and the chain is angling in to the chainring from the right side where the smallest sprocket (7th gear) on my rear wheel is. I suppose this angle is too steep so that the teeth on the chain ring do not fit into the spaces in the chain but hit the edge of the chain and the chain falls off. I checked the crank and I don't think it is loose. I can't reproduce the problem deliberately. I see on the internet some people change their chain at 2000 miles but some wait much longer. Could a worn chain cause the problem? Is there any other likely explanation? Why would this start to happen now? Is there any way to fix it? Thanks <Q> Chains life spans have huge differences, depending on both conditions and maintenance and quality of the chain itself. <S> If you have 2000 miles on the chain and it has been exposed to road salt, it is very likely that it has been worn out. <S> If you are lucky, you can fix it by just replacing the chain, but if the chain is badly worn you may have replace the cassette and at worst case the chainring too. <S> If you have to replace the chain ring, there are so-called narrow-wide chainrings that are designed to hold the chain better in single chainring setups. <A> Worn chain or chainring is a possible cause, but you should check derailleur tension as well. <S> If the derailleur A (on the cage) or B (at the mounting bolt) <S> pivot springs is weak or has failed there may not be sufficient chain tension when on the smallest sprocket, and this is allowing the chain to drop off the chainring. <A>
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Look for a bent tooth on the chain ring, this can throw a chain, especially when the chain is at an angle.
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Chainring and cassette configuration How does the 52/36 chainring coupled with a 11/30 cassette match up.Will it be good for a 70 year old recreational rider? Or what combo would you suggest? <Q> Highly unlikely this is the gearing for you. <S> 52/36 would be considered a higher gearing choice these days. <S> You may also want to consider bike that can take a wider range cassette. <S> 11-36 cassettes are available on road groupsets. <S> You may even want to consider a flat-bar hybrid with even lower gearing and more upright riding positions. <S> Find a good local bike shop for advice and to try out some bikes. <A> Generally speaking, it seems too high. <S> I am rather fit, a few years younger, run a 50/34 compact <S> , don't have an 11, and don't miss it. <S> but I would prefer the smaller. <S> For the low end, it depends on the hills you want to ride. <S> My low is 34/30 which does what I want, but each area and each rider is different. <S> It seems to have become easier to find 32 or 34 cogs on road bikes. <S> You need a medium cage derailleur for them and the spacings get a bit larger, but you can't use gears you don't have. <S> If you can borrow a bike, go climb some hills and see what gears you use. <A> The reality is that this is impossible for anyone to answer for a specific rider, without knowing the rider. <S> However, 2 of my favorite shop customers are people that would describe themselves as “recreational riders” but put in more miles in a year than I do by far. <S> Not least because retirement allows them to ride consistently. <S> They are both well over 70 at this point, also. <S> That said, if you are looking at a comfortable, stable road bike, and your goal is not to race your bike, then I would consider a 50/34 (compact) front end, and a 12-28 rear cassette. <S> To my way of thinking, that provides a good balance of top end speed, and reasonable climbing gears. <S> Things that will affect your decision: <S> Fitness level/body weight: The strength to weight ratio is critically important in cycling. <S> If you are 125 lbs. <S> and strong enough to push your weight up hill without losing your ability to continue riding, then erring on the side of high torque/high speed gears makes sense. <S> If you are 250 lbs, and any hill is the one you die on, then erring on the side of low torque/low speed gears makes sense. <S> Terrain: <S> If you live in San Francisco, and every direction away from your home is uphill and beyond category, then low torque/low speed. <S> Medical restrictions: There are a million things that can go on this list, but the big thing is, if you have medical restrictions, don’t push them. <S> Err on the side of easier pedaling, rather than creating issues for yourself. <S> As for how to decide what specific gearing fits your needs? <S> There are lots of choices for gear calculators. <S> Bikecalc .com is my favorite.
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It’s likely you will need a lower gearing, especially if you live in a hilly area, so consider a 48/32 ‘sub compact’ on a road bike. Well, use a gear calculator to compare the different combinations and find one that fits your needs, with the things I mentioned in mind. Standard chainrings on most drop bar road bikes are 50/34 ‘compact’. Whether you use 52/36 or 50/34 doesn't matter too much When I read “70 year old recreational rider”, my inclination is to assume relatively short/easy rides, and a fitness level which is not ideal and may include medical restrictions. If you are retired and and living in the Arizona desert, and an overpass is the biggest hill you see, then high torque/high speed.
