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What are the benefits of nickel-plated chains? Bicycle chains with higher model numbers (and slightly higher prices) are often nickel-plated or half-nickel-plated. What are the benefits of nickel-plated chains over non-nickel-plated chains? How durable is the plating--does it wear off, or do its benefits last for the life of the chain? <Q> Nickel plated chains have this done for aesthetic purposes, and to provide corrosion resistance. <S> They are also less susceptible to the chain binding itself up. <S> When two metallic surfaces create friction against each other, they create small areas of abrasion <S> (Much like a plaque in your arteries). <S> Over time, these increase to the point where the chain can kink in spots. <S> Nickel helps to stave this off. <S> The wearing may be slightly higher than with a non coated chain, but the difference to the lifespan of the cogs (cassette) is negligible. <S> Chains should be replaced around the 2500km mark on a regular basis, and cassettes anywhere from 5000-10000km depending on many factors. <S> You'll go through 2-3 chains per cassette, and usually I replace my cassette with every 3rd chain no matter what. <S> Dust/dirt/mud and poor maintenance will do more harm and accelerate wear faster than any plating on the chain will. <A> As stated above, the main reason for nickel plating is to stop rust. <S> Personally I would only want the nickel on the outside surface of the chain. <S> The reason is some modern nickel plating (though I admit I don't know if this is the case with bicycle chains) is harder than steel and so would wear the sprocket and chain-ring faster if the plating is on the inside of the links. <S> I would rather wear out an inexpensive and easier to replace KMC chain than a pricey 10 speed <S> Shimano XTR cassette! <S> Kinda like on my old TV how I would prefer it not to blow a $200 picture tube (back when $200 was a lot of money) to protect a 10 cent fuse! <A> The main benefit is corrosion resistance at a slightly higher cost. <S> Plus the near chrome like finish looks better. <A> Drew was really the only one to hit on friction, but that's a big factor to consider for nickel plating benefits. <S> To borrow directly from the words of a company that specializes in plating , benefits include: Excellent Corrosion Protection Wear Resistance <S> Good Diffusion Barrier Surface Hardness Magnetic Characteristics <S> Obviously some of these bullets are more beneficial than others to the application of bike chains. <A> Most of the bicycle chains are made using some form of steel/steel alloy. <S> Nickel is an essential element in forming stainless steel, the reason to add Nickel is to retain the austenitic structure(a type of crystalline structure) for wide range of temperatures. <S> Stainless steel has the appearance of a nickel-plated chain, but will still retain the look when old and used(kept clean of course). <S> Unlike steel; the nickel-plated chain's plating may get worn off due to use and appear as though paint has chipped away. <S> You may also see some chains that have special electro-plating of chromium/nickel, a.k.a dripping chrome trying to be aesthetic. <S> Nickel plating on metal is known to provide corrosion resistance and has lubricant effect. <A> In the gun world, companies will coat the reciprocating parts (mainly the bolt) with nickel-boron to reduce friction, going so far as to claim that you don't need lubricant. <A> This article explains more about each benefit <S> There's a bit more information about nickel coatings on this website too. <S> Hope that helps! :)
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The main benefits of nickel plating for bike chains are hardness, corrosion resistance and wear resistance. Lubricity Tarnish Protection Decorative Appearance
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Converting Mountain Bike for Road to complete in 33 mile mini triathalon I have a very good mountain bike and like to ride trails. I recently signed up for a mini triathalon that requires a 33 mile road ride. I don't want to buy a new bike, so I was thinking about buying a new set of rims and swapping them out for this race. Not very experienced with converting, so looking for some help on solutions. Don't want to spend a ton of cash on this either. <Q> Even if you do not go as far as different rims, consider different tires. <S> Slicks (1.25") vs the regular tires (2+ inches) will make a huge difference, and usually can be found for $30 a tire or so in the US or Canada. <S> Beyond that, remove unnecessary hardware. <S> Front shocks are probably the worst thing you might have on the bike. <S> I do not know if it is worth considering a hard fork just for this race or not. <A> Would absolutely go along with @geoffc's answer re tyres. <S> I'm suspecting that's what you really meant to type when you said "rims"? <S> But anyways... <S> I'd just add that it might be worth trying out some aero bars too, you can get ones that will just clamp on to your current bar. <S> Might be worth seeing if you could borrow some first as they are very much an acquired taste, but you can imagine they'd improve your position on the bike if you can get on with them. <A> If possible, just rent a road bike. <S> Even though you can make a mountain bike more comfortable for road riding, the frame itself is completely different in terms of both geometry and weight.
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You'll be a lot happier if, instead of spending a bunch of time and money messing with your mountain bike to make it not horrible on the pavement you instead spend about the same amount and just rent a road bike for the event.
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Learning to ride fixed gear: Clipless or not? Which strategy is better for learning to ride fixed gear, if you're already comfortable with clipless pedals: Flat pedals at first, clipless after you're comfortable with being unable to coast. Learning to ride clipless from the start, probably with the tension turned way down. Just got a fixed gear bike, which I plan to practice riding in a park for a while before using it as a commuter. I usually ride with clipless pedals, and I gather from questions on SE as well as other sources, that foot retention is quite important on a fixed gear as well. Thus, eventually, I would want to ride that way. <Q> Here's my experience: <S> The biggest problem in starting to ride fixed is that my brain would forget I was riding fixed, I'd come across a decent stretch of road (or a corner), and would attempt to coast. <S> All totally subconsciously. <S> With flat pedals, provided I was doing a decent enough speed/cadence, I'd end up having to take my feet off the pedals until such time as I'd slowed the bike enough to get my feet back on and essentially regain control of the bike. <S> Timeframe possibly 10 seconds during which the only real control I had was to steer and brake. <S> In clipless pedals, however, because my feet are attached to the pedals, as soon as my brain says "coast", my feet say "whoaaaaa". <S> My brain then kicks back in and because I am still attached to the pedals I can just recover, easy as. <S> And the timeframe here is just a fraction of a second. <S> So for my money, and assuming you do have a traffic-free environment in which to hone your skills, I'd go clipless straight away. <S> But this of course is a preference thing rather than a technique thing. <S> btw, even though I've had a fixie for a couple of years now I still fall into this trap. <S> Right now I'm probably only getting the fixie out once a month (compared to riding geared bikes several times per week), so there's an element of readjustment every time I take it out. <A> I think clipless pedals are definitely the way to go. <S> I find the first time I ride it after having ridden freewheels for a while <S> I'll forget once or twice and get a bit of a jolt through my trailing leg to remind me to keep those pedals spinning. <S> Also from Sheldon Brown's site : <S> Sometimes, novice fixed-gear riders will try to use plain pedals with no form of retention system. <S> I strongly advise against this. <S> Riding fixed with plain pedals is an advanced fixed-gear skill, only recommended for experienced fixed-gear riders. <A> Foot slipping off the pedal unexpectedly can result in a worse experience than the maybe dead stop tip over. <S> Check out PowerGrips or the Fyxation <S> (?) <S> stap system. <S> Conventional clips with loose straps on cleatless shoes are the simple route & allow for quick when needed foot removal. <S> Practice track stands. <S> Outside of practical <S> it's a basic skill. <S> If riding hilly terrain you might just want to consider going flip-flop freewheel side. <S> Longer or steeper pitches can be tough on the knees and/or tires. <A> As previously mentioned, foot retention is essential for safe fixed-gear riding. <S> I started off with clips and straps, but after breaking a few during hard climbs, I switched to clipless. <S> But then I ride a long gear and really haul my bike up the steep hills around here. <S> I definitely appreciate the security and efficiency of clipless, but it's by no means a magic bullet. <S> I've sheared cleat bolts on climbs too. <S> If you're going to ride brakeless, then I would definitely go with clips and straps, or a PowerGrips-type solution. <S> I rode brakeless for about 4 years, using Time ATAC pedals. <S> They were pretty dependable; I wouldn't trust many other pedals for brakeless riding. <S> But I still had a few hairy moments... <S> accidentally unclipping isn't funny. <S> If you get slack with your skidding technique and twist your feet, you may find yourself going over the bars (as happened to me a couple of times), or worse, straight across a junction and under a bus. <S> Perhaps even more relevant: <S> if you're riding fixed around town on a daily basis, can you really be bothered to lug around two pairs of shoes? <S> If you're on and off the bike a lot, you're going to wear down those cleats pretty quickly!
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With the pedals always moving under your feet, it's even more important to have your feet firmly attached as it's too easy to lose contact with the pedals otherwise. In traffic, I prefer flat pedals, just because I might want to put my foot down, like, now .
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How to remove rust from unpainted parts? I would like to remove rust from some old parts such as cassette, bolts, and nuts. Most of the rust is just surface rust, and I would think there would be a good technique for doing this. Besides using steel wool, I have heard of either using ultra-sonic washer or an acid bath. What is the best way to accomplish this? I would prefer to stay away from chemicals. <Q> The best way to remove rust from steel or cast iron is by electrolysis, period! <S> See the links below, but a few points need to be emphasized first: <S> DO wear rubber, latex or other waterproof gloves <S> DO wear old clothes, cuz the solution will stain just about anything! <S> DON'T put the solution where it can be kicked or spilled, it will leave a killer stain! <S> DON'T hook up what you are removing the rust off to the positive (+) terminal! <S> And most critically important <S> DON'T USE STAINLESS STEEL <S> AS THE ANODE (+ electrode)!!! <S> Ok, now to the links that explain the method: http://antique-engines.com/electrol.asp <S> http://www.rickswoodshopcreations.com/miscellaneous/rust_removal.htm <S> A few suggestions. <S> Use no more than 6 volts, particularly if you don't want to remove paint. <S> Use washing soda (sodium carbonate, aka NaCO3) as the ingredient, not salt or lye. <S> Small quantities of NaCO3 can be made by heating baking soda spread on a cookie sheet for 300 degrees F (150C) for about 1 hr. <S> Don't pour the old liquid on your lawn or garden, the sodium could damage the soil. <S> The solution is safe to pour down a laundry or basement drain, but be sure to wash out the drain afterwards. <S> At most only 1 tbsp per gallon NaCO3 is needed - using more is just a waste. <S> If you use an old wall-wart, the negative is usually the wire bearing a white line or bead on it and is usually hooked to the outside ring on the outlet plug. <A> It works with steel parts. <A> A common deburring machine used for mass finishing parts is a vibratory deburring machine, or vibratory tumbler, which utilizes abrasive media to deburr, clean or polish unfinished or dirty parts or objects.
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A simple trick that works to remove thin rust is to rub the rusty part with aluminum foil.
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Hybrid electric bikes, how do they work? I'm about to move further away from work, so my 5.5 mile commute is going up to 12 miles (24 there and back). I'm not interested in using an elecrtic bike because I can't be bothered to pedal.. I want to use an electric bike to speed up my commute to work and back. I estimate that on my racing bike it'll take me approximately 45 mins to get to work. If I got an electric bike, is it possible to use the motor to assist me rather than do all the work? If so, what sort of time saving do you think is possible? Do they offer much oomph? I have my eye on one of the giant electric commuter bikes but I don't really know what to look for. I'm not sure yet if there's actually going to be any speed advantage hence I'm asking :) Update : 3 years later, I never did buy an e-bike. I stuck with my road bike and just powered on through. I can now average 20mph if I feel that way inclined. I'm also the fittest I've ever been so I think all in all e-bikes aren't for the likes of me. I did however buy a new, faster road bike but the real speed comes from stronger legs/mind. Update 2 : I did get an ebike in the end! A cyclotricity 1000w stealth. It saves about 45 minutes as there's no need to have a shower at the end of the ride and it's faster. It's good! <Q> The class of bike you're looking at is called an Electrically Assisted Pedal Cycle, a brief summary of the law regulating these is available here . <S> In the UK (and Europe): maximum power is 250w maximum assisted speed is 25 km/h (15.6 mph) <S> You don't need insurance, a driving license, Vehicle Excise Duty or a helmet to ride an Electrically Assisted Pedal Cycle. <S> It's possible to get electric bikes with more power and / or a higher speed limit. <S> These would be classified as a moped and would need insurance, driving license, etc. <S> You also couldn't ride them in cycle lanes and cycle paths. <S> The linked article describes the legality of these as " at best, questionable ". <A> So right after my hands-on experience I can say that an electric bike will give you no speed advantage (presuming you are moderately fit). <S> The acceleration is really quite extraordinary. <S> Even in the highest gear you can just pedal away. <S> I tested on highest power mode seeking best performance. <S> The problem, as Tom77 and others mentioned, is top speed. <S> It stops helping after around 26mk/h. <S> And after it's just heavy and uncomfortable to ride. <S> With a road bike you can go so much faster. <S> Also - imagine your battery dies? <S> Can't be fun hauling that heavy bike up a hill. <S> I tested a womans bike, it was way too small. <S> I reached top speed 35 km/h with some effort (in saddle). <S> With my road bike I'd cruise that speed easily and feel comfortable. <A> My wife and I have the Kalkhoff <S> Pro Connect Sport 250 . <S> I purchased mine to reduce my commute time. <S> My commute is 12.5 miles one way with some pretty good hills in the mix. <S> On my regular bike it takes an hour to an hour 15 but on the Kalkhoff it only takes 40 minutes. <S> This bike is a Pedelec in that you must pedal for it to provide any assistance (although it does have a mode where it can power itself at slow speeds when pushing up a steep hill - typically used to push beside stairs in Europe where they have dedicated rails for that purpose). <S> I can typically maintain an average of 20 mph over the commute with speeds on flat sections around 25 mph. <S> With a racing style bike you may be able to get more speed as the wind resistance is the real limiting factor at this speed, although with this bike I will pedal out at 25-30 mph. <S> There are other models that have a three speed hub shifter that would allow more speed without pedaling out. <S> It looks like they have limited supply right now, but I'd encourage you calling them directly as they have been very good answering my questions and following up on service issues. <S> Plus, you can order the bike and return it within a week at no charge if it isn't right for you.
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Some Electrically Assisted Pedal Cycles come with an "off-road" mode which removes the speed limit.
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Messenger bag or handlebar basket? Fairly straightforward question the answer to which I presume depends upon ride distance, terrain, bike type, and bag weight, but I'm hoping there's a rule of thumb that generally applies to all scenarios. This question dawned on me as I was mounting a Citi Bike last night: Should I keep my messenger bag (weighing about 15 lbs.) strapped to my back, or should I secure it in the "protective rack" attached to the handlebars? My thinking at the time: The bag would fit perfectly, but it would weigh down the front of the bike and make it more difficult to steer. I opted to keep the bag strapped to my back, but this decision was based on 100% conjecture. I have little to no experience riding with belongings in a handlebar basket. On the other hand, I very often ride with a heavy messenger bag. It's habit at this point, and maybe a bad one. The ride proved uneventful, though I can report that it isn't exactly easy riding the incline of the Williamsburg Bridge while wearing a full messenger bag on a 45 lbs Citi Bike. Would the ride have been any easier if I had put my bag in the handlebar basket? <Q> Bikeshare bikes are beasts, and their geometry (long wheelbases, particularly) is such that I wouldn't think 15 pounds in front appreciably changes the steering. <S> My concern -- the picture isn't clear on this point -- is whether the bag can be secured in place so that it doesn't slide out. <S> My messenger bag sometimes gets loaded unevenly (books!), which could increase the chances it would fall out. <S> Heat is another consideration, especially given that hill. <S> Messenger bags on your back hold in the heat! <S> Hill might not be any harder that way, but it'll likely FEEL sweatier and more difficult. <A> I would suggest that you strap it to your back ONLY if it is not distracting you when cycling. <S> What I mean by distracting is the back sliding left or right and making you feel that it is moving around your body. <S> This could be an annoying factor for just anybody. <S> If you have this issue, try to fasten it around the protective rail at the front. <S> Citi bikes are reasonably sturdy, so the weight distribution would not be affected I hope. <S> We have similar bikes in London and I am sure I have seen people doing both; bags strapped around the body and fastened securely around the front area (where the protective rail is). <S> Why not just try it? <S> I would certainly do that. <S> P.S. Make sure you secure it properly if placed around the protective rails at the front. <S> You don't want your bag to be accidentally slipping away on a main road during rush hour, especially if you have a laptop or PDA inside :P <A> Wearing it on your person would keep the center of gravity more at the center of the bike where it should be. <S> I used to have a paper route when I was a kid, and needed two bags of papers over the rear carrier on average days, but when the papers were larger on coupon days, an extra bag was needed on the handlebars for about a dozen papers, and just that 4 or 5 pounds made the bike handle much differently until those papers were delivered at the start of the route. <S> If it does, maybe a regular hiking backpack of the proper size would work better than the messenger bag.
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Just make sure your messenger bag is secured to your back and doesn't slide around.
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Why are people with full suspension bikes concerned about 'Stiffness' added by thru axles? Why are people with full suspension bikes with several inches of travel be concerned about 'Stiffness' when discussing the advantages of thru axles. I would think this is more of a concern for rigid bikes which don't have suspension. Isn't the advantage that you're just less likely to snap the axle when riding down a gnarly trail not really how 'stiff' the axle is or does this have some other purpose? <Q> Thru axles not only keep the wheel in place, they also strongly join the right and left dropouts together. <S> This structurally reinforces the component either being it a fork or a rigid/suspended rear triangle. <S> This simply makes the bike able to handle greater forces before failure, because it distributes forces between both sides of the structure. <S> It also avoids twisting of the parts. <S> For example, if one arm of a fork twists, it means it may loose alignment relative to the other, thus meaning the wheel is not pointing in the direction the handlebar tells the rider, this leads to a bad feedback and imprecise ride feel. <S> A thru axle keeps both sides of the fork aligned, eliminating (or reducing) this issue. <S> It also keeps the pivots aligned, thus giving them a longer life for both bearing type or bushing type pivots. <S> The bottom line is that a stiffer structure is more efficient and gives better feedback to the rider, allowing for a more confident and precise ride. <S> It also allows a lighter bike to handle greater forces. <A> Stiffness in this context is the ability to resist twisting and bending forces caused by turning and heavy braking (usually on difficult ground). <S> A stiff shock moves up and down freely but allows no twisting or bending back and forward/side to side. <S> MTB riding benefits from stiffer forks. <S> The main advantage is the precision of tracking by the front wheel. <S> As an over simplification, think what happens when the forks twist - the front wheel no longer points in the same direction as the handlebars. <S> On difficult ground this can change in a split second, making riding more difficult. <S> In the extreme, a flexible fork can throw a rider offline, as best, slowing him, at worst, causing a prang. <S> For decades the 9mm QR was the standard for virtually all wheels. <S> As MTB forks became longer travel and lighter, and riding more extreme, it was decided that a stiffer connection between the hub and fork was required. <S> The 20mm through axle was developed. <S> This was rejected by many as too heavy, so the 15mm Through was developed as a lighter weight alternate providing nearly as much stiffness as a 20mm, and virtually no more weight than a 9mmQR. <S> There are few benefits for a through axle for all but the most extreme or elite riders. <S> The additional strength is a benefit to the most extreme downhill riders. <S> The additional stiffness is the only other real benefit - therefore, any discussion on through axles is incomplete without mentioning it. <S> Many believe the offer little advantage and many disadvantages over QR for a majority of riders, and are more a marketing gimmick than a real advance in bicycle performance (for average riders). <A> The stiffness in the front added by the 15mm or 20mm thru axle is very important because it lets the bike go through very rough sections (roots, rock gardens, corrosed terain) without transmitting unecessary feedback on the handlebars. <S> This makes fast riding on rough terrain easier and safer. <S> In addition, a stiff axle will not allow the wheel to bend laterally too much, even on a smooth terrain, when going fast on a bermed corner etc. <S> This gives more presision and less lost energy. <S> In any case, snapping an axle, even a 9mm, should be pretty hard. <S> That is unless something has not been set up correctly.
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For suspended rear triangles it also makes the structure stiffer, this allows better distribution of forces through the stays, so those forces reach the shock absorber with better alignment, also allowing for smoother operation and longer component life. There is some controversy around the need for the smaller through axles on all but the very best bikes. It also keeps the lower ends (bottles) better aligned with the upper parts (stanchions), allowing for a smoother operation and longer life of seals and bushings. The stiffer the fork, the more precisely the front wheel can be placed.
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The right saddle for touring In a month time I will be doing a two week tour in southern France. I was wondering which is the best kind of saddle for touring? I have a Specialized Tricross that came with a modern narrow and not so cushioned saddle with a hole down the middle (any idea what this is for?). I also have a Brooks saddle B66 (with springs). Now, I love this saddle but I've been told that it is preferable to use one without springs and that is not so wide for longer rides. Exactly why I don't know... Any idea, comments, etc very welcomed! Thanks!! <Q> The best kind of saddle for touring is one which <S> you find comfortable. <S> The cut-out is intended to relieve pressure from your soft bits leaving most of your weight on your sit-bones. <S> A saddle is a personal choice and there is certainly no one ideal, "best" touring saddle for all people. <A> You need more than a couple of weeks to determine if a particular saddle is "comfortable. <S> " If you like the Brooks B-66, then by all means use it for the tour. <S> All saddles, leather or not, must be "broken in" to some degree. <S> Making sure your saddle heigth, fore and aft position to your knees <S> being centered on the pedals at the right moment to keep your hips from swaying, and the tilt of the saddle, level or nose slightly up or down, is all important and can determine how your saddle "feels." <S> That cutout in the center of the saddle is to relieve pressure from your Perineum area while in the saddle. <S> It also adds some ventilation and cooling for that area. <S> Some people say this works while others don't notice any difference. <S> To me, this cut out area would tend to weaken the solid structure of the saddle. <S> Leather softens over the years if well cared for, and it seems to me this cut out area may change and get wider if it begins to be pulled towards the edges of the saddle. <A> Saddle width depends on: sitbone width, and riding position. <S> Usually touring is done in a more upright position, which requires a wider saddle vs. the same person in a sporty position. <S> The hole in the middle is for your crotch. <S> If that bone hits hard plastic/metal, it hurts a lot, and you cannot ride more. <S> The B66 is a good choice for touring, probably it has already the right width and crotch "valley" for your body geometry. <S> See my post here for more on width: Brooks leather saddle break in <A> I have done many tours on a Brooks B17 and it has been great. <S> Something you may not know is that many urban bike shops allow you to try a saddle on your own bike before you buy it. <S> Many also have return policies on their saddles if you do buy it and bring it back in good condition. <S> This is a great way to make a decision about non-leather saddles. <S> Since leather saddles have a break in period before they feel great, they can be hard to judge so quickly. <S> (Think about breaking in a baseball mitt or leather boots.) <A> My Terry seat with the hole in the middle saved me when I rode across the US.
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That said, I agree with a previous post that says use the saddle that is comfortable to you . Given that you "love" your Brooks, I'd suggest looking at another Brooks (maybe a narrower one), or if you're confident it will be comfortable over longer distances, use your B66. A very wide saddle might start to rub excessively inside your thigh on a long ride, while one with springs may be too bouncy at higher cadences and waste some of your effort.
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How do I identify an SR SunTour fork exact model? I recently located this SR SunTour service manual , containing schematics of a load of forks. Trouble is, my fork only has "XCR" on a sticker, and production date stamped. At some forum this is discussed and links are provided to SunTour's XCM, XCR and XCR product lines. Strangely, my XCR does not match visually any of the presented (mine has no V-brake option). Am I supposed to find a model number stamped somewhere on the fork , as with most other bicycle components, or should I deduce which fork it is from the features e.g. wheel size, brake options, outlook, locking and adjustment mechanisms. I would be quite surprised if the model is not stamped. How do bicycle mechanics deduce the model - do they know them all from experience? <Q> The fork should have a serial number. <S> Not obvious and a little small and faint, something like tb0111xxxx. <S> Mine was located on the lower assembly. <S> Go to https://www.srsuntour-cycling.com/service/ <S> enter the number and it should come back with model type and year of manufacture. <S> From that you should be able to find the exploded view pdf. <A> On Suntour's XCR page you'll find some pictures of forks that have both disc and v-brake mounts. <S> However if you press "Show more details" you can read on the bottom of the details column: "Note Disc only type bottom case available". <S> I also have an XCR and the model is nowhere to be found. <A> A easier way may be to look up your bike year and model on bikepedia , the site is both detailed and accurate.
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You have to try and deduce the model. The same model can have two different bottom cases which support disc and v-brake or just disc mounts.
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Can small pebble inside tire puncture the tube? Shortly after changing a flat in a dirt road near home, I got another one. This last tube got a very small puncture. Inside the tire I also found some small pebble (like 1mm or less in length), but no thorn or wire. I wonder if this small gravel trapped inside the tire can puncture the tube? <Q> If the pebble was sharp, it definitely could be the reason. <S> Using sealant tubes could be another great idea if your main riding is off road (I think that without them I would be changing tubes two times a ride). <A> More likely you punctured the tube while installing it. <S> You have to be careful to not pinch the new tube between the rim and the tire. <S> Also take care not to puncture the new tube with your tire levers. <S> When changing a tire I'll inflate it the tube about 50% and then peel the tire around to make sure the tube is not pinched. <S> Then I deflate and the reinflate to recommended pressure. <S> I use plenty of lube on the bead too. <S> That can be water or better but grosser, spit. <A> The amount of friction between the casing and a tube is impressive, especially over time (there's a photo out there that I tried to find to illustrate it but failed- if anyone can find it feel free to edit), but if you don't see an obvious spot where it looks like the tube "wore through" then you probably had a puncture where the offending object simply fell out.
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Each time before you change the tube, check the tire from the inside for any thorns that stuck or (something that happens quite often) glass particles that left inside.
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Training Wheels for an Adult I have a friend that refuses to attempt to learn to ride a bike without training wheels/being a tricycle, despite being 22 years old and an avid jogger..... I have an 30 year old touring bike, and a hybrid that is more on the mountain bike end of things. I've noticed that adult training wheels are horribly expensive, and I don't have $200 to blow on a set. I've come up with some crazy ideas that I might discuss with a professor from my engineering mechanics class, but does anyone have an affordable way to set up training wheels on a "typical", if you will, adult bike? <Q> Don't. <S> To someone with reasonable balance learning to ride, using training wheels impedes learning. <S> For infants, the balance bike toys are great, but they are not available in adult sizes. <S> Instead, remove the cranks, bottom bracket, derailleur and chain from a normal bicycle. <S> Ideally choose one that's a little on the small size for the adult so that the crossbar is lower and the handlebars closer than usual. <S> Using a cheap/reclaimed bike means reassembling it afterwards isn't an issue, which is handy since old, cheap bikes are often really painful to put back together (and you'll probably end up buying new cables, chain and possibly bottom bracket anyway). <S> That setup lets them get the hang of balancing and steering with the safety of being able to put both feet on the ground easily. <S> Answer: try falling on the grass. <A> You don’t learn cycling with training wheels. <S> The most difficult part of riding a bike is keeping balance and making a turn, not pedaling or braking. <S> When you have appropriate speed, an experienced cyclist performs a steering manoeuvre called countersteering (although most of them are not aware of that): <S> In order to turn left, you push the left bar handle (yes push, not pull). <S> That way you "fall" to the left and at that moment physics kick in and you make a nice left turn. <S> If you have training wheels, you are learning the exact opposite: if you want to turn left, swing your steer to the left, if you want to go to the right, swing it to the right as if you are in a car. <S> So you'll have to re-learn cycling again once the training wheels are dismounted. <S> Learning the hardest part (keeping your balance and steering) can best be done on a low bike with the pedals dismounted, using your feet to make speed. <S> If he is experienced in that, just remount the paddles back and off <S> you go! <S> Source: <S> Living in the Netherlands, father of four kids that could all ride a bike at the age of three (without any use of training wheels) and being an active motor bike rider. <A> Why would you blow $200 when it's the friend that refuses to learn to ride? <S> Tell this person to get a 24" wheeled kids bike from a thrift store for 15 bucks and take the cranks off to turn it into an adult coaster bike. <S> That wouldn't look any more ridiculous that an adult riding a bike with training wheels, and it would actually teach this person how to balance on a bicycle.
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Training wheels can be effective if someone has balance issues, but for those people a tricycle is normally a better approach. If you don't have the tools a bike shop should be able to do this cheaply. Do it off the street, obviously, preferably in a park with grass available to deal with the inevitable "what if I fall" question.
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Are there road bike tires invulnerable to popping? I am a mountain biker now living in Minneapolis and so I bought a road bike, but I can't keep tires on it to save my life. I 'upgraded' to Continental Attack/Force tires, got a glass shard in the rear, and now just went over a pothole that popped both the front Continental and rear stock tires. I haven't even been able to even ride a mile on it. At this point, I'll take heavier wheels with more rolling resistance just to be actually able to ride. Does anyone make solid rubber or non-pneumatic tires for 700c wheels? These look neat, but they aren't being produced yet: Side note: I like to drop and hop curbs (though I haven't even been able to attempt it on the road bike), there are frequently metal shavings or other sharp objects on my garage floor, and I live in a neighborhood with lots of cracks and potholes. Should I just give up on road bikes and stick with my mountain bike? <Q> At risk of being downvoted, you don't want want solid tires. <S> There's a reason that all performance tires for all vehicles are pneumatic. <S> The decrease in compliance of a solid foam or rubber tire just doesn't compare to a pneumatic tire. <S> Look into a tire with kevlar reinforcement- <S> You may even want to try a tire sealant like the one made by Stan's NoTubes, though if you're running tubes you'll need the kind with removable valve cores. <S> If you're riding to the right of the white line (assuming you're in the US), ie on the shoulder then you're going to get a lot more flats. <S> The shoulder is where all the debris accumulates even if the road looks clean. <S> For many road riders, especially those who are just starting and don't feel comfortable riding on the road, simply switching from riding on the shoulder to riding to the outside of the actual lane alleviates a substantial portion of flat issues. <A> Use the widest tire that will fit on your bike and inflate it to the max recommended. <S> I used Bontrager Hard Case for some time for commuting. <S> They suffered fewer flats than most. <S> A added a liner & slime tube both of which helped. <S> I ride by an auto body shop that uses the street as a work area so you can just imagine. <S> I tried a solid rubber tire from http://www.airfreetires.com/default.asp <S> but I will tell you I was not happy at all. <S> The not only was the ride godawful but the road resistance was very high. <S> I wasn't expecting the latter but it was unmistakable. <S> What killed it totally was that they cracked in the cold weather. <S> IMHO <S> they are a complete waste of money. <S> Bontrager + liner + slime tube was reasonable <S> but I still got more flats especially in the rear than I wanted as a commuter. <S> I ride every day rain or shine. <S> Flats make you late. <S> The widest tire that would fit on the rear of the road bike was a 24C IIRC. <S> I recently purchased a Specialized Sirrus Elite hybrid which I adore so much <S> I also use it for long rides. <S> I may just ditch the road bike. <S> I'm using 28C rear and 32C front right now. <S> I've had Two flats since I purchased the bike in <S> I think it was March & <S> never a flat on my way to or from work. <S> If a tire can be inflated to 90psi or more road resistance is not a problem. <A> Is your problem the tires themselves or are you getting pinch flats? <S> If you don't have a floor pump you may not be inflating to a high enough psi to prevent flats. <S> When I first got on my road bike I kept getting flats and shredding my sidewalls. <S> It was because I was trying to inflate with my frame pump. <S> Got a floor pump and problem solved. <S> If that isn't the issue - I've had pretty good luck with my specialized armadillo tires. <A> I found Continental Gatorskins to be a very reliable tire through a variety of different urban conditions (I live in Montreal, a land replete with potholes, and my ride to work takes me through a light industrial area that has plenty of mechanic shops spilling their debris onto my path). <S> The suggestions I can give are: 1. <S> always have a spare tube, levers and a CO2 pump for the inevitable flats.2. <S> ride around potholes if you like your wheels and body. <S> It's a road bike not a mountain bike <S> so don't expect to be hopping everywhere3. <S> Keep a floor pump at home and ensure that your tires are inflated every week or so. <S> Keeping high pressure, not hitting the holes, and tough tires have kept me flat free... but that spare tube etc. are worth their cost in reducing my anxiety levels. <A> Use Rhinodillos Tire Liners or a similar product. <S> These sit between your tire and tube and will significantly increase puncture resistance. <S> Then make sure you keep your tires at the right pressure. <A> Just like @user7373 <S> and I'm really happy with them. <S> They have survived a couple of sharp glass punctures (the outer case has a deep cut but the inner kevlar band is still unscathed). <S> I would also recommend to use the widest tyre you can fit on your rims, I use 27mm and they are a little bit more resilient than the usual 23mm wheel <S> (if you're on 20mm race tyres you're just asking to get a wrecked wheel) <A> Sweep up your garage floor already and keep your tires at maximum pressure. <S> I live in Minneapolis, ride a surly cross-check, and rarely have flats.
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most brands have them- or aftermarket anti-puncture tire liners that sit between the tire casing and your tube. One last thing to note is that the number of flats you're getting may depend on what part of the road you're riding on. I use Continental Gatorhardskins on my road bike
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How can I use a bent seatpost to move my cruiser's seat farther back? I realize this isn't everyone's taste, but indulge me for a moment... I just bought a beater cruiser bike on craigslist, and I'm trying to move the seat farther towards the rear of the bike for a more "relaxed" riding position. Some questions: Is there a name for this kind of modification? I'm just calling it a "bent seat post", but I might have better luck Googling if I knew what this was called. Is it safe to cut handlebars for this kind of seat post? A local mechanic told me they wouldn't support a person's weight, but some of the examples below appear to be modified handlebars. Is there some other material I can use? Someone suggested water piping, and I'm looking for more alternatives. Can a seat post like this be purchased? I'm guessing no, but you never know. Some examples via Google: subtle bend welded joint <Q> After some more searching, it looks like I'm looking for a layback seatpost , and they're available for purchase on eBay. <A> Without knowing your height or more importantly, your weight, recommendations can't be made, but I'll include links that may help you decide. <S> I surely wouldn't recommend making your own from handle bars or any material you don't know the history of. <S> If the seat post should happen to break off at the wrong moment, (I don't know of any good time for that to happen!) <S> , serious injury could follow. <S> Find a seat post meant for and designed for moving the seat rearward. <S> http://www.chubbyscruisers.com/shop/bent-seat-post http://search.aol.com/aol/search?q=backward-curved+seat+post+for+bicycles&s_it=spelling&v_t=keyword_rollover <A> I only weigh 155 pounds and my riding was slow and smooth as it is mostly on ice. <S> I have since replace the handlebar seat post with a real layback I found in a junk shop. <S> I only replaced it as it fit, looked better and was cheap. <S> Never even thought about the handlebar breaking, which now seems so obvious <S> I wonder how I missed it.
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I used an old chromo handlebar section to make a layback seat post and used it for one winter of riding without problems. There are seat posts available that have a curve that can be used to the rear or to the front.
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How to shoulder a bike? In a previous question it was explained to me that no cables pass under the top tube of my Specialized Hardrock, so that the bike is easy to shoulder. Well, it isn't. The top tube is quite thin (V-shaped) and the only way I can pull this off for more than a couple of minutes is to place the bike exactly over the shoulder strap of my backpack. But maybe I am doing it wrong. How to shoulder an MTB? Should the bike be parallel to the ground or vertical, or tilted? Are there some bike designs that are aimed to be carried (besides all light bikes) - maybe the cyclo-cross bikes? Are there any suitable preparations before leaving to a journey in the high mountains, where one will be passing very difficult terrain with the bike on the back?* Very difficult for someone carrying a bulky bicycle and a backpack with food, at least. Summer weather, maybe muddy. About 2000 meters height. Crags and plenty of options to trip and fall. <Q> I ride a lot of trails where it is almost impossible to ride up and sometimes not even practical to push the bike up, and it is easier to carry. <S> I've got a full suspension mountain bike with no space inside of the triangle, so it is not possible to shoulder it. <S> And carry a bike on my back, rather than on a shoulder. <S> Bottom tube is resting on my shoulders with rear wheel on right from my head and front wheel on left from my head. <S> Like that: It helps if you have a backpack, as the bottom tube rests on it. <S> After some practice you can have both of your hands free, while bike comfortably sits on pack. <S> This way bike does not get in your way and you can hike quite a big distances. <S> UPD: <S> This position is not the quickest to put the bike up, but I find it the most comfortable when climbing. <S> To get the bike up, stand on non-chain side of a bike, place left pedal (closes to you) in the lowest position, grab with one hand the left crank and fork stantion with the other hand. <S> Lift the bike over your head and on your shoulder/backpack. <A> The slope of the top tube plays a big part in how well it carries. <S> The greater the slope the smaller the triangle and the more difficult <S> it is to get your arm between the frame. <S> If you notice cyclocross frames have a near horizontal top tube. <S> Shouldering the bike is an established part of the race. <S> Looking at images of Hardrocks the toptube has a decent slope <S> so my guess is it will never be comfortable to carry. <S> You could try rigging a shoulder strap from the saddle to the stem. <S> You will still have to deal with the nose of the saddle hitting you in the back. <A> which is what seems to cause the most discomfort) <S> Additionally, make sure the top tube rests on the top of your muscle, not actually on your shoulder itself. <S> Muscles cope easily with a metal weight - bones not so much. <S> Finally, I always tilt mine down slightly to the front, this way I can get the tube to sit really nicely on my muscle without the pedal bashing me in the back. <A> Statistics of pushing mountin bike at a steep ascent/descent or/and very difficult terrain: Activity time-before-tired stability time-to-switch speed-of-travel clearance <S> 1st-hand 2ns-hand------------------------------------------------------------------------------------------------------------------------Ride <S> * <S> * <S> ** <S> ***** <S> * handlebars <S> handlebarsPush <S> **** <S> ** <S> ***** <S> * <S> * handlebars handlebarsLean <S> ***** <S> ** <S> **** <S> * <S> * handlebars stemSafe-push <S> *** <S> *** <S> **** <S> * <S> * handlebars <S> seat-tubeLow-carry <S> ** <S> **** <S> *** <S> ** <S> ** handlebars seat-tubeMedium-carry <S> **** <S> **** <S> ** <S> ** <S> *** free down-tubeShoulder-carry <S> *** <S> ** <S> * <S> ** <S> *** <S> free down-tubeHigh-carry <S> * <S> ** <S> * <S> *** <S> ***** fork seat-stay <S> Notes <S> : Always strive to hold the bike near the center of gravity. <S> Holding the bike at the handlebars has the aim of controlling at lest one of the brakes. <S> The stability characteristic is important only on dangerous terrain. <S> For example, if the bike hits a hidden bump and swing at you, pushing you at a void to you death, this is important. <S> The "time-to-switch" characteristic indicates the time to go to the position of holding your bike, ready to mount. <S> This is important when the terrain is widely unknown and switching between riding/pushing/carrying happens very often. <S> Have fun!
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When shouldering any bike, I always have my hand up next to my shoulder so it actually takes a large part of the weight, and it is key to stopping the bike bumping up and down on my shoulder ( There are some designs that shoulder better than others.
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Clicking noise from crankset A month ago I bought a Scott Aspect 60, and for about a week everything was ok. Then, I started hearing a noise coming from the crankset. First thought was that it was the front derailleur - after adjusting, the noise is still here. Next, I tried cleaning the chain and lubricating it - didn't help with the noise. The noise happens regardless how I pedal - sitting on the bike, standing, on a stand, forward, reverse. If it means anything, the noise is gone if I remove the chain. The noise is more-less constant, something like clicking, but irregular, perhaps more like scraping, but I checked, the chain doesn't touch anything other than the chainring. Is there anything else I can do on my own? <Q> You may need basic tools for most of the following, but if I were you I would check these components in this order: <S> Your rear quick release. <S> If this is too loose it can creak or click. <S> This is especially true for newer external cam (aka exposed cam ) <S> quick releases. <S> This is the case more than you would expect and requires no tools to fix. <S> For the external cam QR type you might want to put a couple drops of lube on the moving parts to reduce friction. <S> If it's an internal cam type QR, just make sure it's tight. <S> Your crank arms. <S> If they are especially loose you can ruin them or they can fall off while you're riding (but this is also true for any part), so make sure they're tight. <S> Your pedals. <S> Sometimes even when properly tensioned you will get a minor click from pedals. <S> Make sure <S> they're well greased and tightened to spec. <S> Your chainring bolts. <S> Same deal. <S> Make sure they're tight and greased or loc-tighted. <S> There are other potential issues but the ones listed above are the most likely culprits that are most closely related to the drivetrain. <A> There is no better place to turn when faced with a creak, click or clunk than Sheldon Brown . <S> Does the creaking only occur when you are pedalling on the bike, or can you recreate by lifting the back wheel and pedalling with your hand? <S> Creaking under load is often simply a bottom bracket that has not been fully tightened. <S> As the bike is new and it uses a cartridge bb <S> this could be likely so I'd check JM2's suggestions and if none of those work then take it back to the shop where you purchased it and explain the sound to them, they should be able to identify and rectify it relatively quickly (a bottom bracket requires a special tool). <A> I experienced the same condition of having a "clicking" noise that seemed to be coming from the bottom bracket/crank arm area. <S> I too always keep my chain clean an lubed. <S> Removing the chain and turning the crank arms quieted the clicking noise. <S> I inspected the chain and determined that there was a suspect link or two in the same spot. <S> An easier fix than if it had been the bottom bracket or a chain arm that was the problem. <S> You may want to try the same type of repair.
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If they are not properly tightened or greased, they can also make noise. I bought a new chain, cleaned and lubed it, installed it and the clicking noise was gone.
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Cause of spalled cones? Was getting a sort of rubbing sound from my front wheel, like rubbing brakes, but the sound continued even with the bridal loose. So I disassembled my front hub. Everything looked good until I got to the cones. One has a rather noticeable line worn by the balls (more so than I've seen on other bearings), and the other has what I would call a spalled spot in addition to the line, with a rough, wavy area for maybe 15 degrees of arc. The cups, on the other hand, look factory fresh. This is a Shimano RSX hub. Any idea what would cause this? The hub has 25-30K miles on it, but has been overhauled twice. The sound came up over a period of maybe 100-200 miles riding. I don't go off-road and I don't jump curbs. Anyway, since the cups look good and the rim probably still has another 10-20K of life left, I'm thinking of getting a new hub and just swapping the cones, vs replacing the hub or buying a new wheel. Any reason not to do this? More info : I took a closer look at the cones. One is not really that worn -- there's just a barely-perceptible mark from the balls, and I'd not suspect it at all if it weren't for the other cone. The other is spalled to one degree or another all around, however. And, oddly, the two cones are not identical. The "good" one has the plastic seal washers, while the "bad" one has no groove for seal washers. Clearly, one or the other (probably the "bad" one) has been replaced in one of the two bike shop overhalls. So the question is, why was the old cone replaced? Presumably it was spalled as well, so what could be causing one cone to spall? I haven't removed the dust caps, so I can't get a REAL good look at the cups, but will have a shot at it again, using a flashlight. But on my several inspections so far the cups look smooth and shiny. And I'm certain the balls were replaced the last time around. (Unfortunately, inspecting 18 tiny ball bearings is just about impossible.) Here are pictures: Unfortunately, my camera only does a middling job with macro photography. In the first shot the bad cone is on the left and the good (stock Shimano) one is on the right. The second shot is the bad cone removed from the axle. The line you can see, up close, looks kind of like a bead of weld, with "puddling" -- little dents kind of pushed up against each other. When I went to remove the cone I discovered that it was very difficult to remove. Something had snarled the threads on the axle, at about the junction point between the cone and the lock nut. It was impossible to say with any certainty, but it looked like the axle was very slightly bent at that point. It may be that a bent axle was the cause of the failure (though I don't know how it would have gotten bent, or how a bend at that point could cause a bearing failure). Anyway, swapped in the axle from a new hub (also replaced the balls and repacked it) and the noise seems to be gone (though hard to tell for sure, as it was so windy for my test ride). Grrr!!! The noise is back, with the new axle, cones, and balls. Have not taken it apart yet, but I'm guessing one of the cones will be pitted when I do. And looking for a new wheel, I can't find anything on the internet. It's a Shimano HB-A410 hub, Mavic 622x18 rims, 36 hole. So far I've not found any 36-hole front wheels, and most of the 622 road wheels I find are "aero" -- not exactly the style for my touring bike. I'll check the local shops to see what they can get -- failing that I suppose I'll have to build my own. "Final answer": Pretty much convinced that the hub was bent and came that way from the factory. This is consistent with the repeated spalling and the damage to the axle that I found. Replaced with a nearly identical wheel from Peter White and things seem fine. <Q> Time traveling here... <S> If that type of spalling occurs after several thousand miles, then that's most likely normal wear from the little bit of play vs road vibration, etc. <S> If that occurs within 200 miles, then it means your cone nuts are too tight. <S> Some people here say there should be no play, but that is incorrect. <S> There should be a tiny bit of play in the axle/bearings. <S> If you smack the axle, you should hear it tap lightly. <S> If you have it too tight, you'll feel very little or zero play, but when you twist the axle by hand, you will feel it grab or catch very slightly. <S> Or, if you hold it by the axle ends and spin the wheel <S> , you'll see it grab periodically <S> (change in friction makes it twist a little in your hands). <S> That is the minor imperfections in the races and the bearings fighting each other. <S> There should be just a tiny bit more space than the largest imperfection combinations (for a micron or two of grease). <S> That means, most of the spacing will have just a tiny bit of play. <S> I find that every hub is a little different, but it usually takes 5-10 tweaks to get just the right amount of play when reassembling the wheel bearings/axle/cones/locknuts. <A> Play allows sideways movement, which acts like a hammer on the ball bearings as the hub vibrates from being ridden, or hitting bumps on the road. <S> The other side is normal, with the bearing track. <S> If anything, the extra large compression track in that cone may be why there was a bit of play. <S> If there is no pitting in the bearing races, replace the cones, readjust the hub, and carry on. <S> Plan to overhaul and readjust the hubs 500-1000 km of riding after you replace the cones, because the will wear in a bearing track again on the new cones, and the hub will become very slightly loose because of it. <S> It may take 2 or 3 repetitions of this to settle in completely. <A> I don't wish to be rude but <S> how heavy are you? <S> Back in the 1950s my father owned an Autocycle (that's a heavy duty bicycle with a 98cc or a 50 cc engine) <S> The cups and cones were always giving trouble and he blamed this on the extra weight caused by the engine. <S> I would suspect that flaking or spalling of the race-ways might be due the lack of preload. <S> Ideally several balls need to be carrying the load at the same time. <A> Be certain to check on the quality of the grease...... <S> Automobile rear end (differential) lube contains a good percentage of zinc dialkyldithiophosphate--the this lube splashes along the rear axle (rear wheel drive vehicles) and is the only source of lubrication for the rear axle timken tapered roller bearings. <S> It is not unheard of for these bearings to last for over 150,000 miles. <S> Motor oil, especially racing oils, used high amounts of zinc d in the recent past. <S> (one of its primary functions is to allow metals to slide along each other and to slide along each other, in the absence of an oil film, with none to minimal metal destruction. <S> Zinc has been reduced, as it is destructive to catalytic converters. <S> So, to live with less zinc, most manufacturers have switched to roller cam tappets--as there is less friction than flat tappets. <S> (Flat tappets are probably the highest potential wear point (metal destruction) on an internal combustion engine. <S> Use bearing grease with zinc..... <S> and if you aren't certain--use just a few drops on each cone (after you pack in the usual amount of grease) and your cone life will be extended. <S> Be certain to adjust the bearings properly1 <S> ) turn them in--just barely finger tight2) rotate the wheel on the axle--it probably won't feel smooth and there will probably be a bit of resistance3) back off just slightly on the cone nut until the wheel seems free on the axle4) then back off <S> (turn left) <S> the tiniest bit of a turn5) then lock down both hex nuts6) check to see that the tiniest bit of slack can be detected--that's what you want.... <S> and I do mean tiny..... <S> and I do mean some
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This kind of pitting on the hub cone is usually because there was some small amount of play in the hub. Extreme Pressure grease might also help, not just thin oil. In the oil additive aisle of your auto parts store, look for crankcase additives containing zinc d. Rislone (zinc supplement( is a good brand--this stuff is made specifically for hot-rodders using much higher valve spring pressure on high lift camshafts--regular oil simply isn't going to allow that engine to last--unless it has a higher zinc level.
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Rolling backwards while pedaling forward on a Freecoaster Can anyone tell me what happens when rolling backwards while pedaling forwardon a freecoaster bike? I mean does it gradually slow it down, or does it cometo an abrupt hault? I have not tried it yet. <Q> I think there is some confusion about the difference between a Freecoaster hub, a Freewheeling hub, and a Coaster brake hub. <S> So briefly: <S> A freewheel hub is by far the most abundant and utilized piece of bicycling technology and relies on a ratchet and pawl mechanism (or similar) to engage the drivetrain while pedaling forward, but allows coasting when not pedaling. <S> Any freewheel or cassette hub uses this technology. <S> A coaster brake is a type of brake that is built into the hub shell that turns backward pedal force into braking force. <S> A Freecoaster hub uses a clutch mechanism to engage the hub shell while pedaling forward, but disengages the hub while pedaling or coasting backward. <S> This allows you to coast backwards without having to move your pedals. <S> They are totally silent because there are no pawls! <S> Above is a hastily drawn sketch of a freecoaster hub. <S> There are no pawls... <S> instead is a cone shaped clutch which is threaded onto the driver body which extends over the axle. <S> The driver cog on the left is supported on the axle by bearings on either side (there are also lots of other bits and pieces, but these are the general parts.) <S> When pedaled forward the driver threads through the clutch and pulls it into the wedged surface of the hub. <S> The friction between the hub and the clutch is what drives you forward. <S> When you change directions (or pedal backwards) <S> the driver threads the clutch to a backstop which adjusts the play from freecoasting to pedaling forward. <S> -- As @Daniel R Hicks pointed out, this is pretty much the same mechanism that a coaster brake utilizes except in reverse. <S> Pedaling forward ought to engage the clutch and slow you down. <S> -- <S> However...I'm <S> not sure that I recommend that you do this because neither the clutch surface nor the hub shell are designed for slowing, only for engaging. <S> (If anybody has more info on the actual construction of the hub shell...whether there is a steel insert to bear against and provide braking support, or whether the driver and hub shell are forward motion only, please edit away.) <S> Here is a fantastic video about freecoaster anatomy. <A> The short answer: You will probably fall on your back, so it's not a good idea to try doing this on high speed fackies. <S> The long answer: As answered before me, you stop. <S> That's why most of BMX freecoasters have quite big angle of free crank turn (and it's even adjustiable in some models, like the KHE feecoaster ), so when you land in fackie (for example from 180 from stairs) even if you go a bit forwards on the pedals (and it's quite reasonable <S> you'll do it), you still be able to roll back. <S> Otherwise you would be flying on your back (same thing like when you lock your front brake). <S> Note, this way you can't do lots of tricks that are meant to do with tailtap (360 with taps, brakeless tailtap and so on). <A> If you do that while going backwards that means that your front end will most likely want to rise. <S> In BMX this is usually accompanied by a 180 degrees movement of the body so the bike turns <S> and and you continue forward with the momentum you already had going backwards. <S> Note that a freecoaster may have been set in such a way that it has some degrees of slack (a dead period) between pedaling and the moment the freecoaster engages. <S> This, for example, can be set to 60 degrees (1/6 of full circle) or even more if you are into bmx flatland riding . <S> The reason is that on some tricks you need to be on the pedals going backwards (possibly only on the rear wheel only) <S> so you really wouldn't want an accidental engage of the freecoaster due to your foot minor movements while trying to balance.
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If you were to pedal forwards while coasting backwards, your pedal force would engage the clutch into the hub shell. As soon as the freecoaster engages it will come to an abrupt hault.
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Which tires should I buy for an old road bike? I am upgrading an old road bike, which has Reynolds 531 tubing. (just to date it for you!)I know the wheel dimensions: 700 x 28c, and have found several sets of tires, but am unsure which to choose. The bike will be used as a road bike, if that helps? http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_249652_langId_-1_categoryId_242553 http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_811429_langId_-1_categoryId_242553 Any help much appreciated! <Q> It depends on how you intend to use the bike. <S> If you're intending to race, you'll probably want something lightweight and very grippy. <S> If you're commuting or touring you should tend towards the durable end of the tire spectrum With a nice steel frame like that you'll get lots of comfort, so it seems to "fit" with putting wider, comfortable, durable tires on it. <S> The two you've listed don't have a great reputation for durability, so it may be worth investing a little more for something that will last longer and save you the frustration of punctures. <S> Consider Continental Gatorskins or Schwalbe Marathons. <S> Both are more expensive, but offer good puncture protection which, in the long run, shortens your journey time more than a few grams of weight saving. <A> Kevlar belted tires are the way to go. <S> YMMV <S> but I find that almost-slick road tires with asymmetric channels provide the best interface with both wet & dry pavement. <S> Also consider that slicker tires roll more easily <S> not because they are smooth but because they have significantly larger contact patches then say 'nubby' mountain bike tires. <S> If you plan on traveling any amount of distance with any frequency you may want to look into a tire that will not require a significant energy investment. <S> or you could just soldier thru and build those legs! <A> The best advice will vary from one knowledgeable person to another but it will almost always matter if your main criteria is comfort, handling, rolling resistance, durability or puncture resistance. <S> And, of course, price. <S> If you look on Schwalbe's web site you'll see that they give a rating for each criteria for every tire. <S> When you want to maximize several criteria you'll wind up with something like their Marathon Supreme tires for about $75 each. <S> Even then they are not their "fast" tires. <S> Also note that Sheldon Brown and others have written/proven that, on bicycles at least, tread does not affect handling on wet pavement. <S> There just is not enough of a contact patch to cause hydroplaning. <S> And regarding Kevlar beads, one advantage they do have it that they can be folded up to more easily be carried as a spare.
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A wider tire is more comfortable with the only disadvantage being that it is a bit heavier. If the bike originally had 28mm tires, I would expect it to take 25-35mm with no problem, but check the rims for any other indication.
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Replacing 42/52 crankset to 39/52 - will it make a difference? I have several questions that arise from the fact that the current drivetrain on my old Peugeot road bike is pretty tough to ride when climbing up some steep hills: so I've got a 42/52 up front and 6 speeds (largest: 24) on the back. So my first question: will changing the front to e.g. 39/52 setup make a noticable difference. If so, can it be exchanged to e.g. some older/used crakset such as this Campa http://apro.bikemag.hu/files/4/2/listing_photo159024_555485241366650384.jpg It has the same tapered square connection as the current one. <Q> You asked: will changing the front to e.g. 39/52 setup make a noticable difference?My answer is an unequivocal 'yes'. <S> If you can however, consider 34 or 36-tooth inner and 50T outer, if you can find chainrings that fit your spider. <S> TA make a large range of chainrings, however new ones will probably cost more than the monetary value of your bike. <A> You will definitely notice the changes. <S> I have found this online calculator to be the best of a kind: http://gear-calculator.com/ <S> Just enter your gear combinations (for cogs use custom and drag 6 of them in rigth places) and wheel size. <S> For cadence use values 60-120 (these are "comfortable" values for short periods, "normal" would be around 90) to see the speed you can get with each gear combo. <S> There is also an option to compare two configurations, use your current config as a reference <A> Usually easier to change rear cassette (or wheel) than the crank. <A> Gearing is a function of the ratio between the chain rings on the front and your cassette on the rear wheel. <S> Check out WTHarper's link to Sheldon Brown's gear calculator. <S> FWIW, I have an old Motobecane with similar gearing. <S> Trying bikes with a slightly different gear ratio didn't seem to make enough of a difference on extreme hills (like in San Francisco) to significantly improve my ride.
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If you are really cheap, a fleamarket wheel might be the ticket, just check tor trueness and tight spokes.
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Should thighs touch the stomach to reduce flab? I got myself a new bike and i have been told by many to reduce the seat height or bend more to cycle such that the thighs touch your stomach or atleast closer to stomach as you cycle. They say it will reduce the flab quickly and better workout. Is this true? <Q> I think that this is a bad advice you've heard (by many?). <S> For pedaling seated, the seat has only one position; the proper one. <S> See <S> How do I determine the correct position for my bicycle seat? <S> for info on how to set it correctly. <S> Regarding the flab thing, as far as I know touching your stomach with your thighs (or any other part of your body) will not contribute to a better workout or a six pack. <S> For that I guess you'll need lots of proper training and a consistently proper diet. <A> As others have said, what you're specifically suggesting sounds bad. <S> Your seat will have a correct height, dependent on the geometry of your frame and the length of your legs. <S> Period. <S> But I can add something regarding fighting flab. <S> I was around 105kg back in 2008, I've been about 75kg for the last couple of years. <S> I have lost that weight purely through cycling. <S> As you might expect my legs have become extremely muscular. <S> As regards my upper body though, I've not become amazingly muscular because I don't really work those muscles, however I have benefitted just by losing weight "all round" (for example, I still look down and see a gut, but <S> t-shirt sizes used to start with X, now I'm a S/M, so something good has happened). <S> You will lose weight, but it will take time. <S> To accelerate this, I can think of two things, (i) <S> more miles (especially as your body becomes more able to cope), and (ii) <S> your diet. <S> If you're specifically wanting to tone your upper body, I'd suggest doing some supplementary exercise, but cycling should give you all the lower-body and cardio you'll need. <S> Lastly, good luck. <S> Obviously it is very much in your own hands, but know that it is possible to get rid of that flab. <A> To ignore what may be a bad idea in terms of bicycle posture and address what seems to be central to your question, which is the reduction of flab, you need to know this about flab: <S> You cannot spot-reduce . <S> With the exception of liposuction. <S> Your DNA determines where your fat ends up. <S> You know how some ladies have normal upper bodies but have very large behinds? <S> Yeah, you do. <S> It's not because they're only active with their upper-half. <S> If you have flab and then develop very strong abdomen muscles, you will have an awesome six-pack covered by flab. <S> If you want the six-pack to show through, you have to lose the fat. <S> Muscle tissue does not transform itself into fat tissue nor vice-versa. <S> @Carey Gregory already answered this as a comment <S> but here it is as an answer. <S> I'd recommend the excellent <S> Why We Get Fat by Gary Taubes. <S> Adiposity explained. <A> Losing flab is a matter of eating less calories than you use on a daily basis. <S> There is some debate about the 3500 calories = 1 lb of fat equation, but many studies have shown that it isn't Paleo, South Beach or (insert diet fad X here), but simple calorie reduction over time. <S> If you want to seriously lose the weight, then I would find a calorie calculator to get your basal metabolism, which will tell you how many calories you need to breathe in and out all day. <S> Then add in the calories for all your activities, work, yard work, housework, play, etc. <S> Then start using a food tracker such as myfitnesspal, and let the scale be your guide. <S> Bouncing your knees off your stomach won't do a thing for flab except give you a sore stomach.
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The only way to reduce flab in one area of the body is to lose fat period. I guess what I am trying to say is this: set your bike up properly such that it is comfortable to ride, and keep putting the miles in. Get it wrong and your knees will complain.
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Why the wobbly/loose cassette? Why is my used Ultegra 10-sp cassette wobbly to the touch on a new Ambrosio hub? All spacers present/correct and 11-sprocket well-seated before torquing 40nM lockring. I tried another (used) 10-sp 11-21 cassette on the same hub and there is no wobble for that one. Puzzled! <Q> Note: Different cassettes may need different spacers. <S> Unless there is a defect in the cassette or freewheel, it should not wobble (at all!) <S> when properly installed. <S> Try removing and cleaning the cassette (a bit of dirt can cause it to get skewed a bit). <S> When you put the cassette back on, make sure there is about 1 mm of cassette sticking past the freewheel hub before putting on the locking ring. <S> Tightening a lock ring without the correct spacing can also easily strip the lock ring (which is better than stripping the threads in the freewheel, but will still ruin your afternoon). <S> If there is still ANY wobble, a visit to your LBS may be in order. <A> I ran into the same issue. <S> I installed a new SRAM cassette onto my newwheels and the cogs were loose. <S> After a few trial and errors, indexing gears, I realized I forgot to place the little black spacer first. <S> Then cassette goes on after. <S> It's those little steps that get looked over. <S> Cassette is solid as a rock. <S> Tight and shifting great! <A> There's a bearing that rachets between the cassette and the axle. <S> (I did it, that's how I know). <S> Bike mechanic can replace it ... they have the tools.
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If the cassette is not sticking past, then (just like a compression headset), you won't be able to tighten it properly and you will need to put additional spacers behind the cassette. If you are in a very low gear and crank hard up a hill, that bearing can get warped or crushed.
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Lights wiring polarity and wire marking I am re-wiring my bike lights to add a smartphone charger and improve the connections. Wires are going in pairs, one wire in a pair being marked with a white stripe. Since I am using LED lights, polarity is important. On electronics SE and in many places on the Internet I found that the white-marked wire should go to the plus. However, my hub dynamo has the marked wire connected to the contact marked with the ground symbol (so it is connected to the frame). Usually in electronics the ground is negative. Is it a mistake of the bike manufacturer or am I missing something? <Q> White stripe is ground. <S> Consistency is a virtue, and Schmidt's obvious decision tells us the industry default. <S> In principle, the two conductors are interchangeable, because AC. <S> However, in the reality of bicycles, there are practical considerations. <S> Some lights ground one side through the mounting screws and some don't. <S> Some bike frames are conductive and some aren't (and headset bearings are intermittent). <S> So it is important for all deliberate connections to have compatible ideas of what is ground. <S> Otherwise you have a short circuit. <S> When a mechanic replaces your dynamo or light with a unit that makes an assumption about what's grounded, the assumption better match your wiring. <A> No mistake - there is no standard. <S> 50% of the time the strip is -ve, 50% positive. <S> Get a multimeter - $10 for a cheapy, and remove any guess work......... <A> cheap dynamos create AC (which also works for LEDs) <S> you can test that easily by reversing the polarity of the LEDs and see if they light up in both orientations just add a diode (or diode bridge ) to the connection for the charger to go from AC to DC
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Some dynamos ground one side of the circuit through the axle and some don't.
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What is the logo gear worn by non-commuter cyclists? I live in the suburbs where there are many routes for road cyclists to go for rides. I assume these cyclists are riding for fun and/or exercise and/or to train for some kind racing events. Sometimes they are alone, other times they are in pairs or small groups. Many cyclists have big logos on their shorts and shirts. What are on the logos? Where do they get them? I don't see these in the online bike equipment stores. I can only guess that these are associated with professional racing. In any case, it seems that casual cycling folks don't have normal access to big-logo gear. Where would I get some? (I don't mean to sound judgemental, but I see it a lot but don't know where the gear comes from. I am curious about biking communities and what they wear. I am interested in hearing from those who wear such gear.) <Q> There are different types of logos which get worn for different reasons. <S> Bike clothing may include logos associated with: Clothing manufacturers: An otherwise plain jersey will often include the logo of the manufacturer. <S> This is common for athletic clothing in general. <S> Employers: Companies often make jerseys with their logos that (presumably satisfied) employees can wear to show spirit. <S> Sponsors of professional teams: Fans of professional cycling teams may choose to buy articles of clothing that are replicas of the official team uniforms. <S> These items include the logos of the companies that sponsor the pro team. <S> Local clubs or teams: A local cycling club may have their own un-sponsored logos. <S> Organizations can order custom kit in much the same way people order custom t-shirts or team bowling shirts. <S> These items may be offered at reduced prices or even for free to club members. <S> Races or organized rides: Some races and supported rides give or sell participants commemorative jerseys, which may serve as a memento or badge of honor. <S> Advocacy groups or messages: Cyclists may wear clothing to show support for a message or for an advocacy or non-profit group. <S> For example, jerseys may include designs featuring the "share the road" message. <S> Abstract design: <S> Jerseys and shorts may feature designs that are designed to just look good. <S> For example, one manufacturer sells jerseys featuring an imaginary team and based on professional kit from 50 years ago. <A> Generally, a matching top and bottom and sometimes a cap is referred to as a kit. <S> Why a kit? <S> I don't really know. <S> The top often has three pockets on the lower back for snacks/sunglasses/etc., a longer cut at the bottom to hide certain cracks when leaned over, and a higher cut on the front to prevent bunching. <S> The shorts or even bibs have what is called a chamois in the crotch which makes for a more comfy long distance ride. <S> Just like many other pro sports teams they allow for easy recognition. <S> The logos are often sponsors, the bigger the logo, the bigger the sponsor. <S> For example the US team sponsored by the USPS or Discovery Channel or Garmin. <S> The sponsor probably pays for a lot of the team expenses also. <S> Non-pro groups can order their own kits from a lot of manufacturers. <S> Groups could be a corporate affiliation, a bike shop for stock, a social group, etc. <S> Usually a minimum order is required, and the price drops as quantity goes up. <S> One could get sponsors to pony up some money for the order, partial or full, or make the group members pay for all costs. <S> Vendors usually provide a graphical template for laying out your design. <S> Pro fit may refer to slimmer sizing, where club fit may refer to more traditional sizing. <S> There may be other more common terms for these <S> but that is what I call them. <S> IMO, this brand makes some pretty cheesy but flashy jerseys and also accepts custom orders: http://www.primalwear.com/ <A> I would say that we're talking about something like this: <S> Looking online you have to search a bit to find a "classic" example, but on the road I see a lot of cyclists with such jerseys, sporting various brands, and <S> at least one nearby shop doesn't seem to carry anything else.