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Should I multiply maximum tyre load by number of wheels to get maximum bike load? I bought a cheapo adult tricycle and looking closely at each tire there is stamped on it a maximum weight capacity of 175lbs. Do I multiply 175lbs x 3 for the max load it can carry or does this mean only a person weighing less than 175 lbs can safely operate this trike? Thank you very much! <Q> It is unlikely that the “weight” listed is the capacity of the tire to support weight, but more likely the maximum internal air pressure in PSI (pounds per square inch). <S> If it is weight capacity, then yes, each tire will support 75lbs, so a balanced load over 3 tires would support 225lbs. <S> That assumes equal weight on each tire, though, which is difficult to achieve. <S> Edit: <S> Since the weight listed on the side of the tire is actually 175lbs, that is much more realistic as a max weight capacity per tire. <S> That would make the total supportable weight for a balanced load 525 lbs. <A> There are a lot of factors that affect the maximum weight your tricycle can handle. <S> First, there are the tires. <S> Tires are incredibly strong but there are limits especially if you hit a pothole or rock. <S> Also, as Jeffrey Bell notes, it’s also possible to roll the tire off a wheel if you go around a curve too quickly. <S> Second, there is your rim and spokes. <S> Your rims may be a limiting factor. <S> Exceed the max weights for these and your rims break or spokes break. <S> Third, is your axle. <S> On trikes, this is a huge limiting factor because the paired wheels usually mount with single-sided axles (aka wheelchair hubs). <S> It’s very easy to bend these axles with a load that’s too heavy. <S> Exceed this and bend an axle or more rarely break the hub or bearings. <S> Fourth, your speed is a huge factor. <S> What you might be able to get away with at a snails pace won’t work at 30kmh or 20mph. <S> Fifth, your riding style will also be a factor. <S> It’s much harder to bunny hop or even shift weight on a trike which is a problem. <S> Finally, an unsuspended bike will withstand much stronger forces at the axles than one with suspension. <S> In other words, you should go by what your trike manufacturer lists as the max weight of the trike rather than any single component. <A> "Maximum tire load" reflects the maximum that any individual tire should carry. <S> For instance, with a 175-per-tire limit on a trike you may encounter the situation where the singleton tire inherently carries about 50% of the load, due to the weight is distributed. <S> This would mean that the entire load would be limited to 350 pounds, even though the paired tires each carried only 87.5 pounds. <S> If the limit is 175 pounds and the tire pressure is 35 psi, this means that the load will normally be spread over about 5 square inches. <S> This is easily accommodated by a normal tire on smooth pavement, but when you hit a bump (or a curb) <S> the tire deforms unevenly and a rim strike (or other nasty effect) is likely, because the load is concentrated on a smaller area. <A> Remember the rims, axles, wheels, frame, etc will all have their own maximum ratings. <S> For example the Walmart adult trike is a Schwinn, with an overall weight maximum of 350 pounds (159 kg) <S> according to http://tricycleworld.org/schwinn-meridian-adult-26-inch/ <S> That's excluding the 70 pounds (31.8kg!!) <S> of bike, but including the rider, clothes, contents of pockets, and anything you put in the carrier.
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As to what creates such a limit, the strength of the wheel (in particular the spokes and hub) is part of it, but also consider the deformation of the tire. As such, the bike manufacturers specifications should be the final word on overall maximum loading.
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How do I get a new chainring when my bike is so old, the manufacturer doesn't have the chainring (or crank) I need I need a new chainring but when I called the manufacturer they said my model is so old they don't have the part any more. I've attached an image of the crank from the manual and a photo from my bike. Can someone tell me if it is possible to get this type of chainring, or an entire new crank? How do I measure it to make sure it fits my bike? <Q> It seems that you're asking about a BMX chainring. <S> As far as I can see (I'm no expert in BMX) they are fairly standard. <S> To be sure you'd neet to take three measurements: the diameter of the hole that goes on the bottom bracket spindle (1) <S> the diameter of the hole that attaches to the drive-side crank (2) <S> the distance from the centre of the first hole to the centre of the second hole (3) Have a look at the attached image with those measurements marked red: As you can see, the measurement 3 is somewhat flexible with the chainring pictured. <S> With those three measurements you can visit couple of LBSes and confirm that you're purchasing the correct part. <A> You have a one-piece Ashtabula-style crank . <S> These were commonly found on inexpensive department store bikes. <S> Unless you can find a donor bike or donor parts for cheap (say at your local bike coop) <S> the bikes themselves are almost always not worth the cost of trying to repair with contemporary parts. <S> I’d look at Sheldon’s page above and try to figure out which “standard” Ashtabula crank you have and find a replacement from a donor. <S> Finding the right chainring is a particular challenge but someone with a drillpress or mill could mod one for you. <S> Otherwise, you could use a universal threadless bottom bracket (from Velo Orange or elsewhere) to put a modern square taper crankset on <S> but it’ll cost you more than $100 in new parts and <S> the original bike is likely not worth $100 unless it has sentimental value. <A> You have what is called a one-piece or 'Ashtabula' crank. <S> Don't ask me why it has that name. <S> Info on Sheldon Brown here: <S> https://www.sheldonbrown.com/opc.html . <S> Unike cars, bicycles generally use common standardized and commoditized components that do not have to be replaced with the exact part originally used. <S> According to Sheldon there are a couple of sized of bearings used, but the bottom bracket shell and chainring center hole and drivepin are pretty standardized, so you can either replace the whole crank with new bearings or just the chainring. <S> You'll need to remove the crank to replace the chainring. <S> Park Tool has a video on how to do it: .
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You can absolutely find replacements for these cranks and chainring.