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Sponsors of local clubs or teams: A local cycling club may have team apparel that includes logos of the local bike shop and other local companies that sponsor the team.
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Can I carry my tandem on a bumper carrier? I would sometimes like to transport my tandem by car, and it would be convenient to use one of those "strap-on" bumper carriers. Is it feasible to use this type of carrier? <Q> If it sticks out from the width of the car DO NOT carry the bike in the bumper carrier. <S> If necessary, take both wheels out but take no chances, <S> anything wider than the car is a danger to yourself and others, think about motorbikes. <A> Yes, yes it is possible... <S> It's not totally clear in the following picture, but the horizontal bars are tilted up a bit to make it more secure. <S> It's necessary to bungee-cord the bike or otherwise secure it <S> otherwise it'll tend to slide "down" (in my case, the front will tip down, which will make it stick out on the driver's side). <S> I use 2 cords to secure it: <S> Other notes: <S> I immobilize the bars so that the wheel doesn't flop while loading/unloading (and while removing the front wheel, which I have to do to keep it from sticking out on the driver's side. <S> It's not clear in the picture, but behind our mini-van, the front forks don't stick out at all, and the rear wheel sticks out <S> maybe an inch beyond the width of the van. <S> Also, the bar-ends I have don't stick up above the roof box. <S> Although it looks ridiculous, the same technique can be used on a small car: <S> The bike doesn't actually stick out beyond the width of the car as much as it appears to in the picture, it's less than a foot on each side. <S> It does stick way way up above the car, however, so when I've done this (only a couple times) <S> I'm very careful about going into underground parking. <A> Can you tow a trailer with your car? <S> That would be the safest and most responsible way to move your tandem. <S> Second option would be to ride it there, over the course of a day with rest stops you and your co-rider could do 100 km. <S> Another option would be a roof rack, like others have mentioned. <S> Your vehicle's roof looks long enough to accept the full length of the bike. <S> Brands to search for may incluide Thule. <S> Possibly you're looking for three cross bars, and two normal "bike rails" in line-astern or as close to that as possible. <S> May have issues with the front bottom bracket being super low, which means an adapter to raise the front fork a bit more than normal. <S> Please let us know what you end up doing.
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If the tandem is loaded onto the carrier at an angle, it won't extend much beyond the width of the car or minivan (maybe not at all for a larger vehicle).
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Pain in left hand I'm a relatively new cyclist (started about 4 months ago). Lately, I've noticed that I have numbness and tension/pain in my left hand (but not my right one) throughout my ride. Every 15-20 minutes or so I have to take my left hand off the bike and stretch my fingers a bit. I feel like there is some kind of imbalance in the way I ride, but I can't pinpoint what it is or how to correct it. Can anyone suggest things I can do to try to fix this? In case it's relevant, here's some random info on my riding. I'm not doing super-long distances or anything -- I ride about 10 miles 4 days a week and maybe 30 miles once a week (and this is near Houston, so there are no hills). I've been riding a Specialized Secteur Sport which was fitted for me at my LBS (though this was not a very intense fitting -- it took maybe 15-20 minutes). <Q> Based on your comment about where your pain centers, it sounds as though your median nerve is acting up. <S> The likeliest causes of this for a cyclist are leaning too hard on the slight depression in the middle of the base of your palm, OR a hand position that twists your hands (inward/outward and/or up/down) relative to your wrists. <S> Check for these next time you ride. <S> Do see a doctor if you can (you may have to be firm about being referred to a physical therapist or sports-medicine expert). <S> It's easiest to deal with this soon after it is noticed, certainly before it is debilitating. <S> (Which it can be. <S> My non-cycling-caused ulnar neuropathy had me holding my hand against myself <S> so no one would so much as touch it, and it took six solid months of punishing therapeutic massage -- don't be fooled; physical-therapy massage is NOT gentle or enjoyable! -- to rid me of it.) <S> Varying <S> your hand positions may help avoid the problem in future; I would recommend ESPECIALLY avoiding the brake hoods, as they can hit RIGHT where you don't want them to. <S> Your bicycle has drop bars, so you can experiment. <S> I have found that my Velo Orange trekking bars somehow manage to avoid ever letting me rest my hand on that central depression, and allow at least two neutral hand-wrist positions, so changing bars might also help you. <S> Why left hand rather than right? <S> It may not be anything in your cycling, though you can certainly watch for something. <S> Our bodies aren't perfectly symmetrical, and general stress on them isn't either. <S> Good luck! <S> I hope you resolve this quickly and as painlessly as possible. <A> Check if the handle bars are centered. <S> Check if you are sitting properly centered on the saddle, slight lean can cause uneven distribution of weight at your hands. <S> Are you left handed and use computer mouse often? <S> Above mentioned are the things I would check. <S> In any case, don't neglect it. <A> Check your brakes, maybe they lack braking force <S> and you squeeze them way too hard <S> Adjust your riding position to the best practices (google it) <S> Get a nice pair of grips Same thing about riding gloves <S> If nothing helps - consult your physician. <A> I found something similar with the stock grips on my GT Traffic hybrid even with decent padding on the palms of my gloves. <S> I switched to something like these ergo grips with mini bar ends built in - <S> I think mine were the old version - and have had no issues since. <S> You do need to get the angle of both palm-pad and bar end right for you, and probably brakes as well. <S> I don't really use the bar ends on my commute - too far from the brakes given the riding conditions for much of the route - <S> so it's the grips that do it for me. <A> All answers given are ok with me, I only wanted to add, Softer grips can make a big difference and break bar position might be too high/low for you. <S> Don't wait too long to see that Doctor.
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If the saddle is too high and the handle bars are not positioned appropriately, you may be exerting a fair amount of weight on your hands. I would strongly recommend that you consult a doctor.
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Does the term "domestique" have negative connotations? As far as I understand, the cycling term "domestique" (referring to a supporting member of a professional cycling team) comes from the French word for "servant". According to Wikipedia, it was first used in cycling as an insult: "He is unworthy. He is no more than a domestique." Is the cycling term "domestique" still pejorative? What are its connotations in modern cycling? Do racers refer to themselves as domestiques, or would they prefer to be called something else? <Q> The word was first used in cycling as an insult for Maurice Brocco, known as Coco,[4] in 1911. <S> Brocco started six Tours de France between 1908 and 1914, finished none of them, although a stage he won in 1911 caused the coining of domestique. <S> -- <S> http://en.wikipedia.org/wiki/Domestique <S> In road racing, if you are young and unproven you often get your start as a "domestique" on a team. <S> You are the cycling equivalent of the chore boy. <S> The job of the domestique is to sacrifice his or herself for the leader and team. <S> If one of the stars an your team needs some food, you have slip out of the peloton, and go back to the support cars pick up the food, then work your way back up to and through the peloton to deliver the goods. <S> Likewise if you are in a situation where either the domestique or the star gets water, the star wins out. <S> If the team is worried about a break getting away, it will often fall to the domestique to set the pace and do all the work to close the gap. <S> Basically, the domestique is an expendable asset of the team. <S> Their final race ranking is of little to no concern, other than to remain in the race so that they can provide their services. <S> That said, as you prove yourself as a domestique ( <S> ability to ride hard and survive <S> ) you will be given more opportunities, eventually working your way up in the team. <S> If you are a fan of the sport, following the domestiques may give you an idea of who may be the upcoming stars. <A> Domestique is only really a term found in (professional) team cycling and in that context it isn't really pejorative <S> , it's descriptive of the role performed in the team by those riders without aspirations to overall honours, but who are there to support their team leaders and specialists. <S> While it stemmed from the French for 'servant' the term has evolved and softened. <S> On some stages roles might be reversed, perhaps on a rolling hilly stage the star sprinter without a chance of a stage win that day would turn to playing the domestique, e.g. in last year's Tour de France , the then reigning World Champion, Mark Cavendish, was seen at the team car stuffing bidons up his jersey and ferrying them back, often this will result in the description super-domestique , recognising the role change. <S> Where it might be pejorative is use away from the pro peloton. <S> If you're on a club run or a ride with friends and someone asked you to do something that you didn't want to do, "what am I, your domestique?" would be about right. <A> This may include such things as ferrying food/water from team cars, working to control the pace of the peloton, support a break, even down to giving the team leader their own bike if a mechanical failure happens at a critical point. <S> What makes it perjorative is the context in which it is used. <S> If someone uses it as a put down, then yes, it's demeaning. <S> If someone simply uses it as a description, then it is not. <S> Servant is a similar term. <S> Servants were NOT slaves. <S> They are people who serve others for a salary. <S> Many servants both in older times when it was more common and more modern times were/are fiercely loyal to the house they serve. <S> Especially in Europe where it is more common, head butlers and similar for peerage (Lords, Earls, Dukes, etc) were highly respected. <S> If a lord got a reputation for not being good to their servants, it was hard for them to get more. <S> But, you can use servant as a description or as a putdown.
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Domestique by itself is neither a good nor a bad term. To an extent, yes it does have negative connotations. It simply refers to riders on a team whose role is not to work for their own race ranking, but to perform the day to day tasks and support that enable the team leader to advance their own race ranking.
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Hydraulic disk brake stops working when hot; back to normal after cooling - is this expected? I have experienced a strange failure of my brake. I was descending a steep smooth road, using only my front brake (my rear brake was broken; it was an unplanned bail from a route). I tried keeping the speed low, so i could jump off the bike at any moment. After going this way for maybe 2 minutes, I stopped briefly to let some car pass (so released the brake for a few seconds). As I continued to descend, I pressed the brake, and surprisingly, its handle went all the way to the handlebar without doing any braking! So I immediately jumped off. I didn't believe at first the bad luck I had, but then I pressed again and again on the brake (not while riding now), and gradually it returned to normal; after 1 minute it would give full braking force again. So I wonder, is this an expected way a brake would fail while overheating? I heard that it would start to stink really bad before it became dangerous to ride, so I didn't worry about overheating. The model of my brake is Hayes Nine . <Q> The least you need to do is bleed the brakes to remove trapped air. <S> It's best though if you completelly change the fluids and bleed. <S> You can do that in an LBS, or yourself if you have a bleeding kit and know how to do it. <S> The reason for the behavior you described is that air is trapped in the system and makes things mushy and unpredictable. <S> The fact that after a couple of lever presses it came back to "normal" is because hydraulic brakes are auto adjusting both on the pads end <S> (when pads are worn) and on the lever end (when air is in the system). <S> Air bubbles exist in the system either because a proper bleed was not done in the first place or because the fluids absorbed moisture which vapourated and turned into air as soon as you overheated the fluids. <S> Also note that as soon as the fluids absorb moisture (water) then the boiling point falls even more so having this issue is even easier. <A> All brakes work by converting kinetic energy into heat through friction. <S> In disk brakes, the heat builds up in both the rotors and calipers. <S> Under heavy sustained braking, such as down a long steep hill, the calipers can get hot enough to start to boil the brake fluid. <S> This is called brake fade . <S> The good news. <S> This will go away as soon as the brakes are allowed to cool down, and only happens on sustained heavy braking. <S> 2 minutes constantly engaged is certainly a very long time to brake. <S> The bad new. <S> This can only be avoided by using an individual brake less. <S> On long downhills, switching between front and rear will allow each brake to cool in turn, and stop brake fade. <S> If the brakes do use something like DOT4 brake fluid (usually not for bicycles) <S> the fluid will eventually wear out, and fade badly. <S> This happens when water gets into the fluid, lowering the boiling point. <S> Flushing the brakes with new fluid will help if the fluid has degraded. <S> This is true for all hydraulically activated brakes, on any vehicle anywhere. <A> Just to expand the answer for future reference. <S> Sram have a good explanation of this: Vapor fade is caused when brake fluid boils inside the brake caliper and hose. <S> Boiling is where a drop in fluid pressure (which occurswhen a fluid is heated) allows microscopic pockets of gas suspended in the fluid (bubbles) to expand, creating larger bubbles. <S> Fluidsunder significant pressure require much higher temperatures to boil than less pressurized fluids. <S> This means that the fluid can actuallyreach temperatures above its normal boiling point during hard braking (high pressure). <S> However, as soon as the lever is released, thepressure immediately drops. <S> With the fluid temperature still above its normal boiling point, this sudden loss of pressure causes thefluid to instantly boil, creating large bubbles in the brake system. <S> With large bubbles now present in the system, pulling on the brakelever compresses the bubbles in addition to moving fluid, allowing the lever to bottom out against the handlebar before enough fluidpressure can be generated to actuate the slave pistons properly. <S> This results in a loss of braking power. <S> And add this: A brake system that has undergone vapor fade should be completely bled before riding again. <S> Boiling brake fluid will cause abreakdown of the fluid composition and can exhibit lower boiling points in future brake applications. <S> Reference Hydraulic Disc Brakes Overview
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Because gases are easily compressible, boiling brake fluid causes a loss of braking ability.
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what type of bike/frame to use when overweight? I'm around 230lbs. Since I do enjoy biking, I was looking up old school racing bikes on craigslist. Some of the frames are built with "Tange 1" steel which specify weight limits (180lbs). Is it really possible that I might damage the bike if I choose to ride it? For someone my weight or higher, what kind of bike and/or frame should be used? Is there any concern if an aluminum frame is used? Or does all of this depend on the manufacturing quality (eg, Tange 1 instead of Tange 5)? <Q> Old-school racing bikes (I have two) are not as comfortable as old-school MTBs when you resume riding, especially if you have a bit of a gut. <S> The upright riding position that the vintage MTBs offer (or a modern equivalent) is one of those things that can keep you on the bike until riding a road bike becomes more comfortable. <S> When I resumed riding (as a middle-aged adult), I was fortunate to get this at a local garage sale for $20: <S> With the benefit of hindsight, I can tell you that had I resumed riding on an old-school racing bike, I would have certainly quit. <S> I was way out of shape, and the bent-over position required for riding a road bike would have been so uncomfortable that there is no way I would have persevered. <S> But this Peugeot was just what the doctor ordered, no pun intended. <S> I rode it for about 1,400 miles (about 2,250 km) before upgrading to the old-school road bike. <S> Of course, YMMV, and you didn't mention your height or your age. <S> BTW, one of my old-school racing bikes has Tange #2 tubes and I am still around 200 lbs. <S> I put about 1,500 miles on that bike, for what it's worth. <S> Final thought: you may find this subforum helpful. <S> There are ( and have been ) <S> many folks in the same boat. <A> When I was racing seriously, I got down to 235 lbs, and am now closer to 275lbs. <S> I ride a Titanium Litespeed, and classic steel frame bikes. <S> (Have four bikes at the moment). <S> I.e. <S> Over years of riding regularly, I broke an old steel frame. <S> Replaced it with a similarly old same model frame, and finally just cracked a drop out. <S> Got that one welded, and moved on. <S> I have broken a couple of seats over the years. <S> I had borrowed my brother in laws Walmart style bike, and I bent the cheap steel seat post (when it was over-extended to make up for small frame size) and I was climbing hard, seated. <S> But that was an extreme example. <S> I bought a cheap replacement from a bike store, of greater quality than the cheapo bike deserved and it was fine. <A> I'm about your weight. <S> I've ridden an off-the-rack aluminum step-through (Electra Townie, specifically) and a custom steel tourer (also a step-through) and both have served me well. <S> (Step-through frames are not as intrinsically strong as diamond frames; I once read a cycling how-to book that utterly dismissed step-throughs on that sole basis. <S> Whatevs. <S> When that author rides to work in a dress on his diamond-frame bike, he can criticize my step-throughs.) <S> I can't speak to carbon fiber or titanium or exotic frame materials like bamboo, however. <S> Basically, I concur that you'll be fine. <S> Do also remember to loosen the clamp and move the seatpost every once in a while, so they don't end up forever stuck in place. <S> Potential bonus <S> : I have never, not even once , been street-hassled over my weight while on a bike. <S> (It's happened while I was a pedestrian, many a time.) <S> I cannot entirely explain this -- it may partly be my penchant for interesting-looking and extremely purple bikes -- but I'm not complaining! <A> I have a 2013 Trek X Cal and also a 2015 Trek Remedy 9 29er. <S> I'm 6'2", and when I started biking <S> about 8 months ago I weighed 321lbs, <S> now after over a 1000 miles of mountain biking I'm a trimmed down 255lbs. <S> I believe the Treks are also rated at 300 lbs <S> and I have had no problems with either bike. <S> I've also never felt that either frame or rims were being stressed because if my size, and both bikes still feel like race rockets to me, even on my large frame. <S> I've also ridden a couple Santa Cruz and and Kona bikes and they also feel like we'll built bikes to me as well; probably capable of handling larger riders as well. <S> I have heard from a couple people that the 29er wheels are better for larger people, but I don't really know for sure if that's true?
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The things where weight matter are usually pedals, since you apply a LOT of force to a fairly small piece of medal. While I have cracked my Ti frame (and gotten it welded) and broken some steel frames, it is a very rare thing. The only thing I'd warn you about based on my own experience is tightening your seatpost clamp; I've had seatposts decide to lower themselves, particularly after bumpy bits of trail.
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What are the most common causes for hysteresis in the rear derailler? I have often seen derailleurs on cheap MTBs to degrade in performance by showing hysteresis. By that I mean that to switch to a certain cog, one needs to shift one cog further and then immediately one back to get the chain to the desired cog. What could be the cause for such degradation of shifting quality. Is this often a tuning problem, or wear, or the derailleur spring getting stuck with dirt and grime? <Q> Here is the list of things I usually check for when troubleshooting jumping gears: <S> Is the chain always goes up/down? <S> In this case usually the adjustment is off. <S> Try adjust the cable. <S> Is the mech hanger bent? <S> Sometimes during a crash you can bend a mech hanger. <S> Most of the times you can bend it back, but there are cases where you need to replace the mech hanger for a new one. <S> Usually they are cheap £5-15. <S> Is the shifting very slow? <S> Dirty outer cables and rusty inner can cause the problem with shifting. <S> Replace inner cable and outer cable for new ones. <S> Is the shifter clicking OK? <S> I've seen cheap shifter wearing out and not "holding" clicks properly, so the chain would jump. <S> Are the mech cogs (small chainrings) <S> worn out? <S> are they wobbly? <S> Chain can only be placed properly if the cog is not moving sideways. <S> If that is the case, replace the top cog. <S> Also worn out cog can affect the shifting performance. <S> Is the mech itself not bent or otherwise damaged? <S> There are plenty of ways to destroy the mech.. <S> usually that is beyond repair <S> and you need to get a new one. <S> If the mech is very-very cheap, it sometimes gets bent while in normal use (not MTB abuse). <S> Only replacement will fix that. <S> Good luck! <S> And I'm off to fix my wife's bike gears -) <A> In most cases it will be a combination of several of the factors you describe. <S> It <S> can be a tuning problem. <S> In this case normally the gear change will work in one direction but not in the other one. <S> If it is only a tuning problem, it may be fixed quite easily by tuning your derailleur correctly. <S> Also for this type of problem it is characteristic that it can occur in both shifting directions depending on the "direction" of detuning. <S> Unfortunately especially on cheaper derailleurs tuning may not be the only problem. <S> The second one is friction either in the bearings <S> * of the derailleur or of the derailleur cable in the cable hosing or both. <S> In this case the problem is typically much worse in the direction where the the cable is released by the shifter and the spring does the work. <S> Normally the derailleur should jump to its desired position with one sudden step, but if friction comes into play it may creep more or less slowly to its position which might give the chain not enough momentum to jump to the right cog. <S> As cheaper derailleurs are built with simpler bearings they are more prone to such failure. <S> A maybe slightly too weak spring may worsen the situation here. <S> Another point that you didn't mention is the wear of the derailleur bearings. <S> The whole device consists of several linked parts that are aligned to each other to certain axes. <S> In this case the chain may run from the derailleur to the cogs in an angle that hampers the shifting process. <S> * <S> As pointed out in the comments there are no real bearings in the links between the parts. <S> Instead the links consist basically of two surfaces that glide on each other. <S> But there is a huge difference in the quality and durability of those surfaces and in how good they can withstand contamination that causes friction and wear. <A> Keep in mind that this was the norm for derailers, pre-indexing. <S> Indexing wasn't possible with the old style drivetrains because you needed to overshift slightly to force the chain to jump sprockets, especially when shifting to a larger sprocket. <S> What changed was mainly the addition of what I call "ramps" on the sides of the sprockets. <S> These catch the pins of the chain and lift it up onto the higher sprocket. <S> Without this feature indexed shifting would be impossible. <S> Thus, wear of either the chain pins or the "ramps" will cause poor shifting. <S> Of course, there are also the other possible causes that Benedikt describes as well.
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If the bearings in the links are worn out in a way that there's some clearance, the derailleur may bend a bit, changing the alignment of the derailleur in respect of the frame and the cassette.
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Why are the rear wheels of time trial bikes disc shaped rather than having spokes? Won't having disk shaped wheels cause more wind resistance with crosswinds? What are the benefits of having these sort of wheels? <Q> Disc wheels have lower drag than spoke wheels. <S> See Wheelbuilder aerodynamic data and Aerodynamics of High Performance Race Bicycle Wheels . <S> (One link shows simulated data, the other measured). <S> Most of these tests run up to yaw angles of 30 degrees. <S> The argument is typically that at higher yaw angles (closer to side-winds) <S> the rider would choose a spoked wheel instead of a disc. <S> Disc wheels are typically preferred for courses and days that do not see a lot of cross-winds not because of drag, but because they present a large area for the wind to push on, and can lead to unpredictable performance in high-crosswinds. <S> This is one reason you don't often see disc front wheels in a non-velodrome environment. <A> I found a link here: http://www.wing-light.de/CFD/wheels.htm <S> but you can also get similar graphs from manufacturer. <S> It shows different amount of drag in different wind angle. <S> Crosswinds don't necessarily give high drag, obviously it should give lower drag than headwinds. <S> Even when it's directly blowing from the sides, depending on the speed of the bike and the wind, the resultant angle is not 90 degree. <S> Now, here's the interesting part, if you check the graph, at around 20 degree angle the disc actually has negative drag! <S> I reckon to get that kind of angle <S> , you need a higher degree angle (more like crosswinds) when you're moving fast. <A> Once hills (gravity and lower speeds) or changes of pace, come into the mix the case for spoked wheels becomes stronger. <A> I learned in physics class that solid wheels have a lower moment of inertia because the center of mass of the material is located closer to the hub (think of a skater holder her arms in and spinning). <S> Technically, this should make the wheel easier to accelerate and lower the resistance of spinning the wheel. <S> The do weigh more, so is this of any advantage and a reason for having them?
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The benefit of a disc wheel is that you can ride faster than with a spoked wheel, on flat and rolling roads and at steady speeds.
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Exertion time vs heart rate or %LT(Lactate Threshold)? Are there any tables out there that show how long a person can exert themselves at a given heart rate or %LT (assuming adequate fueling)? events lasting up to(LT = 185): 3 hours: 170+ 4 hours: 165 6 hours: 150 ??? IM: 130? <Q> Source - Metabolic Factors Limiting Performance in Marathon Runners (While the above paper is aimed at marathon runners, I'm not aware of any reason it can't be applied to other endurance sports such as long-distance cycling.) <S> Exercise is fuelled by a combination of fat (plasma free fatty acids plus muscle triglycerides) and carbohydrate (plasma glucose plus muscle glycogen). <S> The proportions used vary depending on the intensity of the exercise. <S> Exercise at a particular intensity can be maintained until you run out of carbohydrate - "hitting the wall" or "bonking". <S> Intensity is expressed as a % of VO2max, which can be estimated from heart rate . <S> In order to work out how much carbohydrate you have available, you need to estimate how much glycogen you can store in your leg muscles, how much glycogen you can store in your liver and how much carbohydrate you can take on as food (gels, sports drinks, etc) during exercise. <S> The methods section of the paper goes into this in detail. <S> In order to apply this practically to cycling you should take measurements of the power you can produce at various intensities (heart rates). <S> If you don't have the equipment to measure power, then measure speed on a flat course and estimate the power from that. <S> Having done all that you should be able to calculate the total energy required for a particular distance at a particular speed and what proportion of that energy will come from carbohydrate. <S> You also have an estimate of how much carbohydrate you have available and that will tell you if you're likely to hit the wall / bonk. <A> The short answer is "no", there are no charts or tables that can tell you this directly. <S> Recent training history (if you've trained a lot,you will have accumulated fatigue) <S> Recent stress history Recent health or sickness <S> Current mental state <S> For a given person at a given point in time, it is possible to determine what you are asking experimentally; for example, a runner can, over time, figure out their speed for different time periods. <A> You can find the following table by Dr Coggan, who is generally seen a benchmark for modern training methods here
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There is a lot of variability that determines how hard a person can work out for a specific amount of time - a few of the factors include: Genetics Amount of training Type of training (if you train only forlong periods, your ability to work hard at a high intensity will below, for example).
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Expected chainline from 103 mm bottom bracket to 107 mm bottom bracket? Frame Windsor - The Hour Hub Width - 120mm Stock Bottom Bracket Sizing - 68 x 103 mm Miche Bottom Bracket Sizing - 68 x 107 mm Miche Crank Set Requirements - 68 x 107 mm bottom bracket I'm looking to grab a pair of Miche cranks which call for a 107 mm bottom bracket (most likely the Miche primato). My bike currently has a 103 mm bottom bracket. Will the 2mm difference cause issues with my chain line? On Sheldon Brown's site, I read that 107 mm is best for 126 and 130 mm hub spacings. I've also read that the Miche Primato has adjustable cups for tuning alignment. Would this be enough to compensate for the extra 2 mm on the drive side. <Q> I agree with @Mac that you may not be able to tell the difference between 103 and 107. <S> If your current 103mm is in good shape, why not buy the new crankset and try it on the old bottom bracket? <S> Evaluate the chainline. <S> If it's good, you are done. <S> If the (front) chainring is too far inboard, buy the 107mm bottom bracket. <A> I could barely even tell it was different. <A> Track drivetrains can vary from 42mm to 46mm (measured from the centreline of the bike). <S> To complicate matters, Miche switched from ISO BBs to JIS BBs. <S> You can use a JIS (eg. <S> Shimano UN50-series) <S> BB with an ISO crank, but for the same chainline, the reqired JIS BB would be a few mm shorter than the correct ISO BB... <S> I'm not familiar with the frame in question but on a fixed/singlespeed drivetrain, the tooth profiles tend to be taller and wider to prevent derailing. <S> Running the chain out of alignment will increase wear. <S> tl;dr : <S> Measure the hub, then measure the chainring posision with whatever BB you have. <S> If the numbers don't match, change the BB.
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I replaced my stock 103mm BB with a 107mm BB and had no problems with the chainline. Crank manufacturers specify a BB length for a given chain line. If you use a BB that brings the crank inwards 2mm each side, the spider arms (where the chainring bolts on) may hit the chainstays.
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do I need to change my disc if the brake pads got oil on them In trying to change the brake pads on my mountain bike, I managed to get oil on my new pads and empty out all the brake fluid, and consequently also get some oil on the disc. I took the bike to the shop and they are now telling me I need to change the pads and the disc. I can understand the pads, but do I really need to change the disc or is the guy (girl actually) just scamming me. The disc is not soaking in oil, from what I can tell it just has a bit of oil here and there. <Q> First of all you need to tell the LBS (local bike shop) that the disk can be "fixed". <S> Then you need to find another LBS because they are either amateurs or are simply trying to make you buy stuff that you don't need. <S> You need to remove the oily disk from the bike and use a bike degreaser or alcohol on it to remove all oil. <S> Rub with a clean dry cloth or kitchen paper and repeat. <S> While finishing the process avoid touching the disk with bare hands on the face where the pads contact it because fingers leave grease as well. <S> Regarding your pads, these can be "fixed" as well in case they are sintered. <S> You'll clean them using a degreaser or alcohol and slightly grind them <S> (let's say remove <S> ~0.2 <S> mm of surface) <S> with a thin sand paper. <S> This will make sure that the pads are like new. <S> Then you'll do whatever you do when using new pads (bed them in). <S> If the pads are not sintered but are organic then the above process may not do the work because organic pads can suck some oil inside (like sponges but not that much). <S> I've heard of people boiling the pads in a frying pan with tap water and a bit of dishwasher soap <S> but I don't know whether this will work. <S> If you do that make sure you don't inhale any of the steam and also use an old pan which you'll never ever going to use again for cooking. <A> <A> Degreaser or brake cleaner should be just fine on the disks. <S> I've had success with just rinsing pads in boiling water - the heat drives off the oil.
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Just to add to the top answer - brake cleaner (sold by bike shops and car service places) is the ideal product for cleaning your brakes - just spray it on liberally and let it drip off.
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Tightening a quick release wheel and having one spring I’m fairly new to mountain biking and I’ve recently removed a quick release wheel and I’m trying to reattach it. However if I tighten it too much it makes a squeak noise around the axle. Also I’ve noticed that I only have one spring and I’m sure I’ve bought it from the shop like that. Anyway my question is should the quick release nut be tighten as much as physically possible? And also is it safe & normal for a bike to have only one spring (on the quick release)? <Q> The springs simply keep the quick release (QR) skewer centered in the wheel hub, making it easier to insert the hub (and wheel) into the frame dropouts. <S> It has no safety function other than to facilitate seating the wheel correctly. <S> If the wheel is not seated correctly in the drops when you tighten the QR then you run the risk of the wheel coming out during a ride. <S> That said, this is true whether or not you still have the QR springs. <S> When tightening the QR, it should be tight enough that the QR lever leaves a mark in the palm of your hand. <S> Finally, if you are getting a squeaky metal noise your single QR spring may be on backwards, or as pointed out by Daniel R Hicks' comment, the two springs could have gotten combined together. <S> First check to see that you only indeed only have one spring and that two springs haven't gotten entangled. <S> When placing the springs back on the QR, the narrow end should point toward the hub, the wide end toward the end of the QR skewer. <A> Perhaps a more objective rule of thumb regarding skewer tightness it that you should begin to feel resistance when the skewer handle <S> is halfway closed, which is when it's sticking straight out <S> (in-line/parallel with the hub). <S> My experience has been if it begins to tighten before half-way, it won't close without leaving more than an impression in my palm. <S> And if too loose, the pressure to complete the closure just doesn't "ramp-up" the last several millimeters, so open it back up and give it another half turn and see then. <A> If you're missing a spring from your QR Skewer, you'll be fine. <S> I only have one spring at the moment also and haven't had any issues. <S> As for tightening the nut before locking the QR down, it should be tight, but not too tight so that you don't bend the QR lever. <S> You shouldn't have to break a sweat to close the lever.
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If the spring was installed backwards the wide end of the spring can get jammed into the frame and hub axle, potentially making a squeaking noise when tightening the QR.
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Are tubular tires still used today? I bought an older second-hand racing bike, which has tubular tires mounted. I went to a bike shop and wanted to buy a spare tubular tire, but they told me: Wow, such an old bike! No, we don't have tubular tires. No shop has them. They are not used anymore nowadays. Instead, use an inner tube an a tire. Is that true? If so, why? <Q> I alternated tubulars and clinchers (different wheelsets) on my commuter bike for over a year <S> and it was clear that I had fewer punctures with tubulars. <S> In fact, I have so few punctures that I have to reglue tires after a year or so since the glue dries up. <S> YMMV. <S> when a tubular does flat, you almost never get a catastrophic deflation (bang), you get slow leaks. <S> if you're careful you can ride on a flat. <S> I finished the last mile (uphill) of a race on a flat. <S> they are more comfortable, especially when cornering because of the suppleness of the side walls. <S> you can get a sub 1500 gram wheelset for well under $500 (Campy Record and Mavic Reflex). <S> Try that with clinchers. <S> Tubular wheelsets are generally much lighter than clinchers. <S> if you do get a slow leak, tufo or stan's tire sealant will almost certainly fix it. <S> Now all of my bikes run tubulars. <S> For my commuter bike I use Tufos which last forever despite the broken glass that you inevitably see on roads. <S> For racing Veloflex are superb. <S> Once you get the hang of gluing, it's not really a big deal. <S> The main disadvantage in cyclocross is that you need multiple wheelsets to be able to shift tires on short notice due to weather changes. <S> Dry vs mud, say, requires two completely different treads. <S> See: http://www.worldclasscycles.com/tubulars.htm <A> I also got a set of tubular rims with an old vintage racing bike <S> and I've stuck with them. <S> I don't find them to be a hassle, but gluing does take a little technique and practice to be able to do it neatly. <S> With sealant, I rarely have to change tires, so I find myself gluing a new rear tire about once every 2k miles. <S> You can find tubular road tires at bike shops and online at places like: <S> http://www.biketiresdirect.com/search/tubular-road-tires http://www.competitivecyclist.com/components/tires.39.html and others <S> I'm sure. <S> What you'll find is there aren't as many sizes and brands as clincher tires, but there is a decent selection. <S> The two tires I'm riding on right now, and the two hanging in my garage have come off of eBay. <A> Tubular tires are very common in cyclecross; their construction and the way they mount to the rim make it possible to run a lower tire pressure. <A> Tubular tyres are still popular with racers and many others. <S> It is most certainly not true to say that no shop has them or that they are not used these days. <S> One of their most overlooked advantages is that carbon wheels for tubs are cheaper than their equivalents for clinchers. <S> Personally, I love riding tubulars and only use clinchers on my indoor training bicycle! <A> I've only ridden on tubs, have not had a flat in 25 years <S> and I find the gluing process zen like. <S> Never used the tape. <S> I have veloflex Carbon tubs on carbon rims on my Cervelo and various tubs Vittoria, gommitalia, contis, challenge etc on 19 vintage Italian bikes that I ride. <S> Mind you those Italian Steels are babied, not ridden on gravel! <S> I am religious about tire pressure and inspecting the tubs after each ride, pulling out glass shards etc. <S> I also let some air out to rest the tubs after each ride. <S> You can check out some of my collection .
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And as was mentioned tubulars dominate the cyclocross scene. I think most people who haven't done it are afraid of the gluing, but if you like to tinker with things its not difficult. Finally, for most places in the US you have little choice but to buy your tubulars off the web since the LBS is unlikely to stock them.
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Fix / clean or throw away tire with 30+ thorn punctures? I recently rode through a horrible thorn patch. I came out with 2 flat tires. Upon examination, I found that the tube was punctured in 10+ places. Throw away. The tire has 30+ small thorns in it. Some thorns go all the way through, others are lodged in the tire without piercing through. Do I throw away the tire? Can I remove the thorns, and keep using the tire? <Q> When you remove all the thorns very carefully you could keep using the tire. <S> Unfortunately this might be some hassle with 30+ thorns and you can not be a 100% sure that you really have removed all of them. <S> Also some may have broken off in a way that you see the remains from neither inside nor outside but the remains may be pushed further inside after some time of usage causing a new flat. <S> Therefore my advice would be: If you can afford it you're better off with a new tire. <S> If you want to save the money, try to very carefully remove all the thorns you see or feel. <S> Especially on the inside you should check the tire with your fingers if there's something sticking through. <S> Even then you will have to look out for a higher puncture probability that means you should be prepared to deal with it, i.e. carry an extra spare tube and a repair kit if you don't do this already. <A> I believe you'd eventually have more time than it's worth trying to remove the thorns, so just scrap the tire(s) and get new tubes as well. <S> That should save you time repairing the tubes as any missed thorns work their way through the tire carcass. <S> It's bad enough hunting down shards of glass inside a tire, much less small thorns of the numbers you have. <A> Can you afford a new tyre without it being a big deal to you? <S> You'll then have to take time to fix the puncture and, possibly but less likely, fatal damage to the tube. <S> It's unlikely you'll lose money by not replacing the tyre, but you may lose time. <S> Which matters more to you? <A> I vote replace it! <S> Since you road through a thorn patch, I am going to assume you ride off road/trails often. <S> Off road riding puts a lot of stress on tires, so you could have issues way sooner than later. <S> It allows too much exposure to your tubes. <S> Smalls pinprick holes can become real problems creating pinch flats or let debris into the tire. <S> Especially if you ride on rough terrain, gravelly roads or real hot asphalt. <S> Being stranded due to flat tire(s) is no fun, especially when tires can be replaced cheap enough. <S> Mike <A> Why not leave this tire for another bike (like whatever-junk-left commuter) where you could simply put a tube with sealant?
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If you don't replace the tyre there's a decent chance that you will suffer an additional puncture from a thorn you miss.
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Safe saddles for men's health As a continuation to Why is it important to have good saddles? I would like to know: Are there non-expensive saddles that are safe for men's health that you can advise. A slightly different question, are there saddles that are safe for men with urology problems? For example, this is what I found in the mentioned question. Fortunately, there are several types of seats that can help alleviate that pressure and prevent injury. Look for seats with a split saddle, or one with a space in the area that would normally press into the perineum. This means that there are such saddles, but can you mention any models? <Q> No saddles exist which are unsafe for mens' health. <S> What exists are saddles which do not fit particular bodies and, most importantly, misconfigured saddles and bad riding postures which can give a man some health issues. <A> All of their models have no nose to the saddle, so the rider sits further forward on the seat, removing the pressure area that frequently occurs with saddles. <S> I ride them on all of my bikes and have had no issues after switching to them with pressure and pain in the perineum area. <A> There are several different makers and models that are designed to be comfortable and safe for men. <S> However, if you have known urogenital issues, then I would get with your doctor and go through some of the available models and see <S> which one he/ <S> she would recommend. <S> Once you have recommendations, then I would find a bike shop that lets you trial saddles for a short basis, as saddle fit and comfort are highly unique from individual to individual.
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ISM makes saddles that reduce pressure on the perineum and according to their Marketing Material is better for riding and having adequate blood flow.
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Disc brake rotor size and forks strength I have been told that every fork has a maximum rotor size characteristic. For example, for my $75 Suntour this is listed as 185mm. The explaination that I have been given for this limitation is that any larger rotor will have significant chance of breaking the forks ! That is, the braking force will be too high and the brake mount system will shutter. Is this correct and precise information or is it just some legal insurance? <Q> My guess is its not so much about the forks themselves breaking <S> - I cannot imagine that sort of force can be generated by brakes when the forks themselves have to handle the forces generated in prangs etc that would easily exceed any braking forces..... <S> Yep - forks break in a bad prang, but no one would buy forks that did not survive a moderate fall without damage <S> The failure point is most likely the mounting posts, or the wheel being loosened or even ejected by the brakes on a QR system (well known issue and one argument for through axles). <S> However, the idea that bigger disks give more braking and bigger forces is overly simplistic. <S> A cheap setup with 200mm discs ridden by a 100pound wimp will not produce the same force as a top quality 160mm disc ridden by a guy with the weight and strength of a gorilla..... <S> I believe its most likely the manufactures covering themselves and weasel words to get out of warranty claims from guys who buy cheap shocks, put on the biggest brakes they can find and ride them on the biggest drops they can find - and then claim "It broke.......". <S> The kind of guys that do this would not be seen dead on a bike with small discs..... <A> Ok, I like the above two answers a lot ... since they say what I want to hear. <S> However, here is what SR SunTour responded to my official support request (after less than two hours of the request!) <S> : <S> Dear Mr. Vitkov, the leverage is much higher if you go for a bigger rotor than 185mm. <S> You risk that the fork breaks if you go for a 203mm rotor!! <S> So we strongly recommend not to do this if you don´t want to get seriously injured! <S> For most riders a 185mm rotor is more than enough. <S> Best regards Benjamin Rees <S> I still do not know what to believe. <S> For example, I do not know of 185mm rotors, the closest I have seen is 180mm. <S> One possibility that I can think of is that the stanchion tubes could brake off the lower tubes at very high deceleration. <S> However, deceleration is as much function of the rotor size as of the brake type e.g. high-quality hydraulic or the cheapest mechanical brake. <A> cherouvim nailed it in the comment. <S> First, imagine the case where somehow (maybe a system of gears) <S> the rearmost edge of the disc rotor were inside the fork itself. <S> When the pads grip the rotor, the rotor tries to push the brake assembly up further into the fork. <S> Most materials would fare very well under this arrangement. <S> Let's call this the 0° case. <S> Now, think about the current case. <S> The force is still almost along the axis of the fork, but slightly further out, so there's some "sideways" torque being applied to the fork. <S> This is maybe 5-10°, but the larger the rotor, the more torque. <S> Finally, the claim that rim brakes are just disc brakes with large rotors. <S> This isn't right, because rim brakes are not anchored at the end of the fork. <S> That's the 90° case. <A> Why greater rotor puts more stress on fork (no matter how and where the caliper is mounted) from physics point of view : Friction depends on the materials touching and the force they are pushed together. <S> The materials depend on the quality of rotor/pads. <S> The force depends on how hard you can squeeze the brake lever and also on quality of the brake (caliper design, brake hose strength against stretch, brake fluid, etc.). <S> So given a brake and given how strong your fingers are the brake's maximum friction force it is able to generate is always the same. <S> Now - the further the braking point is from the center of rotation <S> the more leverage there is and the greater braking torque can be achieved. <S> Higher braking torque puts more stress on the fork. <S> The other thing and non-relevant is if you can use all that braking torque. <S> That depends on the weight of the rider, the tire (contact patch and tire tread), and the ground (asphalt, gravel, mud, ice,..).
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If you imagine ideal calipers anchored at the bottom of the fork that could grab the rim at the back (where a huge disc brake rotor would) with force equivalent to a disc brake system, they'd probably snap the end of the fork off (or the brake mount itself) very easily. Another controversial point is that their more expensive forks - EPICON and AXON also are limited to 185mm, I managed to locate only 1 fork limited to 210mm - a dirt jump intended one.
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Tri-bars/Aerobars on Mountain Bikes I am trying to work on endurance in the hopes of one day touring the GDMBR in a reasonable amount of time and after watching Ride the Divide , I noticed a lot of the riders are using aerobars. When I am training, I can ride close to 40 miles on my bike with a Specialized flat bar but I am noticing significant pain in my back, tailbone, wrists and shoulders. Are aerobars the answer to my pain problems? My assumption (from purely a comfort viewpoint) is that aerobars allow you to shift your weight occasionally and distribute your weight differently without stopping. If so, is there a certain type of handlebar I should be looking at for a mountain bike? I would prefer an easy to install/uninstall solution because I am not always looking to have these handlebars on. Also, is adding an aerobar the proper solution or am I looking at it wrong? I am questioning bikes at the moment and would be grateful on any tips. I have never used any other type of handlebar other than a flat bar, so please include anything that may seem incredibly obvious. Note: I looked at this answer but those look incredibly uncomfortable for long distances and seem pointless for what I am doing. Specifications Bike Specialized Myka Sport 29er Handle Bar Specs Specialized flat bar, alloy, 640mm & 660mm wide, 8-degree backsweep, 4-degree upsweep, 25.4mm Full Specifications <Q> The longer the distance, the more this will hold true. <S> This picture is of a top triathlete. <S> Note that the forearms are almost parallel, and the upper arms are at a 90 degree angle. <S> This allows the main support for the upper body to rest on the bone structure, with minimal muscle involvement. <S> (Stadler was an Ironman distance triathlete, bike segment of 112 miles). <S> While you may see variations on this, it is a general truism that the longer the race, the more comfort trumps aerodynamics, and vice versa (Short races aerodynamics trumps comfort.) <S> Many of the ultra mountain bike competitors set up their rides similarly, and have "wrap" style aerobars that allow them multiple different hand positions for control, as well as the resting position where their arm muscles don't have to do the work for support. <S> That all being said, I would point out that many riders go much further than 40 miles with no pain at all. <S> This would suggest to me that your fit is not correct, or that you are not in shape enough for a 40 mile ride yet. <S> Tailbone pain is (usually) a bad saddle and fit, and the rest is also easily attributable to fit. <S> Aerobars will not be a magic cureall for an improperly fitted bike <A> I see a few potential problems with mounting aero bars on a mtn bike. <S> The biggest concern I would have would be maintaining control of the bike. <S> Aero-bars are great for straight, flat and smooth paved roads, but I wouldn't think they would be great when riding on mountain paths. <S> If it is packed gravel the entire way and you feel comfortable riding on aero-bars then go for it. <S> The other main issue I see is not being able to brake or shift while in the aero position. <S> Aero-bars will take a while to get used to and may require you to change seat position to be comfortable in the aero position. <S> The aero position puts stress on your lower back and glutes due to the collapsed position. <S> As a road cyclist, I prefer riding my road bike for longer rides over my Time Trial bike due to the comfort and increased control <S> and I have never considered putting aero bars on a mtn bike, but I ride mountain trails and not packed gravel. <A> Non-aerobar possibilities for you, specifically aimed at increasing the number of available hand positions, may include: <S> Regular old drop bars, possibly with a raised stem if a roadie bent-over stance is not comfortable for you <S> (there's no rule that drop bars have to be lower than saddle height!) <S> "Bullhorn" bars "Moustache" bars "Butterfly, <S> " "touring," or "trekking" bars. <S> If drop bars don't do it for you, these may be the next best thing. <S> They are especially popular in Europe and among long-distance cycling tourists; in the US you'll almost certainly have to special-order them, but Nitto and Velo Orange have them. <S> Personally, I can't even with drop bars -- keep those things FAR away from me! <S> -- <S> but I love my VO Trekking bars despite their persistent creak. <S> Any of these bar types should have a variant that is fittable to your mountain bike, <S> though putting your controls onto butterfly/trekking bars can be an adventure, and you may find that you need a different stem as well (for length, or for correct angle). <S> The inimitable Sheldon has a handlebars page with pictures, OR your search engine of choice will turn up plenty of pictures, OR check around Bicycles SE for the "handlebars" hashtag . <S> Handlebars are fairly reasonably priced, as components go. <S> You can mess around a bit and not spend too much, if you're willing to put up with the hassle of attaching and detaching brakes, shifters, etc. <S> Swap meets may also be a good source of handlebars, because other people experiment too. <S> Good luck! <A> I have had my aerobars (profile designs t1+) on my mtb for about 2 years. <S> The GDMBR was my inspiration for doing so <S> and they have allowed me to ride over 100 miles. <S> It is so much more comfortable than only gripping the handlebars. <S> Of that 100 miles I probably rode only 15 miles sitting up holding onto the grips--the rest of the time: aerobars. <S> I like the t1 <S> + because it allows me to adjust the armrests closer to my body and further behind the handlebars. <S> This way I am not leaning over as far---just a comfort thing for me. <S> My advice: really do some homework on different aerobars and see what features they offer because they are not all the same. <S> SOme allow you to position the armrests further apart, some allow you do adjust them closer or further from your body, etc. <S> really access what your needs are and make your purchase accordingly. <S> Gud Luk <S> One last thing:
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The main reason that aerobars may have an advantage over flat or road bars is that they are designed so that your main support mechanism is skeletal, rather than muscular. The right handlebars make a world of difference to comfort. don't get tt bars unless you want your wrists to be so sore you wont be able to pick your nose due to the excessive bend and strain put on them
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Will I notice the benefits of changing wheels? I've got a 2010 Specialized Tarmac Comp. The wheels are Mavic Aksiums and are pretty well known to be dam heavy (but sturdy) I'm seriously considering swapping them for something like Fulcrum Racing 3's, that alone should save around 500g I've never ridden another bike and never changed wheels before so will I notice a reasonable difference and do you think its worth swapping them for something like the Fulcrums? Interested in peoples opinions pros/cons. I weigh 80kgs ride a mixture of flat to very hilly terrain and approximately 80-100 miles / week <Q> I think probably swapping your wheels out is just about the single biggest improvement you can make to a bike in terms of performance. <S> I did this last year and love the new wheels. <S> I too was riding Aksiums (I think) and bought some Fast Forwards. <S> Qualitatively I am very impressed (but then I should be, if you boil everything down to money the FFwds cost 5x a set of Aksiums). <S> Quantitatively, its difficult to say how noticeable the change is. <S> (I certainly notice being blown across the road sometimes (6cm rims), but that I'm not sure that counts!) <S> But now the caveat..... <S> it all depends what you swap them for. <S> I have no experience of Fulcrums so can't say how good that particular swap would be. <S> Possibly someone else could help there. <S> All I would note is that they're still toward the lower end of the price range (when you think you could spent thousands on wheels), so possibly they might not make as much difference as you'd hope. <S> But as I say that's based on a hunch rather than direct knowledge. <S> One other point: <S> not so long ago I had a spoke go on the Ffwds. <S> Was a real pain in the ass to get a replacement (they were fancy bladed DT Swiss spokes and you're always recommended to change like for like). <S> Nobody in the UK could sell me just a handful of spokes, only a box of them at about £100. <S> In the end I found a place in the US who would sell them singly, just for a dollar or two, but it cost in terms of delivery and duty. <S> I'm just saying, whatever wheelset you get it might be worth making sure you can source spares for it easily. <A> I switched from Aksiums (2010, they weigh around 1900 grams without skewers) to Ksyrium Equipes (2005, slightly lighter, but I never verified the weight). <S> I never noticed a difference in how the wheels felt or spun up, but someone else might. <S> In a nutshell, professional riders noticed an increase of a few ounces, but non-professionals did not notice until nearly a pound of lead was added. <S> You don't mention how much you weigh, or how much/where you ride. <S> I'm around 200lbs (91kg) <S> and I average 50 miles (80 km)/week. <S> Some climbing, mostly flat terrain. <S> I'm not racing, so my primary concern is solid wheels which are not high-maintenance and represent good value, last a long time, etc. <S> I got tired of broken spokes on the rear wheel when I was riding Mavics, so I switched to these . <S> My $0.02 would be to get wheels that fit the kind of riding you're doing. <S> In my own case, the Mavic Ksyrium Equipes were a foolish choice, in hindsight. <S> I got them off eBay for a good price, but I didn't find out they were 2005s until I got them, and after three broken spokes ($30 each to fix at my LBS) in 3,000 miles, I decided to get something that required less maintenance. <S> Mavic wheels use proprietary spokes, which many LBS do not keep in stock. <S> There is enough information out there on the 'Net to make it clear that Mavic wheels are not made for 90kg+ riders, and I should have done my homework more carefully. <S> I would encourage you to do yours. <A> I have a 2013 Specialized Roubaix that came with some pretty heavy DT Axis 1.0 wheels. <S> I upgraded to Fulcrum Racing 3's and couldn't be happier. <S> The people who claim that they aren't faster are missing out on a very important thing. <S> The hubs. <S> They just roll and roll and roll. <S> They also climb much better. <S> They are stiffer. <S> All around better wheels. <S> After a few weeks I swapped back to the DT's for a day just to see if the difference was just in my head. <S> And man, do they feel slow and heavy. <S> Do it, you won't regret the purchase. <S> And if you aren't happy, I'll buy em off you for my 2nd bike! <A> I had some low-spoke, rigid rims that were more suited for racing that just riding around (even though I try to ride around with speed!). <S> I rode those for a number of years, then replaced them with 32-spoke rims (Mavic Open Pro). <S> Holy cow, what a difference! <S> Bike rides so smoothly now. <S> Like a completely different bicycle. <S> So, yeah, in some cases, big difference.
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I think I'd be better off losing some weight than paying big money for lighter wheels, but I might think differently if I was lighter and doing a lot of climbing. I didn't see my average speeds jump or anything, at least not enough to notice. A bicycle mechanic friend related an anecdote regarding someone who once tested how sensitive riders were to added weight (in the form of lead weights in the seat tube) on a bike. The actual weight of a wheelset often differs from the published/claimed weight.
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What is considered a good "safe biking distance" to bike to work? I'm curious about what is the maximum distance you can live from work so that it's a reasonable biking distance. I am interested in biking about 30 minutes to work. It would be about 5 miles away. I have a heavy cruiser bicycle (Schwinn). It would be a leisurely ride. <Q> A good safe biking distance is the distance that one can enjoy the bike ride to work, get there a few minutes early to clean up or shower and after work enjoy another bike ride home and still spare some time to spend with family/ loved ones/have a life besides work and the commute. <S> I limit my bike commute to about an hour each way. <A> Safety hazards increase as you get tired <S> , it will affect your judgment and reaction speed. <S> You can get a guess on that by doing some trial riding. <S> One thing that is for sure is that the more you ride, the safer you will feel. <S> Your body will adapt to cycling and you will feel less tired day-by-day, and be more confident about yourself on the streets. <A> Other answers have touched on this but not explicitly. <S> If you're exhausted and can't keep a straight line up a busy hill, don't think to look over your shoulder in time etc. <S> , that's bad and getting dangerous. <S> tiredness can really hit your judgement and reaction times. <S> Otherwise it depends on your starting level of fitness and facilities in work more than safety. <S> Now I'll happily do 4 days in a week if it fits in, and would try every day but haven't had the chance. <S> I would say that the bike doesn't make that much difference at the scale of your ride or mine - with the obvious caveat that it fits reasonably well and isn't in a terrible condition or something weird. <S> If it's OK on a cruiser it will be better on a road bike or hybrid (my choice for urban riding given the state of the roads/hills and the need to see over cars), but if you find it horrible on a cruiser, you wouldn't find it a pleasure on an unfamiliar road bike. <S> Of course, if you're at risk of heart attacks, recovering from an injury or whatever <S> it's a different matter. <A> Traffic, weather, and geography would make a world of difference. <S> On a dry day at 68°F, 10 miles would be great. <S> If you have to take several pedestrian bridges to cross major arteries in hot, humid weather, even 1 mile could wear on you. <S> I do 1.55 miles with pretty-much no traffic (crossing one semi-major road to get to work), but this Florida weather does makes it easier for me to make excuses during the summer. <S> Until recently, I was commuting by car about 53 miles to work one-way. <S> I once considered doing the commute by bicycle on a Friday, getting up extremely early in the morning and coming home just-about dead. <S> (We have a shower at work.) <S> If you already have this job, maybe a one-day tryout would be the way to go, or you could try simulating your commute on a weekend. <S> Not knowing your other factors, I would guess 5 miles would be no problem. <A> This is not really a safety issue, but one of practicality and convenience. <S> There is a shower at my work, but I don't use it unless I am truly soaked with sweat <S> (only needed if I take a long "detour"). <S> Even heavy rain is not a problem if you have a change of clothing. <A> The distance is really up to the individual. <S> If this is to be a daily commute, then you'll need to consider the weather at times. <S> It's just that at times when it's raining or the wind is blowing at 25mph, that five miles will seem like ten miles. <S> The safety part will be determined by the condition of the roads traveled, the amount of traffic, and how you must dress for your commute. <S> If the commute will be made only when conditions are acceptable as being "comfortable", then you should have no problem with using the Schwinn cruiser for the ride. <A> One thing also to consider is a minimum distance. <S> If you are a sweater (i.e. one who sweats) <S> a shower is a necessary part of bike commuting. <S> If you are going to take the time to get all your gear together, pack a change of clothes, and ride your bike, 5 miles is too short. <S> I sweat in 5 miles. <S> My minimum distance is 10 miles, and max is 15. <S> Anything more than that I can't sustain on a daily basis.
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The most important thing to consider is not the bike, but your clothing and amenities at your destination. It would depend on a lot of things, such as terrain, weather, traffic etc. The main safety point I would say is how you ride when you're tired. Five miles should be easy to cover with a cruiser type bicycle. I started from an occasional leisure ride by riding the 9-10 mile each way commute once a week for a couple of weeks, then twice, but not consecutive days. If you are not sure, simply ride a few kilometers and you would be in a position to guess. I commute a total of 6 miles each way, every day, rain-or-shine in a humid climate. I use a backpack and carry a change of clothes and my laptop (using plastic bags for protection from rain).
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Why did my tire just blow up? I finished a 2 hour bike ride outside today, and I parked it next to the wall in my kitchen after I got home. 3-4 hours later... all the sudden the front tire just "blew up". What happened? Thanks! <Q> Check the tire carefully for a split in the carcass. <S> There may have been a small split starting to appear, and leaving the bike in a position where the sun could come through a window and hit the bike, may have caused the tire pressure to increase enough to extend a split in the carcass enough so that the tube was forced through the tire <S> and it blew the tube. <S> I had a bike in the basement do this same thing. <S> I had changed the tube and didn't realize the tire had a small split in teh carcass. <S> I aired the tire up to the maximum and set it aside. <S> Apparently the sun coming in through a window had enough of an effect on the tire that it suddenly blew the tire right off of the rim! <A> Did you by any chance inflate the tire right before your ride? <S> Sounds like a delayed-reaction blowout. <S> (If so, I wince in sympathy -- same thing happened to me a couple of weeks ago.) <S> If you had a longish rip in the inner tube rather than a small hole or pair of holes, that's likely a blowout from overinflation. <A> I have had this happen a few times. <S> But most of the time, it was the tire not beading correctly. <S> If this is the problem, you will usually not see any evidence of this other than a blown tube. <S> The best way to prevent this is to pump your tire to about 15 PSI then visually inspect the tire all around the rim to make sure the bead is sitting perfectly even around the whole wheel. <S> A low PSI, like 15, allows you to adjust the tire by hand and still keeps it from sliding around too much <S> There is a small seam that should sit a few millimeters above the rim that helps you see that the tire is seated right.
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Sometimes it was due to mis-matched tire/rim max-PSI ratings (tire could handle a lot more pressure than the rim), or a ripped sidewall.
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My stem keeps moving side to side even thought I tighten it I just got a new Demolition Stem.I tight it with all my force And It keeps slipping side to side Like it doesnt match with the fork lined up And whenever I check it its fine but after a while it is always not lined up with the fork..Please help me <Q> Is it possible <S> you tightened the pinch bolts before tightening the bolt that runs vertically and holds the top cap down? <S> If you do that, the entire assembly won't be fixed tightly on the vertical and will allow side-to-side play. <S> I did that once and the symptoms were exactly as you describe. <S> To check this, loosen the pinch bolts and the bolt in the top cap. <S> Now tighten the top cap bolt first, then the pinch bolts. <S> Be very carefully while tightening the top cap. <S> If tightened to much, it can overload and ruin the headset bearings. <S> Here's an image from Sheldon's site showing the bolts <S> I mean: <A> I used to do the same thing when I first started riding <S> and I just helped 2 other people in the past 3 weeks with the same issue. <S> Once you understand how the fork/stem system work it makes more sense. <S> Back in the 80s, all the BMX necks tightened from inside the forks using a wedge, when they moved to the more modern necks, people still tried to tighten the forks using the bolt that is in the same location (I did too). <S> The best way to tighten your neck/forks is to loosen the stem bolts (A) then get the fork bolt (B) 'sung', do not tighten hardly at all <S> or you will lock up the headset. <S> Move the forks back and forth to ensure that they are not too tight, not too loose, but JUST RIGHT! <S> Then go back and tighten the stem bolts (these you can crank on if you like, but they usually recommend less than 100 lbs) <A> When you tighten the pinch bolts of a stem, you should notice how the gap around the steerer closes. <S> If it closes so much as the two sides touch, it is more likely that any further tightening will only press one side against the other, not around the steerer, which will give the described symptom. <S> This observation should also be made when tightening the handlebar clamp. <S> However, this situation will only arise in case of a size mismatch, on in a really severe case of worn components. <S> The latter will usually be detectable by simple inspection, but is less likely. <S> Another cause known to me for the described symptom is that there where "dust" trapped between the stem and the steerer. <S> This dust is wear byproduct, it is actually metallic. <S> I believe that this dust is ball-bearing like, so it allows pieces to slip even if properly tightened. <S> The solution here is to clean the components prior to assembly. <S> (This effect actually happened to me with an aluminium frame and a titanium seatpost. <S> The seatpost was wearing down the seat tube, generating this "dust". <S> In such situation the seatpost would lower itself by just riding the bike. <S> The solution was to exchange the seatpost for one with a smoother surface)
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One of the most common reasons for this in a new BMX bike is that the riders tighten the fork bolt without loosening the stem bolts.
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Tips to Alleviate Hand Soreness I've recently switched from a hybrid with straight bars to a touring bike with conventional drop bars. My commute is just over 5km, and my palms have been getting very sore just below my thumb. My theory is that my saddle is angled too far forward and I'm resting too much of my weight on my hands. Is there anything else I should try adjusting? Are my hands still getting used to the new more aggressive riding position? Any other tips for someone getting used to drop bars? Edit : I am 6'3" and the bike's frame is 60cm. <Q> The solutions many people try for hand soreness include: <S> Padded gloves <S> Padded bar tape/gel inserts under the bar tape Raising the bars, either by moving the stem up if you have spacers above it, flipping over an angled stem or getting a new stem. <S> Tilting the saddle backwards so that the hands aren't having push on the bars to counter you sliding forwards. <A> In my experience, the pain is caused mainly due to shoving the soft part of palm(between thumb and index/fore finger) on to the brake hoods. <S> Try resting your 'karate chopping' part of your hand on the bars when reaching the brake-hoods. <S> My pain was significantly reduced in doing so. <S> I think getting a professional bike fit is a good investment if you are considering riding your cycle on a daily basis. <S> Using padded gloved while riding reduces the affects of road vibration and hence alleviate some of this pain. <A> How far is you saddle tilted forward? <S> A good rule of thumb is that the saddle's upper deck should be more or less level. <S> If you have a very short frame, you might even try to tilt the saddle's nose slightly upward. <S> It might also just be that your lower back musculature is not (yet) strong enough to hold (enough of) <S> your weight, now that you seem to ride more bent over. <S> This could also lead to more load on the hands and shoulders. <A> I once ran through some mathematical calculations, taking into consideration body weight, blood pressure, the area of the hand in contact with the handlebar, etc. <S> The net (close as I recall) is that, if you are supporting most of your upper body weight with your hands (vs back) and you weight much more than about 150 pounds then the pressure on the hands will inevitably cut off blood circulation. <S> So basically it's necessary to somehow vary the contact area regularly, so that bloodflow is not deprived of any area of the hand for too long (more than maybe 5-10 minutes). <S> With drop bars you have a number of possible hand positions, so varying position is not too hard so long as you remember. <S> (One tends to forget when one gets tired, though.) <S> I also once had a pair of gloves that had a pad in them made of ribbed rubber that circumvented this problem nicely. <S> The ribbing meant that blood could flow between the ribs so that even slight changes in hand position would keep the blood flowing (and possibly the ribbing served to "pump" the blood as well). <S> Unfortunately the gloves wore out <S> and I never found another pair (gel gloves came into vogue and pushed out any other options). <S> I then experimented with placing a ribbed surface on the bar and found this so effective that I could ride for hours without gloves, but <S> I kinda stopped long touring and so never pursued it more. <A> Tighten your core; this will take most of the weight off the hands. <S> The more aggressive position requires you to use more of your body. <S> If you don't engage your core, your hands will adapt, but you won't be getting the most out of the position. <S> It's worth noting that engaging the core will also make for a safer ride. <S> You will have better control of the brakes as your hands will have more strength (and feeling) for the brakes and the shifters while at the same time your lower body will be more connected allowing you to control the bike much easier. <S> This is something that you will have to think about as you ride for the first week or so, but will become natural quickly. <S> I would also note that the "equipment" suggestions, while they may offer a bit of relief, generally only extend the problem. <S> The exception is bike fit which is critical, <S> if you haven't had a good bike fit, I'd recommend getting one from a Physical Therapist that specializes in bike fits. <S> If "BikeFit" is available in your area, they are very good as well.
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The saddle being set up too high may also cause the rider to exert more pressure on the hands. Padded gloves or bars only slightly increase the size of contact area and thus only slightly raise the amount of weight that can be supported. Getting a professional bike fit.