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Are there valve caps that show the tire pressure? I saw these valve caps for cars, set at 2.4 bar: Is there something similar for bicyles? it would help less careful riders when it's time to pump more air in them. <Q> These types of valve cap gauges aren’t recommended - either for cars or bikes. <S> They work by bypassing the schrader valve in the tire and using a cheap spring-based pressure gauge in the cap. <S> First, they’re wildly inaccurate even on cars. <S> By the time they show red, you’re riding on your rims. <S> Second, they’re cheaply made and a significant second point of failure. <S> If the cap is just a bit loose, the o-ring gets just a bit of dirt in it, or the valve cap gets knocked the wrong way, they will start bleeding air. <S> This is most likely why they aren’t sold in the higher pressures that bikes would need. <S> Finally, as @Argenti noted, many riders adjust their tire pressure depending on the road or trail conditions or their desired degree of ride comfort. <S> Most bike tires can take a wide range of pressures, unlike cars which have a very narrow band. <S> Conclusions: I’d just get used to squeezing your tires (for the lower pressure of mountain bike and comfort bikes) <S> and/or topping off regularly (especially if you have a road bike). <A> I think RoboKaren's answer is on point about avoiding those cheap gauges which will probably cause more problems than help. <S> From the press release : Quarq, SRAM’s data and digital technology brand, today announced the launch of TyreWiz, the first-of-its-kind tire pressure sensor for road and mountain bike riders. <S> The real-time monitoring device – designed to help riders reduce tire wear, improve compliance, and boost speed – is being debuted at Sea Otter this week and will be available on June 1 exclusively on Quarq.com. <S> The two-sensor package will retail for $199. <S> It does have a pass/fail indicator lights, with the threshold pressure set by the smartphone app. <S> The application is definitely focused towards "pros" who want to finely tune pressure or monitor it during events (e.g., gravel races). <S> Once installed, TyreWiz relays tire pressure data to a cycling computer or a smartphone every second. <S> The TyreWiz app provides personalized recommendations and pressure alerts. <S> For the first time, riders will have the ability to use highly accurate real-time information to make decisions that can affect rolling resistance, traction, tire wear, and rider comfort. <S> The real time continuous data stream suggests they are only intended to be run for events not as an everyday, day in an day out monitoring device. <S> The "long" run times are 300 hours, or 12.5 days of continuous monitoring. <A> These now exist: https://www.worldwidecyclery.com/products/quarq-tyrewiz-air-pressure-sensor-for-presta-valve-pair (smart pressure sensor) <S> They talk with your head unit or smartphone. <S> They have LED lights that tell you too low/high as well.
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For completeness sake, I point to the fact that the only "bike-specific" tire pressure monitors on the market appear to be high-end wireless digital versions that send data continuous monitoring data to a smartphone. I think the easier option will be to pump your tires up to your desired pressure, give a thumb press to see how hard they resist and occasionally conduct a "squeeze test" as suggested by RoboKaren.
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No space inside the house, where do you store / secure bike? I live in the UK. At my house, I don't have much space, I have a drive-way but no gate surrounding it. Here's an image: What are my cheap storage options for a mountain bike (voodoo bizango). Thanks <Q> You can get wooden storage sheds for bicycles for around £150 - £200. <S> You'll also need something to secure the bike to. <S> You could install a ground anchor, either the screw in type: <S> Or the type that you embed in concrete: <A> Storing a bike outside leaves you with two problems to deal with: thieves and weather. <S> No perfect solution for either problem exists unless you build something around your bike that starts qualifying as storing it "inside". <S> Against theft, use the biggest chains and U-locks that you can find to bound your wheels and saddle, use anti-theft QR skewers for axles. <S> Lock the frame to the burliest stationary object you can find around. <S> I do not see any reasonable candidates on your picture though. <S> You might just want to install your own bike rack by screwing it down to the pavement with huge bolts. <S> Against the weather, provide some protection against the rain by covering the bike with a tarp. <S> You cannot protect it against low temperatures outside, but direct water contact is by far the worst. <S> Make sure the tarp is well fastened to not be blown away by a strong gust of wind. <S> A cage would be good enough only if it is made of steel bars 10 mm or more in diameter (otherwise it would be easier to cut it than a lock on its door). <S> I can imagine that one big enough to fit in a bike (2 meter × 1 meter × 1,5 meter) would cost more than a decent bike rack. <S> On a plus side, it might possibly be so heavy that it would not require bolting it down to the pavement. <S> And then you can make a roof for it and it will become storing a bike inside. <S> Or just suck it and bring it inside your home and hang it from the ceiling or disassemble it before storing. <A> Since you’re from the UK, I’d be remiss if I didn’t suggest you get the greatest folding bike ever invented, the Brompton: <S> But if you already bought a bike, you might want to look into storing it in your house either horizontally: Or vertically. <S> The vertical stands in particular take up little room:
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You might still want to consider finding a place to store an expensive bike inside, like renting a storage room or an underground parking spot somewhere nearby. Finally, as @Daniel Hicks notes, it's also possible to buy and mount a pulley system that will let you lift the bike to the ceiling, either horizontally or vertically.
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