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How does a chainstay length affect a mountain bike performance? (wrt: 26", 650B, 29r) The trade offs for 26" through to 29" with respect to rolling resistance, contact patch, obstacle rollover, etc... have been well discussed. However, it occurs to me that as the rear wheel gets larger the clearance eventually requires the chain stay length to increase to accommodate the wheel. How does a chainstay length affect a mountain bike performance? <Q> All else being equal, longer chainstays equate to a longer wheelbase, and the rear wheel trailing further behind you. <S> You are correct in your assertion that as wheel size increases so too does chainstay length, though many manufacturers have put considerable effort into minimizing this and as such the increased chainstay length is not directly proportional to increased wheel radius. <S> For example, a 26" and 29" version of the same bike model are unlikely to have an inch and a half discrepancy in chainstay length. <S> That said, there are tradeoffs to be had in chainstay length differences. <S> As an analogy, think of a drag strip or hill climbing motorcycle vs a standard sport or dirt bike. <S> The first two examples have very elongated swingarms that put the rear tire well behind the rider and dramatically increase the wheelbase. <S> Those long swingarms are great for preventing the bike from looping out and maintaining straight line stability, but neither can turn or corner like the latter standard motorcycle examples. <S> That is a very exaggerated example, but the same principles apply to chainstay length differences on bicycles. <S> that much is just basic physics. <S> Keep in mind that chainstay length and wheelbase are just two factors in a multitude that determine how a bike will handle. <S> Also keep in mind that just because you have a bike with slightly longer chainstays doesn't mean you can't rail corners or navigate switchbacks, and just because you have <S> shorter chainstays doesn't mean you can't bomb descents- much of this comes down to technique, and you'll alter your technique to accommodate for any differences in your bike's handling characteristics. <A> benefits of short chainstay: very easy to manual/wheelie very easy to corner (just by "thinking") with minimal body movement and without turning the bars benefits of long chainstay: stability on high speeds (due to longer wheelbase) better/ <S> easier climbing <A> I think this discussion fails to mention two important physical consequences of longer chainstays: <S> all else being equal, a longer chainstay will flex more, and your body weight has more leverage: this gives either improved comfort or squishy bike depending on your view. <S> with a longer chainstay, there is more weight on the front wheel, so it will have more grip. <S> Basically it changes the weight balance and how you ride the bike in a turn or climbing. <S> Both are of practical importance on a mountain bike.
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Again, all else being equal, longer chainstays are going to be more stable at speed and typically provide better climbing traction, but they will cause the bike to not handle as sharply and to no turn as quickly-
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Compact gears and chains Wanting to know if you can use a compact crank and also use a compact cassette , I have placed both on my bike but the chain seems to be at the extreme when placing the chain in the smallest gear and then also the biggest gear.Or is this normal? <Q> This is probably normal, but if the chain goes slack in small/small or completely taught in big/big, you may need to adjust the length of your chain accordingly. <S> If it does both, you likely need a longer cage derailleur, but keep reading and you'll know how to check on that last case and know for certain. <S> Each cage length for a given derailleur is designed to take a minimum sprocket size, a maximum sprocket size, and a maximum number of teeth difference between running the bike in big chainring/big sprocket and small chainring/small sprocket known as "maximum capacity" or "total capacity". <S> That final number basically defines how much extra chain the derailleur cage can take up and thus how wide of a gear range you can run. <S> For example, a Shimano 105 RD-5700 rear derailleur has a minimum sprocket size of 11t, a maximum sprocket size of 28t, and a total capacity of 33t. <S> To find out whether your drivetrain is within the total capacity range of the rear derailleur that you're running, use the following formula: ([teeth on largest chainring] + [teeth on largest cog of cassette]) - (teeth on smallest chainring] - [teeth on smallest cog of cassette]) for a 50/34 crankset in combination with an 11/23 cassette, you would have ( 50 + 23 ) - ( 34 + 11 ) which is equivalent to 50 + 23 - 34 - 11 = 28 . <S> You might see different orderings of this formula, but it's simple arithmetic so the number will come out the same. <S> If the number comes out to less than or equal to your derailleur's total capacity rating then you should be fine. <S> It's worth noting that you can push this if you feel comfortable doing so, but it's likely that the gears you're supposed to stay out of anyway (the aforementioned big/big, or small/small) will become totally unusable. <S> For this reason it's probably best that you just adhere to the manufacturer's rating. <A> You need to adjust your chain length. <S> Either visit your local bike shop or do it yourself. <S> See Sheldon Brown's article on the subject of derailer adjustment that also covers chain length. <A> I don't know what a compact cassette is either, but any derailleur will have an upper limit on the size of the biggest cog (shortest gear). <S> Maybe you need a long cage derailleur?
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If you just replaced your chain rings and sprockets with smaller ones, that is to be expected.
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smaller wheels on big bike to reduce height I have a SEKAI sprint 1000 bike which is a tiny bit big for me as I have problems reaching with my feet to the ground. The existing seat is already down to the lowest level so can't reduce the height any further.What I am thinking is to change the wheel to a smaller size. The current size is 27 1/4" (rim). Can I install smaller wheel on this bike without having replace virtually everything? If there is a seat available which has slightly lower seat frame so that if I replace the seat then it goes a bit lower (hope this makes sense?) <Q> The first problem with changing the wheel size is surely the brakes. <S> Assuming they're rim brakes, they won't be in the right place for a smaller wheel. <S> In any case, is it the distance to the ground that is an issue or the distance to the pedals? <S> If it's the latter, then changing the wheel size won't help, however, you might get an extra 5 or 10 mm by using shorter cranks - if this is appropriate for your height. <S> I would imagine that it's probably better and not much more expensive to trade the whole bike in for one which fits you. <A> As many others have stated it is possible to mount smaller wheels. <S> The issue will be mainly a cost versus return on investment. <S> The brakes may be able to be adjusted to reach and the frame may be spread to fit the wider hubs. <S> The google images I have seen of a SEKAI sprint 1000 appear to be an older 10 speed. <S> It most likely is equipped with a 5 gear freewheel using a 5 speed chain. <S> The more modern and smaller diameter 700 c and 650b size wheels will most likely use a cassette with at least a 8 gears. <S> This means your old crank, derailleurs and chain may be incompatable with the new wheel. <S> The 8 speed chain may be too narrow to fit on your present crank and <S> your old chain may be too wide to fit on the cassette <A> The question I would want to know is... <S> how old are you and how tall you currently are? <S> If you are young, like early teens, it's likely you'll be growing a few more inches, so you may not need to convert the bike wheels to a smaller size, ( that's asking for more problems with braking accuracy on the rims ), and trying to find a different seat. <S> This may cause your riding position to be way off in the saddle to pedal height. <S> As other posters indicated, you'll be changing parts to try and fit a bike to your body size, and spend money and time accomplishing this task. <S> You may be able to find a bike that fits you that can be ridden for a season or two until you grow into this bike. <A> 20 inch wheels on full suspension 'trial' frame and MTB frame with high Bottom Bracket. <S> But the frame must have disc brake mounts, very difficult to change rim brakes position. <S> And you may need shorter crank arms. <S> Lowering the rear axle with the suspension will also shorten the steering trail, making it easier to turn sharp corners. <S> I put a 19 inch moped tire on a motorcycle rim, (tire being 23.25” O.D.) <S> In place of my 24 inch bicycle tire. <S> It increased the trail of the steering a very small amount, but still rideable. <S> You can use a 16 inch motorcycle tire (20 inch O.D.) on a BMX rim. <S> It will lower the crank only one inch.
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Changing a bike with 26” tires to 24” tires would be easy, if it has disc brakes. If you are much older than early teens and have reached your growth potential, I'd consider finding a bike of the proper frame size so you can enjoy the bike rather than curse at its short comings and spend money on something you may not be happy with as far as results. Bicycle wheels and motorbike wheels are measured differently, a motor cycle wheel is measured at the tire bead surface and its diameter is the actual number of inches it is stated to be, a pedal bike rim is measured at the outside diameter of its tire. A 17” (rim) moped tire on the rear may help with a 16” (rim) on the front.
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How to fix/prevent blocked cleat bolts I've had my SPD touring shoes for about seven years. The cleats are the originals and are now quite worn and I noticed recently that one of them (not pictured) is at a rather wacky angle that can't be doing my pedalling action any good. As the shoes are more or less OK, I'd like to replace the cleats. The problem is that the cleat bolts (hex-shaped) are jammed with grit, mud, stones and whatever else I've walked on in the past 7 years. So the allen key won't go in. Last night I tried picking the dirt out with needle-nose pliers, chiselling it with a nail and hammer and even resorted to trying to drill the bolt out. This last attempt barely damaged the bolt, but heated it up so much the bottom of the shoe started to melt. Is there any way to prevent this from happening or to fix it when it does? <Q> Try a pipe nipple extractor or similar stripped screw extractor <S> (Example: http://www.plumbingsupply.com/extractors.html ). <S> It is designed to grip the inside sides of a pipe using the same turning direction that will unscrew it. <S> It shouldn't need much depth to work and it will try to drill itself in. <S> You may still have to drill some of the junk out, but go slow and select a bit that is smaller than the head opening. <A> I've had a similar question in mind for a while. <S> It's pretty soft, so you may have to re-apply often, but it would be easier than removing destroyed bolts! <S> I am going to try this next time I install new cleats! <A> I've used the edge of a blunt'ish steak knife in the past and it has worked a treat. <S> The tip fits perfectly down inside the bolt, pick out dirt and grit then return to cutlery draw for future use! <A> I tried with bathroom sealant (supposed to be white, but dried clear/grey). <S> After a couple of months cycling in all weathers it's still in there. <S> Seems like a cheap and easy solution. <S> Shown below in the right hex-bolt only. <S> I'll now be adding this to the other bolts too. <S> (Some credit should go to Darren Cope who suggested something very similar). <A> I've got heaps of torx bits from various old sets. <S> For me that's holding it in a vice and using a long-arm socket ratchet while pushing down. <S> Expect the torx bit to be sacrificial, they tend to round off or snap the tips off. <S> You can file them flat on the end for the second bolt. <S> First though, pre-soak the area in penetrating oil to try and free up the threads. <A> This isn't that big of a deal to clear up. <S> Just use the tip of a metal pick to scrape out the gunk. <S> A pick set is a great assortment of tools to have for all sorts of odd jobs (removing/installing o-rings, for instance). <S> They're very cheap as well - $1.59 as of the time of this answer at Harbor Freight. . <S> In the absence of a pick you can use other tools as a makeshift pick, although it's not very good for them. <S> Eyeglass screwdrivers will work, as will much smaller (eg .5mm) hex wrenches. <S> You might even be able to use a paperclip in a pinch. <A> Last time I had this problem I ended up using pliers+screwdriver to break that washer between cleat and screws. <S> After removing cleat I was able to get screws out with the same pliers. <S> Trying to drill them out was a complete failure for me too. <A> Obviously the destructive method of removal, may damage the small oval shaped plate that distributes the force of the bolts across the cleat as well.
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If you don't have a screw extractor, you can use a dremel tool cutting wheel to put a slit across the cleat bolts and try to remove it with a standard flathead screwdriver. I have yet to try this, but my thought is to install new cleats, then fill the bolt holes with shoe-goo or something similar to prevent the issue. One way is to hammer in an oversized torx bit so that the six points bind up into the six corners, then undo with a lot of inward force and a lot of leverage.
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Should or can I (car) wax my frame? Having spent the whole summer taking a bike apart, painting it and now in the process of building it again, I was thinking about waxing it. I want the finish to last as long as possible, after all, I've spent sooo many hours on this project. Would it help in anyway? Protecting the finish etc. Or could it instead harm the bike? <Q> Using car wax on your frame could certainly help protect it over time, though storing it indoors is much more important so that all of the components are protected from the weather. <S> There are bike specific products like Pedro's Bike Lust <S> but if you don't want to go that direction you should be just fine with any auto wax. <S> In the past I have heard of people using furniture polish as well to give the bike that just out of the shop shine. <S> You will want to avoid the harsher products that contain aggressive abrasives like rubbing compounds, especially if you have carbon portions of your frame, as these will remove the clear-coat and can lead to damage or failure. <A> I've used Turtle Wax on my bikes for years and years with no problems, but any quality polish or wax you prefer should work. <S> I usually wipe the bike down with a soft dampened rag and then wax the frame and metal components. <S> You could probably do the waxing during the winter months early next year and be safe. <A> Use a car paint sealent (polymer based) to protect the paint for the whole season (it lasts up to 5 months without reapplying). <S> Wax or polish will only last a month before it fades away. <S> I recommend AMMONYC skin but any paint sealent will do the job (menzerna or meguiars have good products aswell
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After your new paint has had a few months to cure, you should be able to use car polish or wax on it to protect it.
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Disk brake brakes work poorly after annual maintainance The disk brakes practically don't brake anymore. If I pull the brake lever as hard as I can, the wheel still turns if I push the bike forward. Is this normal? Do they need a "brake in" period? UPDATE: It's a mechanical brake, and the levers are properly adjusted. If I pull the brake lever, I can see the pads pressed against the rotor, but the wheel still turns slowly If I push the bike. This was not happening before. The maintenance was done at a local bike service, I don't know exactly what they did to the brakes, but the rotor seems to be oiled up. <Q> If the pads have oil on them they need replacing. <S> The discs can be cleaned if done properly and carefully. <S> If the LBS did the work, take the bike back and they should put it right. <S> From the sound of it, I would also be looking for another LBS. <S> If they cannot service brakes and keep the oil off they are at probably sloppy - but even the best shops have the odd incident. <S> However, as they returned the bike to you in that condition, it is dangerous, they have let poor work out the door. <S> My future custom with them would be in serious jeopardy..... <A> Two possibilities as I see it. <S> 1) <S> the pads haven't bedded in yet. <S> It takes a good handful of hard stops before a new set of pads start stopping you well. <S> Go out on the street in front of your house and speed up and pull the levers <S> hard a few dozen times. <S> Mechanical disc brake calipers basically act like a screw to press the brake pad against the rotor. <S> This is done by the cable being attached to an arm on the caliper that turns the "screw". <S> One one side of the caliper (or both, depending on your model of brakes) there will be a knob that you can turn that will move the pad in toward the rotor independently of cable tension. <S> Some folks adjust the cable in too far instead of using these knobs to adjust the pads. <S> You can test this by taking your wheel out and pulling the appropriate brake lever. <S> If the lever still stops at nearly the same point that it did when the wheel ws in, then you've found your problem and you need to take the bike back to the shop to have the brakes adjusted properly. <A> It sounds like you haven't adjusted the brakes after you carried out maintenance. <S> You haven't described what you did, but I'm assuming you adjusted the cables from your levers to the pots? <S> If so you probably need to pull them a bit tighter - there will be an adjustment screw at each end. <S> Also read this question on bleeding hydraulic brakes. <S> And as per your update, if you have oil on the rotors, then your brakes will not grip. <S> Follow the link Vorac provided. <A> @jm2 is the correct answer I would say. <S> If there is oil on the pads then braking hard with them will just create heat and melt the surface of the pad, forming a shiny layer. <S> This can be fixed by using white spirit and a little sand paper.
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2)the brakes arent actually properly adjusted and the actuator arm is bottoming out. Clean your disks with white spirit also. It is important that the cable is properly adjusted for this to work.
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Are there any generic hose extensions for frame pumps? I see two kinds of portable frame pumps to carry with me on my riding: Pmps that have a flexible hose that is either integral or pulled out and/or screwed on (e.g. Topeak Road Morph, or Lezyne). The nozzle is at the end of the hose. Pumps that have a nozzle that is right-angle to the pump tube, directly part of the pump itself. The former are generally quite expensive, and the latter ones don't provide good leverage and are prone to bending the valve tip or coming off the valve while pumping, etc. It seems so obvious to me that there should be a simple hose of, say 8 inches long, that would have a nozzle on one end to attach to the bike tube and the other end a fake Schrader or Presta valve head that the bike pump's nozzle would attach to. However, I have not seen them online or in stores. This product, if it exists, would be able to provide a lot of the convenience of those fancier pumps at a fraction of the cost, not to mention it would be a generic way to upgrade existing frame pumps. Of course, the extension should be able to handle the air pressure used for bike tires. Can anyone tell me if they do exist and, if so, where I could get one, or what they are called? <Q> Actually, yes, they do exist and are quite cheap. <S> The old stype frame pump, the very old style was just a stick with a straight shape. <S> At the business end there was a threaded hole in wich you fitted the little hose. <S> It was a arround 6 inches (15 cm) long, and had the propper head for the valve in one end, and in the other ussually had the same thread as the Dunlop Valve. <S> Here is the only picture I could find: <S> These pumps had a receptacle in the handle end, where the hose could be stored. <S> There was a spring inside the telecopic handle, such as to dampen the hit at the end of the stroke, this also alowed you to "compress" the pump a little. <S> The bike frame had a couple of "spikes" pointing at each other alongside some tube of the frame. <S> So to store it <S> you slide the hose inside the handle and inserted the pump between the spikes mentioned before, the pressure from the spring kept the pump in place. <S> That is what you see in the picture, the longest, most shiny tube that is not being held, ia a pump stored in the green bike frame. <S> Those pump hoses are still available, and they look like this: There are hoses threaded for Presta (Or Dunlop <S> , it is the same threading) or Schrader. <S> The end that attaches to the pump usually has dunlop/presta threading, so, if this end is long enough can easilly be used as an extenssion for a modern stick pump. <S> By the way, I managed to get the example picture by typing int the search term "bike pump hose" on eBay. <S> Use the reference picture to locate the type of hose you need. <S> If this option is not accesible for you at a reasonable cost, all the DIY aproaches are valid, but the easiest would involve a replacement hose for(from) a cheap pump. <S> A very easy trick for the hose to pump fitting would be to source a good valve stem from an otherwise unusable inner tube. <S> Use the one you like the most (Schrader or presta). <A> From some quick searching it appears that the only way to do this would be to either make your own or get a hose for a specific brand. <S> Most of the OEM hoses look to be made for floor pump replacements, but perhaps you could cut one and replace the end? <S> Here's a forum thread that might get you started, the links to the pictures are dead but <S> the ideas are sound: DIY pump head extension Highlights of this DIY addon, claimed by its creator ("Fastolfe" user at bentrideronline.com) <S> : takes a split second to connect/disconnect to the inconveniently-placed valve on the Quest's tire lets me read the pressure easily makes connecting the pump to the other side a breeze. <S> You'll need: A couple of feet of 8 mm high-pressure gas hose <S> An 8 mm three-way gas nozzle An 8 mm clip-on Schrader chuck <S> A 0-100 PSI (or 0-10 bar, or whatever range/units you want) pressure gauge with 1/4" threaded connector A 8 mm nozzle to 1/4" female thread adapter Anaerobic thread sealing compound A Schrader valve from an old tube (keep the valve core so you can use the extension as a pressure gauge, without a pump) <S> 6 hose clamps See pictures at the link (or guess) how to put it together: T-shaped tube connections, shortest to the valve, hose clamps go round the pipe, and chuck/valve/nozzles inside the "T" ends. <A> I have seen different lengths of hose for sale. <S> I have a topeak mini track pump which is a combination of both the styles that you mention. <S> I recommend it. <S> It has been useful so far. <S> In my experience pumps tend to wear out way to fast, and are often poorly designed for what you get for the money.
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There will be many different options, most are generic replacements for various types of pumps, but these small hoses usually are sold as "adaptors" so the word "adaptor" may be somewhere in the product name too.
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Can the Tensioner Spring go Bad on a Rear Derailleur? My bike chain has been "skipping", so I've gone through the obvious: I replaced the chain I replaced the smallest cassette cog, which was showing significant wear After my replacements I noticed what the real problem was. Every once in a while, rather than the chain being pulled into the valeys of the rear cog, a chain link land on the tooth, and will not roll into the cog's valley and engage. Each subsequent link of the chain will land on a tooth. When the last engaged link begins to leave the valley, all the disengaged links will be snapped back into engagement by the rear derailleur. What's going on here? Is my rear derailleur's tensioner spring just too old? <Q> The tensioner spring is designed to keep the entire chain under tension, even after it passes the crank. <S> So, the symptom of a too-weak tensioner is slack in the chain between the crank and tensioner. <S> It sounds like the distance between chain links is not quite the same as the distance between valleys in your sprockets. <S> This is not unusual if you replaced a very worn chain (because the sprockets would have worn to match the old chain). <S> You may need to replace the rest of the sprockets in the cassette. <A> Depending on the condition of the entire drivetrain and how many miles/how much use you've put on it, it could be a couple things. <S> As mentioned, it could be a case of worn parts not matching new parts, but I doubt that. <S> More likely is the rear derailleur needing adjustment, as I just had a similar problem. <S> Also check to make sure that the cable tension to the shifter is correct so that it's pulling the chain all the way over and not only half way when you shift. <S> I can't say I've ever heard of a spring getting worn out, but I know they can either break or come loose. <S> If that's the case you can try and repair it <S> but you're probably better off replacing it. <S> Check out this excellent article from BikeRadar about transimission wear as it might save you some frustration: Workshop: <S> Transimission Wear Or this one for rear derailleur adjustment: Park Tool: <S> Rear Derailler Adjustments (derailleur) <A> It sounds like your drivetrain is worn out. <S> You may need to replace the gear changer. <S> In the short term you can experiment with a shorter chain. <S> Have you got the right size chain? <S> Is your cassette 7,8,9 speed? <S> because each takes a different size chain. <A> What you have described is a limit screw or cable tension adjustment issue. <S> If the chain is being guided so that the plates are landing on the cog teeth instead of the rollers then you need to adjust one or the other or both. <S> The replaced sprocket may have caused it to start happening. <S> On the other hand, is it possible that you bent your derailleur hanger? <S> This will knock the aforementioned adjustments out of whack.
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It's also not impossible that the sprockets are worn not quite enough to match the old, worn out chain, yet still worn too much to match the brand new chain. Try adjusting the limit screws on the rear derailleur to make sure that it's shifting all the way to the center of each gear.
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drum brakes and drop handle bars I have sturmey archer xfdd and xrd5. Which brake lever are suitable for these and drop handle bars. The cable is road type with a barrel rather than a nipple. <Q> I can not find anything suggesting that these components require special parts, so it looks like any road bike brake lever should work well. <S> It will be difficult to find a 5 speed brake lever / shifter combo, as most road bikes have many more gears. <A> You will probably want to try to use these with V-Brake compatible drop bar levers (long pull) as opposed to standard drop bar levers used with caliper or canti brakes (short pull). <S> One product that comes to mind is a Tektro RL520. <S> I don't think it's advisable to use with an integrated brake/shifter setup (Shimano STI / SRAM Doubletap Shifters / Campagnolo Ergo Shifters). <S> You may want to consider using bar end or downtube shifters, if you're not using an Internally Geared Hub. <A> Brakes levers come in two different mechanical advantages: http://en.wikipedia.org/wiki/Bicycle_brake#Brake_levers <S> The Sturmey Archer <S> straight bar brake levers are short pull, so you want a short (standard) pull drop bar lever.
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Any drop bar lever that isn't designed for V-brakes (which is almost all of them). If you are replacing the shifter as well, then you should be sure to buy and indexed 5 speed shifter.
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Buying a used higher quality bike vs a lower quality new bike I'm in the market for a new or used bike in the $1000 range and am trying to figure out whether it is worth it to buy a nicer bike with better components if they are already used and worn. For specifics the used bike i'm considering is a specialized tricross comp and it has supposedly been well taken care of and only ridden about 1500 kms. I know i like the tricross frame as i used to have one before it was stolen and the components (shimano 105s) are better than anything i would get in that price range new... But would they still be better or would i probably be replacing them soon? Or does it completely depend on the actual wear and maintenance? Thanks <Q> For the most part, bicycles have terrible resale value, which means that you can usually get a really good deal on a used bike. <S> As for the condition of the components, one can't say without actually seeing them, but quality components should have a much longer life than 1500kms. <S> That said, inspect for obvious signs of wear (there should be almost none), and <S> see if you can find out why the bike is being sold. <S> As PeterH points out, some parts do need to be replaced with greater frequency, such as brake pads and maybe even the chain and rear cassette. <S> Also, check to see if the bike is stolen with the local police or ask the seller for their original invoice / receipt. <A> For sure get a second hand. <S> I've got my Specialized SJ Evo for 2200$ while a new one costs about 5000$, from a guy that works in LBS with a new set of brakes, cassette & chain, and I can't say that I was too much in hunt after it. <S> Just an example for how much more could you get for your money, if you choose a used one. <S> Just be sure to check it very well. <A> I've always bought used bikes <S> but I see it as a trade off: <S> There's something joyous about an older bike. <S> You can get a higher quality frame for the same price. <S> You should also enjoy the process of searching for and weighing up the pros and cons of each bike you see. <S> Its also worth mentioning that an awesome bike stays an awesome bike. <S> My '98 Specialized Stumpjumper (bought in 2001) and my '98 Cannondale R900 (bought in 2005) are still lovely bikes. <S> However the process takes time (searching, collecting, fixing problems). <S> You have to consider how much time you're willing to spend to save yourself the money of the bike. <S> The more expensive the bike the more time that's worth spending.
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Used really is a great way to get the most bike for your buck. Search with a good LED light for cracks in the frame, especially around the welds.
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Knee Pain and Injury I ride a road bike, mainly on flat terrain. About two years ago following a 100k ride I had major pain in the front of my knees, just above the patella. The pain did not subside, was present during the following rides, and I have not been riding (due to a number of unrelated health issues) at all frequently or for any real distance since. This is the third road bike I have owned - and I have been cycling seriously for about 10 years and have previously completed a couple of century rides. I do not ride competitively. I have had two professionals fit and adjust my bike for me - but this was prior to my injury. I now have little faith in their methodology: After all, I wouldn't be injured if the fit was perfect, right? My preferred course of action, to ensure I don't repeat the injury, is to make small adjustments to my bike to find a pain-free riding position: I am currently feeling tweaks in my knees, in the same location, even though I am starting out slowly by only doing 20 to 30K rides. Can someone provide me advice on how to move forward with this? Please let me know if you need more information from me. Thanks <Q> The pain at the top of the kneecap is classical patellofemoral pain syndrome -- the most common knee problem. <S> The most direct treatment is simple strengthening exercises for the secondary muscles supporting the knee joint so that the kneecap remains properly positioned -- such exercises can provide relief in 48 hours or less in some cases. <S> But you should probably consult a sports medicine doc first. <S> (And probably the easiest way to make the condition worse is to lower your seat too low and pedal too slowly, in too high a gear.) <A> I think you need to start shorter than 20-30k. <S> That seems pretty far for someone unaccustomed to riding and with health issues. <S> Your body needs to be ready for a 100k ride and still freak injuries could occur. <S> Also they likely fit you for maximum power or speed rather than comfort or to protect your knees. <S> I am not saying that their fitting method was correct either. <A> The clipless pedals comment needs to be answered. <S> It may be that your feet are at a bad angle compared to your knees. <S> For example, when my knees are pointing straight ahead, my feet stick out at 5-15 degree angles rather than straight ahead. <S> It caused enough problems that I had to get custom Speedplay pedals in spindle lengths long enough to accommodate that splay, and not lock down the float. <S> One thing you can do to check this is sit on a bench that is high/wide enough that you can have your knees right at the edge of the bench and let your feet dangle. <S> See which way your feet point. <S> You could also need shims under one of your cleats to adjust for leg length not being the same, your seat may be causing you to rock, or it simply may be that you jump from a 20-30k normal range up to a century, which is quite a difference.
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(My personal experience has been that some sort of toe clip or clipless pedal arrangement helps this condition, vs plain pedals, though there are probably arrangements that can make it worse.) Fit is important but to assume you will not be injured because your fit is good is wrong.
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How to determine if a decline is too steep for safety? I often find myself confronted by a steep and bumpy bit of hill on the trail, or one or two steps on the path, and end up with three possible results: A) ride down with no trouble (usually) B) step off the bike and walk down (often) C) attempt to ride down and flip over my front tire when it hits the bottom/flat (only once) I realize that this depends on conditions, technique (as in this answer ), and bike (I'm tempted to blame my front shocks for my flip), but it seems like, all other things being equal, there should be a rule of thumb for this sort of thing. So, how steep is too steep? <Q> Ultimately there is no limit to what you can ride beyond your own skill. <S> Many people say "too steep" is a cliff, but some riders just look at that like a drop and ride it anyway. <S> You need to evaluate whether the places you are walking are because you lack the skill to ride them, the confidence to ride them, or improper equipment. <S> Yes, you could theoretically ride an entire downhill track on a fully rigid, carbon XC bike, but wouldn't it be a lot easier on a 8" travel, full-suspension bike? <S> Too far forward on the bike? <S> A big rock/root in the way? <S> Application of too much front brake? <S> Remedy each of these things and you might find yourself riding steeper and steeper hills. <S> So how do you fix it or get better? <S> Practice! <S> Hours in the saddle is the best way to get more confidence riding these types of things. <S> Find a smaller decline and practice shifting your weight back, feathering your brakes, and keeping your eyes scanning for obstacles. <S> Ride with someone <S> Don't underestimate the value of riding with someone better than you. <S> Politely ask them if they could show you how to ride some of things you're struggling with and watch them do it and have them watch you. <S> Speed is your friend <S> I know it seems counter intuitive but like riding over rocks/roots on flat terrain, a little speed goes a long way. <S> Again, practice this, don't just go charging over the edge of a super sketchy hill and hope for the best (although that can be really fun). <S> Lastly, what type of riding do you want to do? <S> A lot of XC trails are relatively tame in regards to steep downhills because the bikes aren't really meant for that. <S> But if you're looking to get into freeriding or downhill you'll need to get comfortable with this. <A> I'm sure my risk calculus is different from the OP's, but I heard a piece of advice some time before from a seasoned dirt rider around my age (mid-40's): "If you can't climb it, don't descend it." <S> Clearly this advice is not applicable to everyone at every time, but in practice I have found this is not bad. <A> This is the conservative answer. <S> I have flipped over the handlebars also. <S> This usually happens when, at high speed and low visibility, the front wheel hits a pit/obstacle too large to overcome (larger than it's radius). <S> So on steep declines I hit the brakes and ride slow, moving my center of gravity back i.e. directly above the rear wheel , being wary of bumps. <S> One article on downhill recommends drawing an imaginary axis through your BB and your center of gravity and keeping that line stable regardless of terrain. <A> The problem (but also beauty) of steeps is that unless you have enough experience with steeps you cannot easily judge whether you can do it or not. <S> So the solution is to see it both from above and from below. <S> If both views scare you then you should probably not do it and in order to gain more experience you need to: <S> practice in steeps smaller in length practice in steeps with smaller angle watch someone at your riding level do that steep first <S> In all cases wear your full face helmet and, if things look really serious, a neck brace may be handy in case of an OTB (over the bars). <S> Ultimately, after practice and if you are really interested in that kind of riding <S> you'll be able to hit stuff such as: http://i.imgur.com/29X0ARs.jpg
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When a hill is too steep to ride very slowly down, then it is too steep for me ( as I do not trust my brakes or my competence to go full-speed down ), and I fall to the side (which is not a problem as I am riding at walking pace) and push down. Looking at the steep section that flipped you over, see if you can find why you flipped.
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Front pannier and child-seat balance I transport my 15 Kg kid on a child-seat. I want to set a pair of panniers. Even if I could put them on a rear rack ( I don't know if I can ), would it be a good idea to choose a front pannier system aiming to balance the weight? I mean to do not have almost everything in the back part of the bike. Without panniers my front wheel often takes off from the ground on slopy rocky paths. Is it worth it, knowing that I will lose some steering comfort with front panniers? <Q> I have ridden with children about that weight on the back; there is no way I would consider adding more weight to the rear of the bike. <S> If you worry about the effect of front panniers on steering, I can only presume you have experience riding uni-cycles if you are considering adding rear panniers. <S> An option to consider would be panniers on the rear and a child seat on the cross bar. <S> This provides many advantages over a child seat on the back, however it requires a largish bike frame - something I did not have. <A> I've ridden "fully loaded", with substantial load in the front panniers. <S> It does affect your steering, but you get used to it after a relatively short time. <S> (And when you take the bags off the front the bike feels like a sports car!) <S> It does require a little more muscle to steer, but in a way steering is actually more stable. <S> You do need to be careful of toe and knee clearance when loading the front. <S> Not generally a difficult problem, but it's bad to discover you have a clearance issue while rounding a corner at 15mph in traffic. <A> If your front wheel is lifting off the ground, then I'd suggest keeping the weight forward as much as possible. <S> Front panniers are the way to go if you can do it. <S> As you say, it spreads the load. <S> We use "low-rider" front panniers on the tandem and often have our 10kg child on the back and this seems pretty comfortable and controllable, but obviously a tandem is quite different in geometry. <S> You could also consider a bar bag if fitting panniers is tricky, but this generally provides less space and <S> the weight & windage is higher up, so possibly less stable.
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In fact I often feel better with panniers front and rear than with either on their own. You'll need a bit more air in your tires to avoid pinch flats with the extra weight (especially the rear).
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How often should I check rear derailleur adjustments? If I remove the (rattling)plastic disc - How often should I check the limit screws on rear derailleur? If the shifter cable tension is less than optimal, would this be a possible cause to drive the chain in between the spokes and the rear cog-set? Excluding the case of debris getting stuck in drive-train; are there any other adjustments besides above two and true-ness of rear wheel that may cause the problem of getting chain between cogs and spokes? Derailleur in question is a Shimano Deore. Update: Details- For mileage, I commute about 110 miles/week. <Q> It's really up to you how often to check your adjustments, but I'd say it's not an "every ride" kind of check, unless you're giving your drivetrain a workout! <S> If there's any damage to the derailleur, hanger, or rear wheel, you may want to start there as well. <S> To specifically address your questions: You should check your limits any time you have a drivetrain issue. <S> That could be poor shifting, dropped chain, or inability to shift. <S> Shifter cable tension should only affect how easily/quickly the derailleur moves. <S> The rear wheel could be out of dish (centered from side-to-side) which might have moved the cassette further in. <S> Readjusting the limit screws should take care of that, but you might still have shifting issues. <S> (I had the same problem this spring) <A> I don't believe these would move without external force but worth checking at every service. <S> No, the upper limit screw should prevent this from happening. <S> Cable tension can be adjusted (most shifters and some RD have barrel adjusters) to optimize shifting between gears. <S> Outer limits are fixed. <S> 3 <S> I can think of: derailleur alignment, is the hanger bent is the wheel in the dropout <S> properly is the derailleur cage bent <A> I wouldn't bother checking until you see a problem, like difficulty shifting onto the biggest or smallest ring/sprocket, or the opposite: shifting off it. <S> When this happens, it is not a "show stopper" problem. <S> You can probably complete your ride, or even just pull over and make the adjustment right there. <S> There is usually a warning that the derailleur is going out of calibration. <S> Before it becomes very difficult to shift to a gear, it first becomes slightly difficult and it progresses from there. <S> Regarding point 3, perhaps you're missing the plastic guard ring which goes between the casette/freehub and the spokes. <S> Which is not to say that this is what prevents slippage, but it does prevent contact between chain and spoke. <S> By the way, one potential problem affecting the front derailleur, or at least some types, is that the entire assembly can rotate around the frame post to which it is clamped. <S> The front and rear derailleurs interact. <S> Notice how it is easier to shift onto the leftmost sprocket when you're on the leftmost ring. <S> So it cannot be ruled out that some rear difficulty is actually connected to a front problem. <S> One last piece of advice, and that is to install a rear derailleur protector , if you don't already have one. <S> This part which installs on your wheel axle, held in place by the wheel lug nut. <S> It extends a curved steel bar over the derailleur which guards it from being knocked around.
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However, there could be a case where too much tension could cause the derailleur to move through the last shift enough to stress past the limit screw, but I think this is unlikely.
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Is vehicular cycling legal in France? I learned to ride in Toronto, where behaviour such as the following is legal : if there is not enough space to share the lane safely with another vehicle, it is legal to ride near the centre of the lane, so that drivers must wait or change lanes to overtake Is this also true in France? I asked a french man (the father of a competitive cyclist) who replied something which implied, "no": that cyclists should keep right at all times, and that although groups ride two-abreast, they return to single-file if a car approaches from behind. I would like to double-check: is it legal, and is it at all customary or is it likely to annoy or cause aggressive driving? Examples of when I might want to use it include: In a town where the road is narrow or lined with parked cars In the country-side, going up a hill with many bends, where it wouldn't IMO be safe for an overtaking car to leave their own lane (which would tempt them to overtake me without leaving much margin) Cars routinely slow down behind tractors when they go up that hill; but when I was driving (a car) I was surprised to see a cyclist hugging the verge as if there was enough room for me to overtake him safely (I didn't think there was and so I didn't). Also, is there any legally-required overtaking margin (for example, "cars must leave a gap of one metre (3 feet) when overtaking a cyclist")? FWIW I understand there is strict liability law in France , which may help, nevertheless I'd like to do whatever it is I should. <Q> The Code de la Route also states the following: <S> En marche normale, tout conducteur doit maintenir son véhicule près du bord droit de la chaussée, <S> autant que le lui permet l'état ou le profil de celle-ci. <S> Which means: <S> In a regular situation, any driver must keep his vehicle close to the right side of the road as much as the state of the road allows it. <S> This part does not specify the nature of the vehicle so bicycles are impacted. <S> The "as much as the state of the road allows it" is a freedom breech that allows you to add good sense to this law: <S> ride on the right, but not too close as to be within reach of an opening door of a parked car! <S> ride on the right, but if the road is narrow enough that you consider overtaking by a car unsafe, prevent it from happening a ride closer to the centre! <S> ride on the right <S> True it might piss the drivers off but ensure your own safety first. <S> The police is not that picky with cyclists and when they're riding on the right half of the right lane, everyone is happy I would think. <A> Note : I finally found the relevant article, so I'm editing my first answer. <S> According to the article R431-7 of the French "Code de la route" : Les conducteurs de cycles à deux roues sans remorque ni side-car ne doivent jamais rouler à plus de deux de front sur la chaussée. <S> Ils doivent se mettre en file <S> simple dès la chute <S> du jour <S> et dans tous les cas où les conditions <S> de la circulation l'exigent, notamment lorsqu'un véhicule voulant les dépasser annonce son approche. <S> Which could be translated as: <S> Drivers of two-wheeled cycles without a trailer or sidecar should never ride more than two abreast on the road. <S> They must drive in single file from nightfall and in all cases where the traffic conditions require it, in particular when a vehicle wanting to overtake them is approaching. <S> It's not really clear if that imply you have to stay on the right of the road, but according to the second paragraph it would make sense to draw this conclusion . <S> However, especially in France, there is the official law and the less-official customs, which can be quite different from each other sometimes. <S> From my personal experience of both living in France and riding a bicycle, staying in the middle of the lane with cars behind you is the surest manner to make the driver loose his patience and start trying to do crazy things, like driving few centimeters close to your back wheel. <S> So I would not advise it. <S> For a full reference of the "Code de la route", you can check the legifrance website . <S> You can get the latest version of the text, and also download a PDF version . <S> It's cross-referenced and you can search on the text. <S> Obviously it's in French :) <A> An update since there has been a modification of the law in 2015 concerning this question. <S> The Article 3 of the Décret n° 2015-808 du 2 juillet 2015 relatif <S> au plan d'actions pour les mobilités actives <S> et au stationnement <S> modifies <S> the Article R. 412-9 of the Code de la route . <S> In particular: 1° Après le troisième alinéa, il est inséré deux alinéas ainsi rédigés : « <S> Un conducteur de cycle peut s'éloigner du bord droit de la chaussée lorsqu'une trajectoire matérialisée pour les cycles, signalisée en application des dispositions de l'article R. 411-25, le permet. <S> « <S> Sur les voies où la <S> vitesse maximale autorisée n'excède pas <S> 50 km/ h, un conducteur de cycle peut s'écarter des véhicules en stationnement sur le bord droit de la chaussée, d'une distance nécessaire à sa sécurité. » <S> ; <S> [And I just noticed that there is no closing guillemet for the first paragraph <S> added... <S> French law.] <S> that is: 1 <S> ° After the third paragraph [of the R. 412-9], the two following paragraphs are added: "Any driver of cycle can move away from the right side of the road when a materialized trajectory for cycles, signalized by applying the provisions of the Article E. 411-25, allows it." <S> "On lanes where the maximum speed allowed is not over 50km/h, any driver of cycle can move away from vehicles parked on the right side of the road, at a distance required for its security" <S> This means, mainly in cities, that when there are cars parked on the right, you are allowed to move to the center of the lane. <S> Notice that the intention is not to prevent cars following you to overtake, but to avoid the doors of the parked cars that can open at any time. <S> As a side note, you might be interested in <S> the full Décret which introduces various provisions in favour of cyclists. <A> As for your second question ( minimum margin for overtaking a bicycle ), indeed there is one: several websites ( one , another ) mention it. <S> From the Code, Article R414-4 (IV) says, Pour effectuer le dépassement <S> , il doit se déporter suffisamment pour ne pas risquer <S> de heurter l'usager qu'il veut dépasser. <S> Il ne doit pas en <S> tout <S> cas s'en <S> approcher latéralement à moins d'un mètre en agglomération <S> et d'un mètre et demi hors <S> agglomération <S> s'il s'agit d'un véhicule à traction animale, d'un engin à deux ou à trois roues, d'un piéton, d'un cavalier ou d'un animal. <S> So the overtaking margin is 1m in urban area and 1m50 outside .
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But keeping a safe distance between your path and the right side of the road, such as around 1 meter, is what most riders do. but if the side of the road is covered by debris, move closer to the centre!
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How do I determine my wheel size Would someone explain wheel sizes. If I am not mistaken, the wheels on my Trek 520 touring bike are 700C. There are no markings, and of course, no documentation of any kind. I assume 700 means 700mm, so 700 / 25.4 = 27.56 inches. If I measure the rim however, its diameter is approximately 25.1 inches. If I buy Continental tires, the size is 28 inch, but I have to buy 27 inch Bontrager tubes. To make matters worse, per this link, tires come in sizes of 26, 27, and 28 inch, and size 700. http://www.schwalbetires.com/bike_tires/road_tires/marathon_420 How can I determine my wheel size, and are these various sizes interchangable. Also, is the 'C' suffix important, and what does it mean? Of course the tires are marked, but I am under the impression (per the dealers comments) that Continental marks their tires differently than everyone else. Also, the tire markings don't help for ordering a new wheel. With so many tire sizes available, how can I know if I am using the correct size. After reading the various answers here, I should explain that my confusion on this matter stemmed from the fact that I used to work as an auto mechanic. In the auto industry, car tires are based on wheel size, 13", 14", 15" etc, and there is no possible way to mount a 15" tire on a 13" rim for example. So when I saw all these different tire sizes, I assumed they all required a different wheel size, but in fact, there is essentially just one wheel diameter for my type of bike, which they refer to as 700C, which is actually 622mm. I also initially assumed that the C referred to the wheel's width, but that isn't true either. The C is apparently just antiquated terminology. So at least in theory, I can mount a 26", 27" 28" or 29" tire on my 700C (622mm) rim. I just need to verify the width of the tire is suitable my wheel width, which is what Sheldon Brown's article explains. Also, I measured my Continental tires, which are marked as 28 inch. They actually measure 27 inches (fully inflated), which must be why my dealer calls their sizing non standard. <Q> I too own a Trek 520 and the bike does indeed come with 700C wheels and has for quite a number of years. <S> The labeling of a 700C tire is somewhat misleading due to historical reasons. <S> 700A, 700B, and 700C tires were all 700mm in diameter. <S> However, the 700C tires were the thickest and the 700A tires were the thinnest. <S> This difference was made up by using a smaller diameter rim for 700C tires and a larger diameter rim for 700A tires. <S> Most tires will have both labels on them. <S> 622 is the size recognized by the International Organization for Standardization, or ISO but 700C has become so common that it is the de facto industry standard label and is how most people will refer to that size. <S> Tire widths are (sort of) an additional complication. <S> This page has a chart showing what widths tires are compatible with what width rims. <S> However, I have run all sorts of widths on my 520, have never worried about rim compatibility, and have never had a problem in that respect. <S> (I have mounted one brand of 700x35 that was big enough to rub on my frame, even though lots of others worked fine.) <S> All of this information and more is available on Sheldon Brown's tire sizing systems page , which is a fascinating read if you want to dork out over tire sizes for a while. <S> The following is in response to your edit: <S> It is not correct that you can mount a 26" or 27" tire on your 622mm rim. <S> 26 <S> " and 27" tires are two different entities and each mounts on a different size rim. <S> A 26" tire mounts on a 599mm rim and a 27" tire mounts on a 630mm rim. <S> Also be wary of 28" tires . <S> While some mount on a 622mm rim, others mount on a 635mm rim. <S> When in doubt, trust the ISO number and stick within the widths on the chart mentioned above. <A> Understand that traditional bicycle wheel sizes have generally referred to the diameter of the tire, not the rim. <S> Thus a 26" wheel will have a diameter of roughly 26 inches with the tire on it and inflated (though the actual diameter is often not reliable enough to size the wheel). <S> And, in particular, 26" wheels (and smaller) have different rim diameters depending on the tire width <S> -- a wider tire will tend to have a smaller rim diameter, so that the overall wheel size comes closer to 26". <S> (Further, a 26 x 1-3/4 tire is not the same size as a 26 x 1.75 tire -- go figure.) <S> 26" tires have ISO sizes from XX/571 to <S> XX/597 (where the XX is replaced with the tire width in mm, and the 571, eg, is the bead circle diameter in mm -- the critical number to match. <S> 700C tires are always XX/622. <S> (And this includes "29-inch" tires that are really 700C tires, only marketed to guys who don't wears spandex shorts.) <S> As to the XX value, that is the "nominal" tire width -- <S> approximately how wide it would be (in mm) <S> when mounted on an "average" rim. <S> Of course, rim width varies (it's stated as the inner width, between the two flanges), and (since tires are flexible in the width direction) <S> it need not be a particular precise value. <S> Rim width should be narrower than the tire width (by roughly a factor of 2), but there are a lot of differing opinions as to how wide/narrow, compared to the tire width. <A> Take a look here . <S> Page five lists 700C as french marking for 28". <S> Be sure to read their preceding discussion, where they explain that correspondences are somewhat arbitrary and it is not impossible for 28" tyres to not fit perfectly on your rims (your dealer was probably correct).
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Nowadays, all tires labeled as 700C mount on a 622mm rim. Originally, tires were sold in sizes based on the outer diameter of the tire. And, while 26" tires vary, 27" tires are (almost) always XX/630. So the only sensible way to match tires to rims is via the ISO sizes (which are tied to the rim size, not the tire).
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Grinding sound on new disc brakes I have a new bike, probably a month old, which has Hayes cx 5 disc brakes. I've noticed that the front brake pad is making a grinding sound when I brake at low to moderate speeds. What could be causing this? The pads that come with these brakes are Semi-Metallic. The rotor bolts are all tight, there is no pad rub when coasting, and the bolts connecting the brake to the fork are tight. <Q> Disc brakes sometimes need to "bed in," which means the pads will wear quickly at first then settle. <S> During this period you can get some pretty awful sounding noises anywhere from screeching and squealing to grinding. <S> BikeRadar has a great workshop article about how to go through this process. <S> Other than that, have you ridden through some wet areas and maybe picked up some dirt? <S> Sanding the pads can help remove any surface dirt/grime and improve braking ability as well. <S> Last option would be that there is something wrong with the pads or the pads are mismatched to the type/brand of brake. <S> You could remove them and take a look and see if the wear pattern looks weird or if there's anything lodged in the pads themselves. <S> It's pretty unlikely, but defective parts do happen. <A> Metallic pads tend to make really ugly sounds at lower speeds. <S> If it is a rather high pitched grindy-squeaky sound that isn't particularly loud, there is no visible damage to the rotor, and there is no perceptible reverberation through the frame or brake lever that coincides with the sound <S> then it is likely normal. <S> With metallic pads, you literally have metal rubbing against metal and this can make some rather nasty sounds. <S> From my experience the sound can be worse with a wavy rotor which is what most manufacturers use now. <A> I have disc brakes to and they screeched a lot when i first bought my bike. <S> all you need to do is to ride your bike around and brake continuously. <S> this will wear down your brake pads so that all the brake residue is on your rotors. <S> this does take time so be patient. <S> this is the exact process with rim brakes ( v brakes)
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Contaminants on the the rotors or pads will cause some extra noise as well. If you're not used to running this type of brake, it may be difficult to form a basis for what sounds normal vs what sounds like trouble, so if you still have doubts I recommend you pay a visit to your local bike shop.
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How can I reduce back pain on a shared bike with poor shock absorbers I ride a bicycle to work every day for several months now.I use a bicycle sharing system that my city offers, and it's very convenient: I don't have to worry about locking the bike or maintenance, I can use the bike only one way etc. However, recently I've started having back pains, and I think it has to do with the fact that the bikes in the sharing system don't have good shock absorbers, and I can feel every bump in the road giving me a strong jolt. Is there a way I can reduce the damage to my back while still using the bike sharing system? <Q> I seriously doubt that it's due to the lack of shocks, unless you have some really bad roads there -- many people ride bikes great distances with no shocks, skinny, stiff tires, and no real springs in the seat. <S> More likely your problem is with your posture -- seat too low, handlebar too low, handlebar too close or too far away, <S> and/or pedals at the wrong angle to the seat. <S> Presumably you can adjust the seat height, so <S> When the seat is at the proper height your knees should be nearly straight at the bottom of your stroke. <S> Next, see if you can adjust the seat forward/backwards. <S> Being too far <S> either direction can cause back problems, so try several positions. <S> You probably can't adjust handlebar height, but if you can, try raising it. <A> By improving your technique. <S> It is possible to have a very comforting ride on rough roads even with a rigid bike (no suspension at all). <S> So, whenever you are seeing roughness on the road ahead you need to do what I've described in https://bicycles.stackexchange.com/a/16315/908 <A> To add to what others have said, I started getting bad upper-back pain on my commuter bike (probably similar to the bike share bikes) on both short and longer rides (a couple miles to 10 miles). <S> For me, the problem was my posture, both on the bike and at work in front of the computer. <S> By hunching over, I was pinching the nerves on the back of my neck which caused transfer pain to my upper back. <S> By trying to keep my back straight and my chin at a 90 degree angle, the problem has disappeared. <S> I also adjusted my bike to have a more upright position <S> so I don't have to crane my neck to look ahead, but I personally believe the most benefit came from improving my posture throughout the day at work so that the bike rides would no longer aggravate the problem. <S> I also try to look up with my eyes rather than my whole head as much as possible. <A> The upright position, typical of shared bikes, are bad for back pain. <S> I doubt you will be able to get into the position shown on the link shared by cherouvim <S> but I would try to transfer more of you weight to the pedals rather than your saddle. <S> Basically try to stand up as much as you can. <S> It will not be easy on those shared bikes but maybe trying will help just enough. <A> This is one of the very rare instances where I might actually recommend a gel saddle cover. <S> They have an elastic fitting and are very easy to put on and take off. <S> If you're stuck with a bike from a share program that you cannot otherwise change, a padded seat cover might actually provide some benefit.
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I would recommend riding a more typical bike when possible as I am not sure this will be enough to relieve your back pain. the first thing to try is to move it a bit higher. I eventually saw a physical therapist who was able to help me to the point where the problem no longer occurs (even on days where I ride ~20 miles).
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Are Shimano R440 road flat bar shifters compatible with a mountain bike front derailleur? The Shimano shifter flat bar series have the same cable pull length than the mountain bike shifters. Is this series compatible with a mountain bike front derailleur, Deore, for example? <Q> There's a great thread here <S> that describes some of this. <S> Here's the meat of it though: <S> Shimano's assertion that you need to use "flat-bar" front derailleurs with "flat-bar" shifters is false. <S> This doesn't make a difference for the rear derailleur (Shimano has standardized the cable pull across all of their shifters), but there's two different cable pulls for the front derailleurs. " <S> Road" front derailleurs require less cable movement than "mountain" front derailleurs for the same amount of lateral cage movement. <S> This has a couple consequences: 1: operating a "mountain" front derailleur with a "road" shifter will result in insufficient cage movement to make the shift. <S> This is rare in the recumbent world. <S> 2: <S> operating a "road" front derailleur with a "mountain" shifter will result in the shifter jamming before the internal ratchet catches, meaning the chain will shift but immediately return to its starting position. <S> In other words, the shift fails. <S> If the shift succeeds, often the shifter will jam at that spot and not allow the shift in the other direction. <S> This is very common in the recumbent world. <S> the longer pull of the "flat-bar" or "mountain" front derailleurs makes for lighter pull at the shifter when using SRAM twist-grip shifters. <S> This can be an advantage for people with slippery hands and/or weaker hands. <S> "Flat-bar" front derailleurs also have cages that better match the larger diameter chainrings typically installed on road bikes. <S> My favorite "flat-bar" front derailleur is the Shimano FD-R443. <S> (This is roughly Sora/Tiagra level parts: cheap, durable, and relatively attractive.) <S> It's since been superceded by the FD-R453, which has a taller inner plate to match newer Shimano cranksets, but I like the FD-R443 for its greater adaptability to different chainring combinations. <S> I've been using the FD-R443 on several bikes, operated by Shimano Deore LX and XTR and SRAM Half-Pipe Attack shifters. <S> It's always worked flawlessly. <S> So no, not really. <S> You might be able to find a combination of gearing, derailleur, and cable pull that will work, but you're probably still better off finding a matching set. <A> Finally, yes! <S> I try these shifters with a Shimano Alivio front derailleur and it works very well. <S> Rear i have a xt with a 11-32 casette and it works well too. <S> If somebody wants to upgrade an old bike with 8 speeds shifters, these is a good oportunity. <S> The Shimano 8 speed r440 road flat bar works with mountain bike front and rear derailleur. <A> I'm not sure people have this worked out. <S> I purchased one of these 443 front derailleurs and discovered with my XT shifters <S> it behaved exactly like a standard road and derailleur. <S> I think what is relevant is that there is a matching Shimano SL-R440 shifter that is flat bar shifter. <S> Based on what I have experienced I have to suggest that it's the shifter in this odd group that does the magic of implementing the correct pull for a road bike derailleur
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When working with Shimano, "flat-bar" shifters are really just mountain-bike shifters in different colors. "Mountain" chainrings are typically smaller, and trying to get a "mountain" front derailleur to work on larger chainrings often involves compromised adjustment or hand-modified cages.
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How fast can my bike go? I have an old mountain bike and want to change to a Pashley style girlie bike. I use my bike to go to the shops, pop to places and go out and about with my dog running along side. I find the seating position of my old bike very uncomfortable in all areas. My concern is, Pashley style bikes only have a max of 7 gears and I currently have 21 gears, of which I only use maybe 4. My speedo shows that I cruise between 5 - 15 mph on my old bike but I'm concerned how fast I can go on a bike with only 7 gears. Is there any way of roughly working this out as I've not found a shop that will let you ride a bike at full speed before you buy it. Thanks in advance, Sarah <Q> There are various gearing calculators available on the web. <S> Here is one of them: http://sheldonbrown.com/gears/ <S> The top possible speed will depend on your gearing, wheel size, and max cadence. <S> Of course, your ability to reach that theoretical top speed will be limited by your own strength and fitness. <A> Step-through bikes are intended expressly for that kind of riding. <S> The only consideration I would give to gearing is whether or not the gearing is LOW enough for the types of hills that you'll encounter. <S> If, for example, you live in Philadelphia there are virtually no hills and a single speed bike is perfectly fine. <S> If you live in Pittsburgh, you'll want consider having at least some gears for climbing those hills. <S> Your candidate bike has 7. <S> That will be plenty of choices. <S> The old Raleigh's traditionally had three speeds <S> and this was/is good enough for all casual urban riding. <A> As a simple measurement, look at the size of the chain ring (the big gear that the pedals attach to). <S> If it's bigger than the biggest one on your current bike, you'll probably be able to go faster. <S> If the chain ring on the new bike is about the same size as the biggest one on your current bike, look at the little gears on the rear wheel. <S> If the smallest one is about the same size as the smallest one on your bike, then then new bike will have about the same top speed. <A> I'm late to the party <S> but, if you only use 4 gears or so, figure out with Sheldon's calculator what gear inches you are using. <S> Chainring teeth x rear sprocket (with wheel size) to figure out what gear inches you are using. <S> Does the Pashly-style 7 speed cover that range? <S> Bueno! <S> Rule of thumb is larger chainring <S> goes faster (pedal speed being equal), but large chainrings, 50, 50+ can be harder on your knees. <S> What is the chainring size that you use now? <S> A midsize ring (in the 40's) can make pedaling easier and easly increase speed by inreasing pedal revolutions. <S> I am running a 46x16 on 27.25 wheels on my single speed, resulting in 77.6 gear inches and 13.9 mph at 60rpm, to 20.8mph <S> should I achieve 90rpm. <S> 77.6 is a large gear where I live with hills, but where I plan on riding, mostly flat, should be Ok. <S> (not my primary ride)
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If the new bike's chain ring is smaller than the one you have now, it will probably be slower, unless it has a much smaller gear on the rear wheel as well. If you're just riding around the city, stopping frequently, and even expecting your dog to run along side, a Pashley bike will go "fast enough".
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How to decode tread patterns? I'm searching for new tires for my MTB, but I'm lost with the many options available, even within a single brand (like Maxxis). Under "Mountain" category alone, Maxxis lists 22 diferent tires, every one with many variants by size, compound and bead, while the only visible difference for me is the tread pattern. I understand that big knobs are better for mud, and small/none ones are better for hard surfaces, but how you translate the tread pattern (beside knob size) into handling characteristics? Can you look at a tread and says what it's good for? Is "climbs and brakes with authority thanks to the opposing parallelogram center tread design" (Maxxis Advantage) just marketing speak or it's for real? <Q> There's not really a science to tread pattern the way you're hoping for. <S> Sure, there are some basics that you've already caught on to. <S> But there are many, perhaps infinitely many, variables involved in how a tire will handle once you get it into the real world. <S> Yes, most of the wording on a brand's web site is just marketing speak. <S> To make things easier on yourself, find someone you know that's done this before or ask this site for a recommended and reliable brand. <S> Once you've got a brand you can trust, use their web site to narrow down your selection and just give some tires a try. <S> You've got to start somewhere. <A> Ask the guys you ride with and also complete strangers you meet on the trail, what they use and why. <S> My guess is <S> 9/10 times it was on the bike already, or it was on special. <S> I have ridden for years, have a range of tires I have tried. <S> Some I have liked better than others, mostly its a trade between speed, traction for braking and acceleration (not my strongest point anyway) and cornering. <S> A tire is a compromise of the following weight cost Straight line performance (one and/or both directions) Cornering (Predictability and maximums) Puncture resistance Add to this <S> the types of terrain being ridden (the list gets bigger) <S> Rock Dirt Sand <S> (soft) Hard pack <S> Pavement <S> Then add Wet <S> Dry <S> If you are a casual weekend warrior like me, you got to the LBS, ask them for a tire for the trails you regularly ride (which they should know) and hope they gave you something half decent. <A> A central uninterrupted patch makes the MTB tire "OK" (efficient) for road use. <S> Big side knobs make road cornering unpredictable (because they bend and reduce stability). <S> As for the intended purpose (offroad biking) it's black magic to me. <S> Generally large spaced out knobs(above picture) are for mud, more dense patterns for hard-packed (they fill up with mud and become slicks in sticky mud), denser big knobs are supposed to break well Just imagine the tire on the bike and what happens(what slides in which direction) <S> when breaking, cornering, accelerating. <S> Rear tires are typically optimised for efficiency, front ones for grip.
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Even so, you're better off just trusting what the manufacturer recommends the tire be used for ( downhill cx/ wet/mud/gravel etc ) rather than spending so much time picking apart the details.
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Are all ready-made wheels sold "cassette compatible" only? I will have to change my wheels on my old trusty late-80s Peugeot (PS28) soon. The rear wheel is mounted with a freewheel-type 6-speed hub (not cassette). I was wondering if all ready-made wheels that you can buy are only cassette compatible (therefore 7-8-9 speeds)? My derailleur is Shimano 105 with mixed friction/indexed mode, mounted on the tube, I suppose it is only designed to support an indexed 6 speed. A LBS told me I could only change the rim of the wheel given the hub is in good condition. What would you suggest would be the best way to approach this? <Q> However if your shop is trying to charge you more then 100$ish dollars for a rebuild, especially on an older hub perhaps consider doing the rebuild yourself. <S> Re/building wheels is not a particularly difficult task with a wheel stand & proper tools all of which are readily available online for reasonable prices. <S> However it can be exceedingly time consuming so consider this aspect <S> as well the reality is that it most likely would take you shop just as long to rebuild the wheel but some times it's more easy to just pay someone. <A> Short answer: <S> NO, there are quite a lot of pre-built wheels made for use on older bikes (or new ones) that come set up for a freewheel rather than a cassette. <S> I see you're in Canada <S> but I still think you should be able to get them from a shop. <S> I would not suggest trying to rebuild your wheel unless you are comfortable doing so as getting the spoke tension and everything dished correctly can be difficult if it's your first time. <S> I will provide a part number for reference, again this is a US based company but they ship to CA as well as a lot of online retailers. <S> If I had to guess this wheel wouldn't cost more than $40 US currency plus a new freewheel if you want one. <S> Point being they are out there, as that was your original question. <S> http://www.jbi.bike/web/checking_product_description.php?part_number=73071 <S> However if you want change rims only that would be a viable option, although if you're on a budget having both redone could be almost as expensive as two ready made wheels, depending on labor costs etc <S> If you go the pre-built route double check the spacing first as the O.L.D. has changed some over the years. <A> I have a similarly old 1975 Peugeot Mixte UO18. <S> I replaced the back wheel with a 700C Dimension Road Rear Wheel with Shimano 2200 hub and put a SRAM <S> PG950 9-speed Cassette <S> (SR-PG950-34) on it. <S> Buying a readymade built wheel was much cheaper than trying to reclaim the old hub. <S> Two things: I had to stretch the frame a bit to fit the 9-speed hub. <S> Our Peugeot's are steel <S> so that's not a problem. <S> My derailleur won't reach to the lowest cog because of frame interference from the seat stay. <S> So instead of a 11-34, it's effectively a 14-34. <S> That's ok. <S> If I really wanted the 11-cog, I'd dremel down the rear seatstay but this is just a commuter bike <S> so I don't really feel the loss.
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If your hub is in good condition & you wish to keep it having the wheel rebuilt is the way to go. There is a US based company called Wheel Master that most shops can get.
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Can I change a 3speed sturmey archer to a derailleur system? Might be daft but can I change an internal hub for a derailleur option. I have an old bike which is slow but I do love it. I want to upgrade my running gear but the "chassis" is still tip-top. I don't want to loose my beloved but am sick of the three speed granddad option. I'm aware that this might not be possible but any help you chaps can offer would be great. <Q> Most three speed internal hub wheels are physically very different in configuration from derailleur (external gear changer) style wheels. <S> Internal hub wheels are fairly symmetrical side to side, but on wheels used on derailleur equipped bikes, the spokes are nearly flat on the gear side and dished on the opposite side. <S> To add a rear derailleur, you would need a complete new rear wheel. <S> There is also the issue of a hanger for the derailleur. <S> Most bikes with internal hubs do not have one. <S> It may be possible to braze one on, but that is complicated. <S> Sometimes three speed hubs are added to bikes that are designed for derailleur systems (to multiply the number of gears) but rarely the other way around. <S> Consider saving the old trustworthy for leisurely rides and investing in a new multispeed bike for more intense activities. <A> Rather than braze on a mount for a derailleur hanger if you don't have one, you could (almost certainly) use an adaptor claw like these: http://sheldonbrown.com/harris/derailers-rear.html <S> (search for "Adaptor claw") <S> http://harriscyclery.net/product/shimano-megarange-tourney-tx-rear-derailleur-with-claw-3189.htm <S> (I'm assuming you have horizontal dropouts, since it's an old three speed bike.) <S> Another option would be to upgrade the hub gears to new hub gears with smaller steps between gears and a wider range than the existing 3 speed, like a Shimano Nexus or Alfine 8 speed or Alfine 11 speed, or even the Rohloff 14 speed. <S> http://sheldonbrown.com/internal-gears.html <A> Still thinking about it? <S> Here's one I did last year, rides like a dream, You will probably need a new (threaded) driver for your SA three speed hub. <S> Available from OldBikeTrader for £15, or from any pre 1951 SA hub. <S> To go with that you want a basic derailleur rear mech and changer(5 speed ideal), pennies from e-bay. <S> You might have to switch to a longer (6 1/4 inch) axle for your hub. <S> Stripping and reassembling SA hubs is not hard as long as you are careful and organised. <S> Excellent video guides on youtube. <S> Photos of finished article here: <S> http://www.flickr.com/photos/31231726@N03/8554241017/ <S> http://www.flickr.com/photos/31231726@N03/8554243339/ Youtube stripdown guide here: <A> bolt-on derailluer hangers, as used on old Schwinns a freewheel wheel in the appropriate size basic friction shifter <S> rock-solid old friction derailleur, e.g. Suntour Vx <A> in the early 60's benlux made a kit to put a 2 sprocket hub on the sturmey archer 3 speed hub that came with everything for about 20 bucks.
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Adding multiple chainrings in the front is a problem because you still need a chain tensioning mechanism, which is usually done by the rear derailleur mechanism. If you have a local bike coop, they're likely to have pretty much all of what you need very cheaply:
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What are these diagonal marks on my innertube? I'm on my second inner-tube in as many weeks and the culprit seems to be the same between them; these diagonal marks on the side around the whole of it—but only on one side (sorry, didn't make a note of what side that was when removing it :( ). Some are shallower, some deeper; the second picture below is the one that was actually leaking. When I took it in to my LBS the guy said I pinched the tube with the tire bead when installing it, but I have a hard time imagining that I somehow managed to pinch the entire tube all along one side, in such a regular pattern (the marks repeat regularly, every 1"), twice in a row. I wouldn't call myself a bike expert, but I have, from time-to-time, replaced tubes; did my front wheel and it's been fine for months. Did I just get lazy/cavalier in my tube installs or is there some other explanation? <Q> One suspects that underinflation played a significant role in this tire failure. <S> If you can see "ripples" in the side of the tire while you ride it, it's way under-inflated. <S> One wall of the tire will tend to fail before the other, based on the rotation and the diagonal cord alignment. <S> The spacing corresponds to where the tire rippled as you rode it -- it repeats in the same location on each rotation since the sidewall gets softer and softer there. <A> That does look like scuff marks from installing it, but I agree you wouldn't find them all the way around. <S> It may be the tube was twisted and when you inflated it, it untwisted and scraped itself against the bead. <S> Try dusting your inner tubes with talcum powder before installing them. <S> The talc will lubricate the tube and allow it to move freely against the tire and rim without scuffing. <A> Do you have a picture of the inside of the wheel you are running them on and the tires you run? <S> I think you'll find the same pattern there. <S> This is probably what is called a pinch flat .
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Those are scuff marks from running the tire flat (or nearly so), and/or from a tire whose sidewall is breaking down.
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How to thread gear cables through outers and end caps? I'm currently putting a bike together with recycled parts and want to get away with not having to purchase a new gear wire. On my first attempt to thread the RD wire I ended up fraying it, cutting off too big a length and having to purchase a replacement. The old FD wire is too short so I want to switch the wire from the right to the left shifter. New cables are cut and 'sealed' in a way that they're easy to thread. For a used wire what is the best way to: cut the wire to prevent fraying? thread the wire through the cable outers and end caps without fraying? It is relatively simple to thread the cable through the entry end cap and outer but even with removing the exit end cap it is difficult to thread through the last cap. <Q> Before I purchased a cable cutter, I found the following method worked acceptably. <S> After determining the cable length make a small mark with a permanent marker. <S> Apply a small drop of superglue to the mark. <S> After the glue dries, cut the cable with a pair of electricians pliers. <S> The glue keeps the strands from unraveling. <S> This still leaves the problem of cutting the outer cable housing cleanly. <S> The pliers do not work to cut the housing. <S> It gets crushed before it cuts. <S> I used an air powered 3" cut off wheel. <S> If you have to purchase either of these tools you are close if not above the cost of a Park Tool or other quality brand cable cutter. <S> Some times the best tool for the job, is the right tool . <A> You just need a good cutter, to cut the cable - it must be strait at the end. <S> Also get attention, that the wire is clean and perfect, have no flattened places, and isn't ripped in some place in the middle. <S> The outer also must be strait (usually you will want to cut the ends of the outer - they like to rip at ends). <S> You also can feel it while inserting the wire into the outer, if it stuck in some place. <S> Don't forget to oil the outer before inserting the wire. <S> This way you always can insert the old rear wire to forward gear or breaks. <A> cut the cable as close to the vise grips with a sharp pair of wire cutters. <S> twist the wire back into shape with a small amount of sticky grease (to help it hold shape). <S> remove the cable outer end caps. <S> twist the wire (in direction of the wire grain) through the first end cap. <S> feed through the length of the cable outer. <S> hold the other end cap up to the light to align and twist as its fed through. <S> Also: check for fraying and fix between each step don't forget to put cable donuts on in the right place $5 isn't much for replacement cables that don't fray! <S> Thanks for all your tips and help!
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The method I've found that works best is: clamp the cable tightly at the desired length with vise grips. On the outer ends (if cut) check, that the iron isn't bent inside, as it will impede the wire.
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I want to remove my front derailleur? I'm new to biking only doing it since the past 3 months. I don't use my front gears much since i'm pretty tall and lower gears means going at a very high cadence for little output. so wondering if i could remove the derailleur. Does this create any problem? <Q> I would fix the derailleur on the gear you prefer (perhaps middle one, to get most of rear gear properly working) as the derailleur don't interfere to leg movement. <S> Take in mind that in few months you can change your mind and start using front gears too. <S> Edit: To remove it you will have to unbar the chain, then open the screw (9mm wrench or 4mm alem depends on derailleur model) on other side of the derailleur. <S> Then return the chain to place. <A> As others have said, sure, it can be removed, but let's look at the pros and cons. <S> Pros: <S> A trivial weight reduction <S> Cons: <S> You lose a whole range of gears intended for climbing <S> You lower the bike's resale value <S> You could reduce weight even more by simply losing a few grams of weight yourself. <S> So unless you live in a place with no significant hills and never plan to sell the bike, it makes no sense to remove it. <S> Just put it on the big chainring and leave it there. <S> The presence of a derailleur costs you nothing. <A> If you're riding on paved surfaces you can solve this by fitting a narrow-wide chainring instead: there are plenty of vendors including Absolute Black, SRAM and Race Face; I've used all of those and they work well. <S> As Alexander suggested you can stay with shiftable chainrings and use the front mech as a rudimentary chain-retention device. <S> To do this you detach and remove the shifting cable and shifter then turn the lower limit screw until the mech is in the desired location. <S> You can completely lock it in position using the upper limit screw as well if you like, but the lower limit screw and the spring should be enough. <S> I wouldn't do it this way as you're unlikely to be able to use the full range of the cassette without the chain rubbing at the front. <S> Maybe it's a good way to find out if you want to go to a single front ring before you pay for the proper chainring.
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If you use the chainrings you have, which are designed to be shiftable, you will find the chain comes off them quite easily if you are in the extreme ends of your rear gears.
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Does the value of an old bicycle depreciate if old tires replace with new ones? I have a 1969 Columbia Newsboy Special that I have had for many years and I have never replaced the tires. Got the bike out of the garage and pumped up the tires to ride and the front tire poped. Rear tire still good. Will replacing both tires depreciate the value of the bike if I ever decide to sell it? <Q> In my opinion the original tires would only matter to a very small segment of the people, and only then if it was considered a "museum piece", and what are the odds of that? <S> You could always remove the tires ( and possibly wheels ), and replace them with a functional set of wheels and tires, and store the originals if you feel the need to keep them around. <S> I've been through the Bicycle Museum of America that has an extensive collection of bicycles from the late 1700's to present. <S> Many of these bicycles have parts that aren't original due to accidents or simply being used up over the years they were ridden, but that certainly doesn't detract from their historic value. <S> Wooden wheels and solid "rubber strips" for "tires" didn't last long on the roads they had in those days. <S> Repairs and replacement parts are a part of the history of that particular bicycle. <A> Like any antique, the closer it is to "original" the more likely the value will increase. <S> However, in the case of many items, there are parts that wear out or decompose over time (rubber, wood, even metal) <S> so they are expected to be replaced. <S> Now, what you could do to maintain value or at least attractiveness to a potential buyer would be to replace the tires with newer versions of the same tire, or try to find ones that look similar to replicate the same look of the entire bike. <A> The tires shouldn't have an impact on the value of the bike. <S> Tires wear out and are discarded.
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If you are concerned, though, and you plan to ride the bike, replace the tires with new ones and keep the old ones somewhere so they don't wear out further. Rubber tires don't last forever and will continue to degrade even if stored in a basement.
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Why did my tire explode? Been running a set of quite nice slicks at 120-140 PSI for a couple of months. Might have done 400-600 km on the bike in that time. Tonight the rear tire exploded while the bike was sitting in my entryway. It's split right along the seam, with a roughly 2 inch long gap. Very loud bang etc. Before I go out and buy another $70 tire, I want to get an idea of what caused this. Some possibilities that I've thought of include: Running the tire at 140 PSI. The tire is rated to that pressure, but maybe this is still too much? Some brief stretches of gravel road (1-2km) I did on it last weekend. The bike seemed fine then however. There is a central heating/cooling vent directly adjacent to where the bike is stored. Perhaps the changes in temperature were enough to damage the tire? The roads in this area are not always very good. Maybe this is just the result of accumulated damage from dozens of minor nicks and bumps? The tire could be defective. Edit: added a picture. Looks like the tube has a ~1cm hole in it. <Q> My guess is cords were damaged on the ride creating a weak spot. <S> Threads held together long enough to get you home <S> and a bit longer, then ripped apart. <S> This kind of delayed and catastrophic failure is not uncommon. <S> Heating vent might have softened them enough to make a difference, but the tire was damaged anyway (assuming warm, not very hot air). <S> More puncture resistant tires may help prevent it in the future, but you cannot prevent it completely. <S> The size of the hole in the tire, and the hole in the tube are irrelevant, its a symptom of the tire failure, not the cause. <S> Once the tire fails, there is nothing stopping the air pressure inside the tube expanding - the tube cannot stop it, it gets pushed though the tire, making that hole bigger and blows up and pops just like a balloon, hence the bang. <S> If you were listening closely, the bang was preceded by a short ripping sound. <A> From the picture it appears that the tire simply failed. <S> Without examining it in person it's hard to tell where the split started, but it appears to have split mostly along the joint between tread and the white sidewall. <S> In general, white sidewalls make the tire weaker, both because the white material is not as durable and because there's a necessary seam between sidewall and tread. <S> Also, the tire likely has some sort of belt under the tread area, and, in such a narrow tire, that can result in fatigue along the edge of the belt. <S> The heating/cooling vent could have been a factor if hot air were blowing directly on one spot on the tire, but seems unlikely if it was cooling air. <S> And, of course, it's always possible that you had cut/bruised the tire at some point <S> and it finally let go. <A> Either you damaged the casing or it was defective to begin with. <S> Once it starts to go it basically zippers open in an instant. <S> The white tread and the vent had nothing to do with the failure, but the 140PSI certainly could have encouraged it. <S> That's not to say it wouldn't have happened eventually at a lower pressure anyway, but to digress slightly, just because your tire says you can run 140PSI in <S> it doesn't mean you should. <S> At some point you are actually slowing yourself down by running higher pressure (unless you're rolling on a glass flat surface, which you're not), and you are most certainly making your ride less comfortable. <S> This gives me the opportunity to post one of my favorite graphs: <S> No reason to be dogmatic about the pressures listed here, but they do give you a good starting point. <S> Don't always pump your tires up to their max pressure. <S> Even if they say they can handle 140psi <S> it doesn't mean you should pump them up that tight. <S> It makes the ride more uncomfortable and it does put more stress on the casing and bead of the tire. <S> If something is going to go wrong with the tire, it's more likely to happen the more air you put in it.
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It may have gotten "bruised" at some point, or the cord may have simply fatigued to the point of failure. Age would be another suspect, but you indicate you've only had the tires a few months, and it would take several years for that to be a factor.
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Can you use a SRAM 10-speed Powerlock with a Shimano chain/drivetrain? I just bought a pair of SRAM Powerlocks for 10-speed chains. The packaging says that they can only be used with SRAM chains. Will anything nasty happen if I use it with a Shimano chain and cassette? <Q> They will work fine together- same if you swap the brands around. <S> This is strictly marketing & legal covering of their own asses. <S> They're all so close in terms of the spacing that interchanging their quick links doesn't make a difference. <S> As an aside, those Wippermann Connex quick links rock. <S> Tool free installation and removal, and it's almost impossible for them to come undone while riding. <A> I don't recommend doing so. <S> And because it was so tight I couldn't get it off again. <S> I had to use a chain breaker and physically destroy the link. <S> Instead, I recommend the KMC quick link, these seem to be much more compatible with Shimano 10speed chains. <S> I've used a bunch of them in the past. <A> Yes you can <S> , I've done it myself. <S> However forget about taking it apart, sram link is ever so slightly smaller thus doesn't have room to be squeezed in and removed. <A> They just take a bit of tugging to "click" into place. <S> I had to put a foot on the pedal and then pull the chain with both hands to get it to lock in.
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If you look at Wippermann Connex Link compatibility they say that the one link is compatible with SRAM, Shimano, and Campy. I've done this many times for myself and for others with no issue and it's common practice amongst bike shops. I put a sram powerlink onto my shimano chain, but it was so tight that the chain was not moving smoothly back and forth.
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How do I stop my rim brakes making a squeaking/squealing sound? I bought a Schwinn Frontier Sport few months ago and started riding happily. After a few weeks my front rim brakes started creaking. It's so annoying in public places. My rear brake doesn't produce any sound but isn't as powerful as the front brake. The retailer says cleaning would solve the front brake's issues and I got it cleaned, but nothing changed. Is there something I can do something myself to fix this? <Q> V-brakes can be hateful and make a lot of sound if they're improperly adjusted- <S> sometimes they're noisy even when they're properly adjusted, especially on braking surfaces that are not machined. <S> You can usually alleviate this with one or more of the following methods. <S> First and foremost, make sure your pads are properly adjusted. <S> This is better demonstrated than described, so check out this youtube video to save yourself a lot of reading. <S> If the link goes down, just google v-brake adjustment . <S> Using anything besides rubbing alcohol may leave a residue and make the problem worse. <S> Toe in the brakes. <S> I found this image which not only illustrates what "toeing in" your brakes is, but shows a nifty little trick to set the gap appropriately: <S> You may need to toe them in more that what this picture is showing if they continue to squeal on you. <A> Also make sure the washers are set correctly. <A> I'll tell you my scenario and what worked for me. <S> I'll list, in chronological order, all the changes I made, because in the end it might have been a combination of changes which fixed the problem and not the final step alone. <S> The bike: a steel hybrid bicycle with v-brakes; single walled rim, with black anodization; new brake pads. <S> Rim condition: <S> the anodization 70% worn, wear groove still deep, rim in good condition. <S> Here are two pictures at different angles: Step 0 (initially) :The pads are toed in slightly as all the instructions on the internet suggest. <S> All mounting bolts tightened using the recommended torque. <S> Rim cleaned with isopropyl alcohol. <S> No play in fork or wheel bearings. <S> Very loud squeal when braking hard (but not as hard as to have the rear wheel lift off). <S> Step 1: <S> Tightened the brake arms and brake pads bolts slightly more. <S> No improvement. <S> Step 2: <S> Removed the wheel, tightened the bearings slightly more (but still allowing smooth turning of the axle), even though there was no play. <S> When I put the wheel back on, I tightened the QR skewer a bit more too. <S> No improvement. <S> Step 3: <S> I slightly sanded the rim and the pads using 600grit sandpaper, then applied a small amount of baby powder on rim and pads. <S> No improvement. <S> Step 4: <S> Added more toe in. <S> The squeal got worse. <S> Step 5: <S> Removed the toe in completely. <S> I set the pads flat on the rim. <S> The squeal was gone entirely. <S> I'm not sure why this worked on this bike. <S> My other bikes with v-brake have the pads toed in slightly, with no squeal at all. <S> I think there are too many variables that influence squeal, like pad material and hardness, pad shape, rim condition, brake arm flexibility, fork flexibility, temperature, humidity, spoke tension and lacing pattern, etc. <S> But the most important one in my experience is pad angle relative to the rim. <S> Maybe someone will shoot a slow motion video, or do a more scientific experiment sometime that will reveal more information.
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Make sure the braking surface of the rim is clean. Use rubbing alcohol and a green scrub pad to scrub off any crud, and then wipe the braking surface off with a clean towel with a dab of alcohol on it.
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Which spokes should I get for an Expresso Coaster Brake with a Velocity Deep V 700c I'm working on my first coaster project with an old 700c frame which I want to make really clean using an Espresso Coaster Hub. http://www.espressowheels.com/griptape.html Rear black coaster brake hub with 32 holes. Includes 16T chrome sprocket, chainstay fittings, nuts and bolts. Hub width: 120mm, axle diameter 3/18". I got the Hub from a friend and I want to make a nice rear wheel with a White Velocity Deep V 700c http://www.velocityusa.com/product/rims/deep-v-622 I don't have experience building custom wheels, so I was wondering if you know which length spokes I should get to have it built. I emailed espresso but haven't heard back yet. I live in the Hague in the Netherlands so any recommendations as to where I should get the wheel built and how much I should pay would be great. Someone recommended I just take the rim and hub to the bike shop and have them pick the spokes and make it rightaway. Is that a better option? <Q> Since you live in the Hague: There is a good chance <S> these guys have experience with espressowheels. <A> There are many sites on the web for calculating spoke lengths. <S> Some of them have pre-filled settings for hubs and wheels, http://leonard.io/edd/ <S> others ask for exact dimensions. <S> The old adage of measure twice and cut once applies here <S> so I would say go for at least 3 sites and check that they tally up! <S> Not forgetting Sheldon Brown's page, http://sheldonbrown.com/wheelbuild.html#length which links to some spreadsheets. <S> Worth a read anyway if you are building your own wheel. <S> By far the simplest though is to take it into your local bike shop and get them to measure up as <S> then you can bring them back when they don't fit. <S> You may want to have a go with some of the online ones then see if the bike shop agrees. <A> We use 268mm spokes for a three cross semi-tangenial spoke pattern wheel on our deep rims (which are similar to Velocity b43 rims), however you're using a 30mm deep rim, so I suggest 280mm spokes.
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For a more general answer: just go to a bike shop with the hub and rim and they'll be able to help you.
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Front derailleur won't spring back to lower gears The front derailleur on my mountainbike sometimes gets stuck in high gears. When this happens and I want to shift down I can nudge it a bit with my foot and it will spring back to the lower gear. I think the spring is still strong enough because just a small nudge is enough. I haven't been fiddling with the two adjuster screws, and -as I said- if I nudge the derailleur after shifting it jumps to the correct position. The issue seems to be the (admittedly pretty large) amount of gunk that has gotten stuck in the derailleur over the years. I tried applying some WD-40 to the moving parts but two small applications have not really helped remove the gunk. Is this still the way to go or is there a better way to get the gunk out without completely removing the derailleur (which I -for now- am too lazy to do). This question deals with a similar problem, but it hasn't moved beyond the diagnosis part (which I have already done I think). [update:] I tried liberally applying WD-40 a few times over the course of a week, including some (aided by hand on the derailleur) shifting after each application. This mostly removed the issue when shifting from 3 to 2, but 2 to 1 remained. Today I went to my local car-cleaning station and applied a high-pressure hose to the derailleur. This removed all the visible gunk. I applied some oil, now shifting is as smooth as can be given the state of my chain and chainrings. <Q> You don't have to remove the FD. <S> WD-40 will not displace mud effectively. <S> I would: use a hose with a decent amount of pressure to remove the gunk, wait for it to dry. <S> (be careful not to spray around the bottom bracket) <S> once the WD-40 has evaporated apply some decent chain lube to the pivots. <S> If this doesn't fix the problem and the cable is moving freely the derailleur may be bent or the spring has lost the required tension. <A> I would clean the derailleur but also replace the shifter cables and housing. <S> In my experience, it is much more likely for the cables to be a little bit stuck than the actual derailleur itself. <A> I had exactly the same problem last year due to running into snowy roads for a week or two. <S> The front derailleur clutch jammed. <S> DO the following: Put your gears to 1:1 position. <S> This is the safest position to start with the optimum cable tension. <S> Also, you will have less chances of messing things up. <S> loosen the joint that is holding the derailleur cable for the front derailleur clutch. <S> This is actually located near where your cassettes are (gear coggs). <S> If you have a thin-brissled brush, it is good. <S> Otherwise, use a cleaning cloth. <S> Clean as thoroughly as possible and make sure all the debris and small granules are not blocking any of the intersections/joints. <S> Tighten the cable back in the joint, ideally and exactly where it was before. <S> Check the up/down shifts for all the gear to ensure that you have got the correct tension level. <S> FUTURE REFERENCE: <S> Depending on how heavy your ride schedule is, you should do it ideally every 4 months or so. <S> In this way, you keep your bike in good condition as well as the safety. <S> You don't want to be in the middle of the traffic and bashing your head wondering why your gear is not shifting down :p <S> I hope this helps.
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Clean the clutch joints and housings properly. apply WD-40 to any moving parts on the derailleur but focus on the pivot points to remove old lube. If you believe you have diagnosed the problem then a clean and a service should be all that is required.
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Should I wait for clear views of the sky before turning on my Garmin Edge GPS? I have a Garmin Edge 200 GPS unit. I commute from the center of Melbourne CBD, where there are many tall buildings and not a good line of sight to satellites. I park in an underground garage, so there isn't an option to turn on the GPS for a few minutes before I set off. I've found through experimentation that if I turn on the GPS as soon as I start riding, it takes longer to get a satellite lock than if I wait until I have clearer views of the sky and then turn it on. So if you consider the first 5 kilometers of the ride, if I turn it on at kilometer 0, it can be 5 kilometers (or even longer) before it gets a lock. But if I turn it on at kilometer 2 (when I'm clear of the tallest buildings), it will get a lock almost immediately. Is there any basis to my experience? Am I better off waiting until I'm a bit clearer, or is there another strategy I can use to try to capture my entire ride? Update: I've experimented with a few things, and have found that the most reliable method seems to be to turn it on and then not move until I get a fix. This works quickly regardless of the buildings around me. It seems that temporarily blocking a satellite by moving makes it take a lot longer. <Q> I don't have any experience with that particular unit, but I do have a Garmin Oregon 450, which is a "hiking" GPS, but I find it works great for cycling. <S> I've found there's 2 important things to getting a lock on satellites. <S> First, as you mention, is a clear view of the sky. <S> The second important thing is don't move. <S> The faster you are moving <S> the more difficult it is for the unit to lock onto a satellite. <S> I can't however, turn it on in my office, where there's quite a bit of concrete around me. <S> I also find it helps if you turn it on in the last place you turned it off. <S> I think the GPS assumes that it's in the same spot <S> it was last time, and tries to lock onto the same satellites. <S> I find if I travel with the unit turned off, it takes longer to get a signal when I do turn it on. <S> I don't know if this is how it actually works, but this is how it seems to work for me. <S> It works better when you're closer to the equator. <S> You're in Melbourne, which isn't close to the equator (-38 degrees latitude, but a little closer than I am up in Canada (45 degrees latitude). <S> I don't think you're far enough that it should be a serious problem. <A> It is probably worth switching on the device as soon as you start heading home, even if you are inside a building. <S> While it may not acquire a lock inside, the signal might be strong enough to download some of the data the device has to acquire, meaning it locks quicker once you reach clearer skies. <S> It's also worth bearing in mind that acquiring a GPS signal involves quite a lot of complicated steps, many of which might impact "lock time" in seemingly random manners.. <S> The GPS signals page on Wikipedia gives a good overview (or, shows how complicated the system is) From wikipedia: <S> If the signal from a satellite is lost while its ephemeris data is being acquired, the receiver must discard that data and start again. <S> This may be causing some of the slowdown if buildings briefly occlude the satellite and it needs to start downloading the ephemeris data from scratch. <A> It's a common problem with GPS that has no wifi or cellular network assistance. <S> In any case you should wait for the GPS to have a lock before you ride. <S> What I usually do is get out on the road, stop, wait for lock then continue riding. <S> You obviously don't want to stop and wait forever. <S> Good thing is while it's trying lock your position, you can see on the display how many satellites it can see and how strong their signals are. <S> So, if just outside your office you see that only there are only three satellites the GPS can see, better to go to a near open space ( <S> e.g. the federation square) and try to get a lock there. <S> Other option is to use a mobile that has a GPS. <S> Mobiles can use wifi and cellular network (which are plenty in CBDs) to lock position quickly. <S> Possible down side is less accuracy on cheap mobiles, but I don't think that's a big issue for commuting where the roads around cities are straight. <S> Mobiles should also be more accurate with tall buildings around where satellites signal are patchy and completely blanketed by wifi and cellular networks.
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The best advice is to turn it on before you ride and wait until it has a lock before you start riding. I've found that I don't really need a view of the sky, as I can turn it on in my house or in my garage, and get a signal no problem. Signal is also affected by where you are on the earth.
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Hydraulic Brake Loud Noise and Vibration I have a shimano br-m446 installed in my MTB, i recently replaced it with new pads, my problem is that it is squealing so bad, with a mild to moderate vibration during braking in downhills. and it's really really annoying. I haven't placed anything on them, i clean my rotors with water and laundry detergent i don't know if that causes the problem. if so what should i do? thanks. <Q> As suggested in the comments, follow the burn in procedure. <S> If that fails, then you can try to reset the caliper alignment (follow the installation instructions or one of the many sites on the internet). <S> If that fails, it may be your pads <S> - what did you have and what did you replace them with? <S> Organics tend to make less noise but don't perform as well or last as long, metallic compounds tend to be better performing material and last longer but are more prone to noise. <A> Some frames are more prone to this than others. <S> It seems to happen the worst with certain hardtail frames. <S> Assuming this is the issue, sometimes the problem will go away as the pads bed in, other times not. <S> If you can determine that you moved from organic to metallic pads and you are through the bed in period, you may want to swap back to organic pads. <A> Try this, Galfer pads, standard pads a pretty grippy and quiet! <S> Burn in. <S> Clean with neat alcohol, available from most DIY shops, at least in Spain for about €2 a litre. <S> Do not contaminate, keep chain and derailleur lubrication well clear. <S> Tight mounting bolts. <S> Hope that helps. <S> MM, Hondon de las Nieves, Spain
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Also clean the disc with a volatile oil solvent such as alcohol or methylated spirits. It's possible that you swapped from organic to metallic pads which may have caused the issue to surface.
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SRAM Rival front derailleur throws chain to the outside, even after professional adjustment TL;DR: if you have a SRAM Rival front derailleur I'd love to know if yours looks "funny" like mine does--it's described in bold . I have a SRAM Rival groupset (from late 2011), including front derailleur/mech, crankset, and brifters. It all works fine except the front derailleur, which is a nightmare. The bike is just under two years old. For the first six or eight months (but that included five months of winter), everything was fine. But one day I shifted from the small to the big ring, and it threw the chain right off the outside. It worked sort of OK much of the time for a few months, but maybe one shift out of ten, it would throw the chain (always to the outside). It started to get worse, and I tried adjusting the cable tension and limit screws, all to no avail. If I adjusted a bit farther down, it would never shift to the small ring. Up a bit and it threw off. I took it to a quite professional cycle shop, and for about $20 they adjusted it. From what I could tell and what they told me, they reoriented the derailleur on the seat tube, moving its rear slightly outward (not sure about height adjustment). It worked fine for a few rides. Then it went back to the way it had been, throwing the chain off. I kept trying to adjust it myself, but it would either not shift up, or it would throw the chain outside. Or it would sometimes shift properly, but only if the rear was around gear 6 (of 10), and not otherwise. Now I have read the SRAM manual, watched videos online, followed all the steps from initial installation (including completely removing the clamp, cleaning, and reinstalling). I moved the derailleur down as far as I could without overlapping the big ring teeth. I carefully adjusted everything. And I'm right back where I started: either it won't shift up, or it throws straight off. There are two things that look strange. First is that the outer plate of the derailleur is not what I would call straight . Rather, it seems to veer inward (toward the bike's centerline) at the back of the cage. That is, the outer plate and inner plate do not appear to be really parallel--but I don't think it was ever any different. The second weird thing is how the chain throws off the outside. It's like the shift is mostly going OK, but only about one link of chain sits where it should, and then the tendency of the chain to go straight when viewed from the top causes it to just run at the same angle from the small ring to the big one and right onto the crank arm. It's sort of hard to describe this, but when I watch closely while shifting, it's hard to see how it's ever going to work well. For a number of reasons I wonder if the derailleur is actually broken. But it looks fine, and the shop I took it to last time (which sadly is now across the world from me, or I'd go back) said it was OK. And there was no crash or anything else to cause it in the first place. I've been fixing my own bikes for two decades. This one has me stuck (and I'm not looking forward to visiting another shop with it, partly because the shops where I live now mostly don't seem that great). Do you think the derailleur is simply broken and needs replacement? How would I even tell? Finally, some people apparently use Shimano 6800/7800 front derailleurs with SRAM shifters. Some of them claim it works much better. Any thoughts on that? Parts are expensive where I live, so I'm a little hesitant to go buy an Ultegra or Dura-Ace part unless I'm pretty sure it will work. <Q> A few things to check <S> : Check the derailleur height to the outer chain ring. <S> Basically, this should be as close as possible without hitting the chainring. <S> Make sure it's well secured to the frame. <S> When you adjust the travel, put the bike into the large chainring, small cog and make sure there's no more than about a 1mm of distance between the outer edge of the chain and outside plate of the derailleur. <S> The only time I've had a chain go over the top of the outer chain ring is when the limit isn't properly set or the outer cage isn't more or less parallel to the chain ring. <S> Remember, to get the derailleur over and outside of the chainring, there has to be enough clearance for the chain to make it. <A> As Rich mentioned by first action would be to check the derailleur height... <S> I kept trying to adjust it myself, but it would either not shift up, or it would throw the chain outside. <S> Or it would sometimes shift properly, but only if the rear was around gear 6 (of 10), and not otherwise. <S> To me, it sounds like the derailleur sits too heigh, or the adjustment of the L-screw has gone wrong. <A> Well, I took it to a local bike shop, and they fixed it, seemingly. <S> I will see how it goes in a few months, but for now it works fairly well. <S> In trying to fix it myself I had moved the derailleur down a bit, so it was exactly 1mm above the big ring. <S> The shop guy moved it back up, and also moved the tail out slightly <S> I think. <S> He also loosened the cable--I didn't think this would make much difference, but according to him the cable was previously too tight and this encouraged the overshooting. <S> And of course he adjusted the high limit screw (that's what he started with too, but that alone was insufficient). <S> So, notes for next time: moving the cage lower didn't help, loosening cable tension <S> slightly may have, and I think making the tail point slightly outward (away from bike centerline) seems viable. <S> Oh, and I think you need a shaman to get these SRAM FDs working perfectly--next time consider a Shimano Ultegra mech instead, because in two decades with four Shimano bikes I've never seen anything so hard to adjust properly.
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Try adjusting it yourself once you checked the height of the derailleur... Not all "pro's" are equally good at gear adjustments: http://www.parktool.com/blog/repair-help/front-derailleur-adjustments Make sure you don't have a bent a tooth on your chain ring.
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What to look for in a Messenger Bag For the purpose of work commuting, what are the features that one should look for in a messenger bag? Size of the bag? Strap configuration? Color/Design? Not looking for specific product recommendations (Unless the product illustrates the concept) but instead want generalizations that can be used to select a bag. <Q> Waterproof. <S> Not with a waterproof cover, but really, really waterproof, like e.g. the Ortlieb Messenger bags. <S> That's the one thing that is paramount if you also want to commute in bad weather. <S> Size depends on what you carry. <S> If it's just some tools, use a saddle bag. <S> If it's a change of clothes, especially shirt and trousers, look for a larger one so you don't have to compress that stuff to much and leave wrinkles. <S> If you also want to buy groceries on the way, as I sometimes do, a larger bag is also good if you don't have or don't want to use a rack. <S> This depends mostly on your size and what kind of bike you ride, i.e. how far bent over you ride. <S> I have the classical rucksack design with shoulder straps, belt and breast strap, because I don't take the pack off hundreds of times a day but enjoy the fact that the pack stays where it's supposed to. <S> (Edit: I ride a converted track frame with my handlebars >20cm below my saddle, so very bent over) Color/design: <S> Whatever you like. <S> I picked mine for visibility, so black and dark colours are out for me, but that's really personal taste. <A> What I keep in my (not messenger) backpack for commuting: <S> Change of clothes (I cycle in shorts & jersey) <S> Shoes (I cycle in SPDs) <S> Spare change in case <S> I forget my wallet Deodorant Mobile Waterproof <S> cover Waterproof cycling jacket Small umbrella (for when I get off the bike) <S> If your work place lets you have lockers or some other storage you can probably keep some of this in your office. <S> I keep a lock, multi tool and 2 spare tubes in a saddle bag as well although my office has a garage so if I'm leaving the bike in public view I take a D-Lock in my bag too. <S> Ask yourself how much of this you need to carry and get a bag that solves those problems. <S> It's easier to get a bag that's too big than one that's too small, I sometimes get milk and/or bread on the way home on occasion, as you don't know what you might end up needing to carry one day. <S> Compartments are useful because you can keep your clothes away from your regular stuff you take to work. <S> Zipped pockets for keeping spare change, mobile phone, etc. <S> separate. <S> I don't feel comfortable wearing a messenger bag while cycling, I find that having only one strap it moves around too much <S> so I ride with a backpack but each to their own. <S> Also remember that the most comfortable position wearing the bag standing up will be hugely different to when you're riding so try to adjust the straps whilst sat on the bike (get someone to hold you & the bike up while you do this!) <S> to get an idea of where is the most comfortable. <S> See also: <S> Why do cyclists prefer messenger bags over backpacks? <A> For size - I've had a Timbuk2 Medium Messenger, but currently get away with a Timbuk2 Catapult. <S> Certainly this manufacturer has a huge range of colours available, and being able to pick a nice one is a bonus - <S> but it's really the design/comfort <S> (they really think about them being for cyclists) and quality of the product that I was interested in. <S> It must be comfortable against you. <S> Some bags have more padding than others between it and you. <S> Similarly, if you sit relatively upright or will use it off the bike, a padded strap might be a good idea. <S> If it has a really waterproof, plasticky body, you will sweat buckets against it. <S> If you intend to take a laptop or tablet, you may want a bag with a dedicated (possibly also padded) section. <S> You may want a zipped up area for various bits and pieces. <S> For bigger bags, you'll definitely want to remove some items from your jersey pockets and place them in the bag. <S> Finally, may want separate sections and stitched pockets for phones, mp3 player, pens, food, wallet, etc. <S> It depends what you take to work and what you leave there. <S> I travel as light as possible - <S> others don't have that choice. <A> I'll add a dissenting opinion. <S> A single strap bag is fine, and the second strap is not required. <S> I've used several, and simply tightening the strap has always been enough to stop it moving around, even at 35 or 40km/h. <S> Naturally, the weather resistance, size, and comfort concerns that the other answers mention are worth considering, but something important and not yet mentioned is to look very carefully at the quality of the stitching on the bag, especially the seems where the strap meets the bag. <S> For instance, many laptop style shoulder bags are not well put together here, and will begin to fray or rip pretty readily, especially if you pack it too full or put too much weight in it. <S> Look for something with quality construction, and pay more if you need to! <S> Having your strap fail (or even just start to fail) is no fun.
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I'd recommend getting a bag which has separable compartments, zipped pockets (inside and out) and is waterproof of comes with a waterproof cover. Strap configuration should be such that you feel comfortable riding with it. For straps, ensure that the bag has a cross-strap (that loops around the other side of your body to the bag), or it will be forever falling off/moving to your front. Water resistance is an important factor, but it depends on how long your commute is, where in the world you live and whether you're a fair-weather cyclist or not ;-).
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Different tire and rim widths front and back - Why? Should I replace one? I just bought a Trek 7.2 hybrid bike on Ebay and got the surprise (didn't read the listing closely!) that the front and back tires and rims are different widths. I am wondering if I should give it a try or spend some money on making the front wheel be the same width of the back. Why would someone have different wheels? Here's the configuration I have: Rims: (Front) Alexrims DA22, (Rear) Matrix 750,Tires: (Front) Vittoria Zaffiro 700 X 25C, (Rear) Bontrager Select Invert 700 X 35. Any thoughts on this would be appreciated. <Q> It is ok to have different width of tires on front and rear wheels, <S> Ihave a thinner tire on rear wheel as the clearance is low and Iwanted to fit a full fender. <S> Why would someone have different wheels? <S> - <S> can(as <S> your's is). <S> Perhaps, if the wheel wasdamaged/stolen the previous owner may have replaced with what isavailable/cheap. <S> If you plan to change the tire size, ensure that the rim can securelyhold whatever width of tire you are about to install and has enoughclearance for fenders/frame. <S> If you bring your bike into local bike shop, they should be able totell you if a certain width will fit your wheel. <S> Just a tip for comfort - 35mm tires will ride a lot smoother as thepressure on 35mm will be approximately half of what <S> 25mm tiresrequires. <A> Wheels don't need to match and neither do tires, unless you're really picky about that sort of thing. <S> Sometimes the wheel is damaged (out of true, bent, cracked, etc) and needs to be replaced. <S> Personally, I ride (mountain bike) with a wider rear tire to run a larger tire for more grip. <S> Fortunately, I bought a wheelset so mine match, but I could just as easily have run my previous front wheel and had a mismatching set. <S> You could also get really granular and look at what spokes, nipples, hubs, and rim strips are the wheels, but having differences in these between front in back won't make the bike un-ridable, it will simply change the way each wheel works. <A> As others have mentioned, there's no problem having different wheels or tires. <S> There are actually some very good reasons to have a larger tire in the back than in the front. <S> Larger tires allow you to run the tire at a lower pressure and gives you a cushier feel. <S> Slimmer tires are lighter, reduce rolling resistance and aerodynamic drag, and give the bike a more nimble feel. <S> Since rear wheel supports more weight, it makes more sense to put a larger tire in the rear. <S> A larger tire. <S> This isn't as much of a concern with the front wheel since it's supporting less weight. <S> Also, your arms absorb an unexpected bump a bit more easily than your butt does. <S> That being the case, you can put a smaller tire up front to make the steering more nimble and reduce weight, rolling resistance, and drag. <S> For all the same reasons mentioned above, it's also relatively common to see rear wheels more stoutly built than their front counterparts. <S> This is most apparent on high-end race bikes, which can have almost twice as many spokes on the rear wheel as they do on the front. <S> The rear wheel spokes are also crossed to give them greater strength while the front are often laced radially without any spokes crossing the others. <A> Unless you have a problem with it, it doesn't make a huge difference to the bike. <S> A narrower front wheel gives more agility in steering, a wider rear wheel more traction in slippery conditions, so it's even a clever combination. <S> The wheels are the same diameter, so it's possible the same tires will fit on both. <S> Width is fiddly, though, so your narrow front and wide back might require different tires, though it is not necessarily the case, as it would be if, say, the front was 26", 650B, or 650A, and the back was a 700C. You can use the same tubes for both. <S> I'd say go with it, and try it out for a while. <S> If you find you really dislike the difference, a replacement wheel shouldn't be too hard to find.
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Other times it's changed to meet a specific need such as wanting a rim that supports a wider tire or a stronger rim if you're riding over tougher terrain. It is quite uncommon for new bikes to have different width of tiresbut used bikes
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Slippage Under Load [New Bike] I got a new bike a three or four weeks ago and have noticed the issue arise this last week or two. When I'm going up a hill (or any heavy load), my gears will slip. I don't think it's moving gears, it just seems to slip a bit. My pedals will lose tension as I hear it slip, then will regain traction about a half a crank later. This happens pretty regularly while pedaling in low gear, maybe once or twice a minute. <Q> It takes a few weeks for the cables to stretch a bit and the derailleurs and springs to seat. <S> This is why most shops want you to return the bike after a month or so to retorque the hardware and readjust the shifters usually for free. <A> I experienced the exact same issue as you when I install fresh cables for my mtb. <S> Follow by re-adjusting the limit screws on the rear d. <S> This solved my skipping issue. <S> Hope this helps. <A> Inspect your chain rings and rear cogs for any visible damage, like missing or rounded teeth. <S> I had this problem with the department store bike I ride now (2008ish Schwinn High Timber). <S> It was slipping on my first few rides around the neighborhood. <S> When I looked it over, I found that I had broken some teeth on the rear (no name) freewheel . <S> I managed to get it replaced via warranty and the new one held up for 1500~2000 miles of multi-use path riding. <S> However I managed to break teeth again when I started commuting and climbing up the hill to work. <S> I replaced it with a Shimano freewheel from the bike shop and haven't had any problems with it since.
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If the bike is three or four weeks old it is most likely due for an initial readjustment. What I did was to tension up the cable for my rear d via the barrel adjuster, making sure to check for correct shifting on all cogs.
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Is it harmful to store a bike in a repair stand when held by the seatpost? I am currently storing my bike in a repair stand where it hangs by the seatpost. I was wondering if this might not be ideal and that the prolonged hanging might put too much stress on the bike and that I should instead store it standing on the floor. Does this way of storing the bike pose any chance of damaging the bike compared to storing it standing? <Q> I don't think that this should be a problem. <A> It might even be better than standing it on the same patch of tyres, if it's not being ridden at all, especially if you're not checking the tyre pressures. <A> Nope, not a problem. <S> The stress on non-moving components comes from repeated cycles of loading and unloading, not from static force. <S> The only thing you'd need to watch out for is over tightening the clamp around the seatpost, although this has nothing to do with the amount of time that it sits. <S> If you clamp it too tight the damage is done in an instant.
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As others have pointed out, keeping the tires unweighted might help lengthen their life in storage, though it should make no difference with the bearings since they're metal on metal with no movement. The force that is transferred through the seatpost to the bike when you sit on it and ride some bumpy road is vastly more than the stress that your bike might get from hanging on the bike stand.
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Which way should a seat post clamp be oriented? I heard somewhere (I don't remember where) once that a seat post clamp should be oriented with the gap at the front of the seat tube, opposite of the gap in the top of the seat tube. The logic behind this was that it supposedly exerts more equal pressure around the entire seatpost. However, I've noticed that bikes off the rack are almost always sold the other way around, with the two gaps on top of each other. Does it really matter? Is one way better than the other? <Q> Typically, for an aluminum post you align the gaps. <S> For a carbon post you turn the clamp 180 degrees from the gap in the seattube to minimize the chance of crimping the seatpost. <S> Some manufacturers have their own recommendations, but they're typically in line with what the aforementioned guidelines. <A> According to a forumer working in bike building industry (SUNN, France), mounting the seat post clamp with its gap on top of the seat tube gap is important to ensure an equal and secure gripping. <A> And less tension means a longer life for your seat post clamp. <S> Now, there's the issue of which way your clamp lever faces if you use a quick release clamp. <S> Most have it facing backwards <S> so it doesn't interfere with clothing and doesn't catch on anything while riding. <S> But, with something this small and utilitarian, I think you can put it any way that keeps your seat post from falling <S> and it's probably OK. <A> My two cents: <S> If you align the gap in the tube with the gap in the clamp, the grip will be much stronger. <S> You'll need less force in the lever to hold the seatpost in place. <S> If you keep them counter-aligned, you'll exert considerably less pressure, and there is a chance that the pressure will be "more evenly" distributed, although I don't "feel" it to be necessarily like this, since it is only the frame itself that actually deforms to grip the seatpost, and I think it tends do deform the same way on both cases (a lot of common-sense here, that would need experimental data to be totally sure). <S> My advice would be: use first option UNLESS you have reasons not to do so. <S> Such reasons could be: sensitive seatpost (carbon fiber, delicate metals), or a tendency from the clamp to leave marks/grooves in the seatpost.
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Aligning the gaps will allow the clamp to compress the tube a little better, therefore reducing the amount of tension needed from the clamp to hold the seat post in.
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Alternative uses for an aluminum MTB frame Any alternative use for old mountain bike tyres and inner tube? So my frame has a large crack near the headtube and I am replacing it. Could I use the frame in any other way? E.g. give it away for recycling, get a few beers with the money make vases from the tubes make shot glasses from the tubes (e.g. with wooden bottoms) beat people with it (!?!? one friend proposed this) Anything more sensible? Maybe I could make some tool or stand out of the material? <Q> Use as a dedicated truing stand. <A> I've been thinking about a similar question for my old bike. <S> This google image search might give some inspiration. <S> More people seem to have the idea to do something with their old bike: Bicycle art at Inspiration green . <S> The church of cycling . <S> Though most re-use seems to focus on the parts that wear out quicker (tires, tubes, chains, sprockets, etc.) <A> A moderately successful lamp. <S> I was too lazy to mount it on a wall. <S> A sling (and a projectile). <S> Maximum range seems to be only 10 meters. <A> How to build something out of a bicycle frame A bike frame can be incorporated into many objects. <S> 1. <S> Have an idea. <S> Start with "I need a [fill in the blank] around the house". <S> Having an actual need for something helps prevent building something that ends up having no use. <S> Possible categories (not a complete list): - furniture - decoration - signage 2. <S> A "normal" [fill in the blank] looks like this - get ideas, Google images is wonderful. <S> 3. <S> I can incorporate a bike frame into [fill in the blank] by cutting it here, adding a bit of pipe here, or bending it there. <S> 4. <S> Sketching your idea(s) on paper will save you much pain later on. <S> To spark some ideas. <S> You could make: A wall lamp <S> A floor lamp <S> Wall art <S> Coffee table <S> Another coffee table <A> Do you need a bike hanging bracket, or even a wall mounted work stand? <S> The front triangle as in the church of cycling lamp image suggests how, and old tubes could be used to give it some grip and prevent it damaging a bike hung from it. <S> Or how about a single wheel bike trailer? <A> They were steel though. <S> I've used chainstays and seat stays as robust tent pegs, for staking down a plastic greenhouse. <S> Worked <S> well once the ends were hammered shut. <S> Dollarwise, recycling is your best bet for aluminium, because its $4 to $15/kilo locally depending on grade and whether you parted all the non-aluminium off. <S> Recently I've been trying to convince myself that I could forge a new aluminium thing from discarded metal, like this guy. <S> Not sure its within my competency level though. <A> As a sort of DIYer, I think that aluminum bits can be interesting for a lot of projects. <S> I'd hacksaw it and extract bits and parts for my creations. <S> For example, the stays can be turned to tool handles; other tubes cut apropiately could serve as shims. <S> The dropouts, specially rear ones can serve as holders for other things, like a toilet paper holder or a couple of coat hangers, key chain hangers, or as beer bottle opener. <S> The whole frame can be mounted on a sturdy base and convert it into a stationary bike. <S> No need to conserve the wheels, just put an old hub in the rear and some rubber bands as resistance. <S> The rear triangle can be converted into a bar stool by installing a cheap but nice and big, plush saddle. <S> Just bolt the rear of the frame to a sturdy base (A couple wood planks would do). <S> The front triangle can be removed or install a small table where the handlebar used to be, thus serving as a workstation if comfortable enough. <S> As you see, possibilities are just too many. <A> Pity <S> it's aluminium - I made a nice set of windchimes from an old steel frame that died, but I don't think aluminium would ring as well. <A> Is there anyone putting up ghost bikes where you live? <S> They might appreciate a donation.
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As others have suggested, parts of the frame can be turned into a desk lamp, a work light holder, or a tool tray holder for your home shop. At our local bike coop, we've welded some old bike frames together to act as a anti-burglary window grille. The whole idea is to think of it as raw material, taking advantage of any shape you can extract from it that lessens the work you'd have to do in order to achieve your desired final product. While not adjustable, the fork could be used for front wheels, back for rear wheels.
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How to compensate broken thread in brake barrel adjuster? On my disc brakes I realized the barrel cable adjuster has its thread broken and most of it is stuck inside the calliper. The picture is not my brake but they are quite similar: the black barrel thread is broken and a part of it is stuck in the silver-y thing on the calliper. I asked the support of the manufacturer and they say the spare part is not sold separately (and I don't know anyway how to remove the broken bit from the calliper). Right now I just live without it, but it is quite neat to fine tune the brake cable length. What are my options? Are there some "standalone" barrels that don't require to be screwed in the calliper? that could maybe be directly inlined in the housing? Should I show it to my LBS and hope him to have some more or less compatible part in his magical drawers? Should I buy a new calliper (<-- yes, that's overkill,.. but well...) <Q> It would require replacing your brake cable housing (and you may want to replace the cable at the same time) but there are brake cables with inline barrel adjusters. <S> In these, the barrel adjuster is usually situated somewhere between the brake lever, and the braze-on at the front of the bike. <S> They look something like this and are sold by themselves, or often included with the cable housing. <S> As your local bike shop <S> and they should be able to get you something that will work. <A> The adjuster on the picture looks like a quite standard adjuster as it is also used on shifters, derailleurs and the like. <A> Often times you can remove the broken piece with a drill bit. <S> Remove the cable from the adjuster. <S> Soak the threaded hole on both sides with penetrating oil,(Liquid Wrench, Sea Foam, PB Blaster) avoid WD-40 or regular oils as they don't do a good job of freeing up frozen fittings. <S> Start with a drill bit slightly smaller than the threaded hole. <S> Drill at a slow speed. <S> If this fails then you will need to get an EZ-Out Screw extractor as @Daniel R Hicks has suggested. <S> If you are not familiar with using a screw extractor be very careful not to break the extractor by over twisting it. <S> This a common problem with the small extractors that you will be using. <S> They are made of very hard steel and cannot be easily drilled out if you break it off in the hole. <S> I am not sure if they are all the same but my Jagwire derailleur inline adjusters have very limited adjustment. <S> They are more of a fine tuner than gross adjustment.
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As you drill through the broken piece the drill bit will often grab the broken piece and screw it out through the opening on the other side. If you have such a part flying around that is no longer needed you could see if you can take the adjuster from there.
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How to properly position foot on flat pedals? I recently replaced my clip-in pedals(SPD) with regular flat pedals on my commuter cycle with the hope to avoid wearing shoes with cleats on my commute. I want to wear my water proof boots to work when cycling. The problem I face is that my feet are not positioned properly, I usually find that one foot is farther or behind the other foot. I considered adding a cage on the flat pedals but I cannot fit my boots in the toe clip. I tried booties on my cleated shoes with clip-in spd pedals, but it is too much effort for commuting, the booties wear out fairly quickly due to frequent stops/walking and I feel that cleated shoes/booties are good for long rides on the weekend. Pedals with SPD on one side and flat on the other still poses the same problem, alignment of foot when using the flat side. I am looking for a solution where I can wear normal shoes/sandals/boots that is weather-appropriate when I am commuting to work. I think a vast majority of cyclists use regular flat pedals/ flat pedals with toe cages. Is there a trick/tip to align both feet properly on pedals or should I give up hope on being able to wear non-cleated shoes and go back to clip-in spd pedals? Or do I just need more practice with flat pedals? Are there other riders who have this problem? I did ride a mountain bike with flat pedals during my high school days but never thought about foot alignment, but back then I had never used clip-in pedals. <Q> This is a mindfulness technique rather than a product, but when riding on flat pedals I consciously focus on keeping the balls of my feet over the pedal spindles. <S> (I also resist the temptation, every time I see someone pushing flat pedals with their heels, to yell out "You're doing it wrong!") <A> I ride flats for everything: city, XC, DH, DJ. <S> Depending on what you want to do you can move your feet appropriately. <S> I find that for XC and commuting types of riding moving my feet back so the balls of my feet are slightly forward of <S> the axle/spindle gives me the best power transfer. <S> If I want more stability I move my feet forward so the arch of my foot is firmly across the spindle <S> so I have more foot on the pedal. <S> Moving your feet inboard (towards the cranks) can increase control and moving outward can give more clearance to your legs. <S> Did you nail a clip-in perfectly on your first few rides? <S> Probably not, same goes for flats <S> , the more you ride that way, the quicker you'll teach your body where the foot goes. <A> James Wilson, who provides mountain bike specific strength training coaching, has made a blog post and video describing how to get a good foot placement on a flat pedal. <S> He has already explained it well, so it's best just to quote him: 3) <S> Foot Placement: <S> This is much different than the foot position where most clipless pedals want to put you, which is with the ball of the foot directly over the axle. <S> However, having the ball of the foot in front of the axle is actually a more natural and, one could argue, better position for your foot. <S> From a functional movement point of view, trying to place the ball of your foot directly on top of the pedal axle is not the best position for your foot to be whether you are on flats or clipless pedals. <S> Driving through the ball of the foot is what you want to do when you are propelling your center of gravity forward – <S> like when running or jumping – <S> but this is not what is happening when we pedal out bikes. <S> When pedaling you are driving the pedals away from you, much like when you squat or deadlift, and that type of leg drive is much better delivered from a more mid-foot position. <S> This more mid-foot position also allows improved recruitment of the hips during the pedal stroke, especially when standing. <A> PIN PEDALS <S> When I abandoned my SPD pedals after breaking my ankle, I had the same problem you faced, my feet slid around on the pedals and I could not keep my feet positioned. <S> As others have mentioned, practice helps and your placement will improve as you consciously work on it about it. <S> Then I recently discovered flat 'pin' pedals and now my feet stay planted where ever I put them. <S> There are a number of different styles with both set screws and 'smooth pins' on the pedal. <S> I purchased a pair of xpedo's for my touring bike and plan to add them to our tandem over the winter. <S> I feel my pedal problems are history with these new pin pedals whether I am riding with biking shoes, walking shoes or my Keen sandals my feet stay put and starting and stopping is effortless. <A> I will point out two things Sheldon Brown has on his site - Keith Bontrager's "Myth of KOPS" and Sheldon has a page on Bicycling in Pain. <S> Short version: The general old guideline is position around the ball of the foot. <S> I prefer to go a little bit towards the arch cause its more comfortable for my geometry. <S> http://sheldonbrown.com/pain.html <S> http://sheldonbrown.com/kops.html <S> Theres also a good thread on rec.bicycles.tech which is a bit long: https://groups.google.com/forum/#!topic/rec.bicycles.tech/nmXPJGOFMjo
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The first thing that you will notice on flat pedals is that your feet naturally go to a mid-foot position where the ball of the foot is placed in front of the pedal axle. As far as getting the same spot every time: practice!
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How do I stop my bike tires from puncturing? I recently bought a specialized Stumpjumper 29 and its only been a few weeks but I've punctured the tire four times already. I think im getting the punctures from the trees and bark on the trail but is there any type of tire that is more puncture resistant that the stock one I have right now? <Q> Its unlikely that the problem is your tire quality. <S> Stump jumpers are not cheap bikes and come with pretty decent tires. <S> Although a Kevlar belted tire might help, its likely to be a waste of money. <S> First up is what you are riding over. <S> Bark, twigs and trees themselves are not going to puncture a MTB tire. <S> Thorns, particularly dry ones, will. <S> Even relatively small thorns (a couple om millimeter) will puncture a tire. <S> If you have punctured and have not removed the offending pointy thing, you will puncture again, this might be what has happened. <S> Are the holes in the same place each time? <S> This is the most likely reason for four in quick succession. <S> Are your punctures one or two holes? <S> If two, you are getting "snake bites" from too low tire pressure - (well covered already, use search).. <S> If you are riding over thorns, then you need to buy thick heavy tires with a Kevlar belt. <S> Light tires puncture easier. <S> Also install thick, heavy tubes. <S> This extra weight wil slow you down, but not as much as fixing punctures does. <S> Consider going tubeless (the sealer also helps seal up puncture holes). <S> You could also ride different trails - I have some locally that I avoid for this reason. <S> It could always be <S> you just had a bad run of it...... <A> Watch what you're riding over . <S> Thorns, glass, and other sharp objects are obviously not your friends. <S> Seems like a no brainer, but it's worth pointing out. <S> Ensure that there's not something sharp embedded in your tire . <S> This is a common problem- <S> you'll run over something that punctures your tire and when you change tube <S> it's flat again not too long after. <S> Sometimes this is due to whatever punctured your tube the first time still being stuck in your tire. <S> Keep your tire pressure up . <S> If you're noticing two holes in about the same spot on the tube that resembles a "snake bite", you're getting what's called punch flats. <S> This happens when the tire and tube compresses sufficiently between the ground and the rim to actually cut the tube. <S> Increasing tire pressure can help alleviate this <S> Let your bike "float" under you . <S> This just comes with practice, but if you get your butt off the saddle in rough stuff and let the bike move underneath you, the impacts aren't as severe <S> and you are once again less likely to suffer pinch flats. <S> As this technique improves you can also decrease your tire pressure if necessary. <S> Go tubeless . <S> This may require a conversion kit, or your existing tires and tubes may be tubeless ready in which case you'd just need valve stems and sealant. <S> If you're unsure about which is the case, ask the folks at the shop you bought it from. <S> Keep in mind you can still go flat <S> but it's less likely. <S> MTB tubeless also limits the max PSI you can use, which shouldn't be a big deal as one of the benefits of tubeless is running lower PSI. <A> Fixing a puncture is not good enough. <S> You also need to find out why the puncture happened in the first place, and solve that problem. <S> Remove the sharp object from the tyre (usually it sticks through and then gets stuck in there) or if it's a pinch flat you need higher air pressure. <S> When replacing the tyre, always fit it so the label lines up with the valve stem. <S> That way if you're repeatedly getting punctures in the same place you will know exactly where on the tyre to search for the offending sharp object that is stuck on the inside, causing repeated punctures. <S> Also check the wheel rim for anything sharp or damaged. <S> But you have a new bike, so that's unlikely unless there was a manufacturing fault. <A> Get rid of the tubes and use Stans no Tubes instead. <S> You'll save a bit of weight where it counts the most, but more importantly the tires will be self sealing. <S> Well worth it <S> , I think most mountain bikers use it <S> and you've probably switched to it by now, but for anyone else that ends up on this page. <S> Here's a demo <A> In addition to all the comments about being careful, Continental that claims to have a puncture resistant tire. <S> ProTection Apex https://www.continental-tires.com/bicycle/technology/mtb/protection-apex <S> I ride road bikes and use Continental Gatorskin on my bike. <S> I have run over glass and not had them puncture. <S> If the ProTection Apex are anything like the Gatorskin, they would be a good puncture resistant tire.
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Chances are your tyre has something sharp on the inside, that is rubbing on the tube while you ride and eventually causing another puncture.
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How do you fix a puncture on tubeless tires? I recently got a new bike with a set of tubeless compatible rims. The stock tires are clinchers with tubes. I'm thinking about putting tubeless on there, but I don't have any experience with them. We have some trees here that drop huge thorns, like nails. They're big enough to go through any tire. When I get the eventual flat, how do I fix the tire? Are there patches? Can you just stick a tube in there? <Q> When putting tubeless tyres on I would definitely recommend that you use a sealant such as Stan's if riding somewhere with thorns. <S> This would be your first level of defence. <S> The sealant would seal up a thorn (or other) hole quickly and painlessly. <S> You can repair a tubeless tyre with a vulcanizing repair kit, but reseating a tubeless on the trail is very difficult. <S> It is virtually impossible to do without 'shop air' (I haven't tried CO2) so carrying a tube is important for any major leaks. <S> You can simply run a tubless tyre with a tube until you get somewhere to properly fix the tyre. <S> Like everything else in the mtb world there are two schools of thought on whether you leave the thorn in or remove it, I would remove it. <S> If you leave it in it plugs the hole <S> but then if you ever do need to put a tube in you <S> risk puncturing that also. <A> Really, you can use the standard vulcanizing tube patch kit as well <S> and it's cheaper. <S> Just don't use the glueless type- <S> they barely fix a tube, let alone a tire. <S> Fixing a tubeless puncture that won't seal is an at home operation, though. <S> You have to clean all the sealant off of the area, let it dry, apply glue, apply the patch, add sealant back and reseat the tire. <S> Reseating the tire without a compressor is a crapshoot- <S> you may get it with a floor pump, you may not. <S> If you're running tubeless you still need to carry a tube with you for that reason. <S> There's basically no good way to fix a tubeless tire trailside. <A> In addition to the other answer they also make plug kits similar to what are used on car tires. <S> If it's a large thorn you can pull it and stick a plug in it, usually without having to re-seat the bead, depending on air loss. <S> I personally like to live dangerously <S> , i ride Mavic UST wheels with UST Maxxis tires and no sealant, no tubes, but i do carry a spare tube in my pack. <S> So far i have yet to flat <S> and I've been riding like that for over a year <S> , 99% all packed trail miles though. <S> So not a big thorn factor on the hard pack.
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There are tubeless tire boots available that you can use to patch a puncture that sealant won't seal.
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Is there a collective name for the non-groupset parts? I would like to estimate the price of a bike if bought in parts. One thing is the frame, that is easy. The front and rear shock can also easily be checked out as individual components. Tires A groupset seems to include: brakes shifters drivetrain BB hubs. Those categories are easy to check for price on the manufacturers sites. However, a few pieces remain: saddle stem bars grips seatpost spokes rims axles pedals. IMHO those peaces constitute a small, but significant fraction of the price of a bike. However, they are so numerous, that checking their prices is tedious, compared e.g. to googling "Alivio groupset" or "Schwalbe Rapid Rob". Is there some easy way, given that I know the prices of all components in the numbered bullet points above, to estimate the price, in parts, roughly, of a bike? <Q> I don't think there is an 'easy' way so it will require a bit of leg work and study to get a good reference. <S> It is unlikely that any manufacturer will offer any of these parts at a higher spec level than that of the groupset. <S> So I would: <S> Choose a few bikes at different spec levels (based on groupset, Acera, Alivio, Deore, SLX, XT and XTR (or equivalent SRAM models)). <S> Jump on to <S> BikePedia and note down what parts each bike has. <S> Use <S> Wiggle or Chain Reaction or similar to price the parts. <S> This will give you some reference as to the price of all the other parts on any bike you are looking at by the groupset. <S> It's also worth noting that: under SLX level most bikes will have generic parts <S> so take an estimate at quality based on materials. <S> bike companies are buying thousands of these items so with economies of scale will actually be paying very little. <S> unless you are buying factory wheels separately you will have to pay for building. <S> bikes cost more to build than buy complete but you get to choose what you want. <A> Usually a gruppo is the parts that make up the drivetrain, and sometimes some of the controls. <S> The rest is add-ons that don't have to match to work together, although this is becoming more true for drivetrains as well. <S> You'll see that higher end parts outside of a group can come in "lines" too. <S> Look at any major manufacturer and you can see this, e.g. RaceFace Atlas. <S> Some companies have partnerships with wheel makers and you might see groups that way, but it's pretty rare. <S> The reason for this is that often times wheels are built with hubs, rims, and spokes from different companies or different brands. <S> Last, but not least, don't forget that a groupset is put together by a brand. <S> They're not going to give you a deal on someone else's stuff if they can't make money on it. <A> There are different build kits available to build up a frame in to a complete bike. <S> Some may or may not include a seatpost and saddle or wheels.
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You could call the collection of groupset and other parts minus the frame and fork a build kit. As far as wheels go, there's not really a standard pairing that's going to allow you view those with anything else.
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How long should pedals last? I use cheap flat pedals, aluminum or plastic. They lasts about a year (1K-2K kms) before dying (cracking noises at each stroke). I don't mind paying US$10 each year, but it hurts my eco-heart: I want to recicle, to repair and not pollute the Earth. How long should pedals last? Do serviceable pedals last longer? May I try to repair non-serviceable ones? <Q> Increase your budget until you can afford second hand pedals with cup-and-cone bearings, then spend a few bucks servicing them. <S> DMR's V8 and V12 models are very popular and have been the same for years. <S> The V12 typically has better seals and lighter materials than the V8, but both are serviceable. <S> Here's a guide on servicing the DMR V8: <S> http://steveukmtb.wordpress.com/dmr-v8-pedal-overhaul-cup-and-cone/ <S> I got Wellgo's V8 clones via eBay for 7GBP delivered (about 10USD?). <S> I don't know if they're the same internally <S> but they might be an option if you cant get pre-loved DMRs. <A> I used to have the same problem. <S> My pedals would last about 2000 miles, then the inner bearing would fail, which is what makes the cracking noises you refer to. <S> I finally raised the devil with my Trek dealer about the cheap parts he was selling me, and he came up with a set of pedals made by VP Components. <S> There are 2 differences between these pedals and the ones I was using. <S> First, the inner bearing on this pedal is a brass bushing, not a ball bearing. <S> Second, this pedal has a dirt/water seal to protect the inner bearing. <S> I have been using these for at least 15,000 miles now, and they are still as good as new, and they didn't cost any more than the cheap pedals. <S> If you buy a new pedal, turn the pedal's axel. <S> It should turn with perfect smoothness. <A> If they're not made very well <S> and/or you expose them to harsh weather or dirt they could be destroyed the first time you ride them. <S> If you buy good ones and keep them properly greased/etc they should never need replacing. <A> Buy better pedals. <S> I bought a kind of hybrid - clipless on one side, platform on the other, fully metal - and they've lasted me 4300 km this year with no visible damage other than some scratches. <S> Judging by their state, I think they'll last me at least 2-3 more years of intense use. <S> And they cost the equivalent of $50 dollars, which really isn't that much if you think about it.
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If you feel any sort of catching, it is using very cheap ball bearings, and it isn't worth installing on your bike. Properly made pedals that are looked after should last longer than the bike they're attached to.
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Treacherous ride - top half of fork points backwards, but the bottom points forward I have a Kent Glendale with dual front suspension. The top half of the fork is turned around so the right shock was installed into the left stanchion and vice-versa. and I cannot figure out how to remove the lower half of the fork. There are no screws on the outside, just a rubber stopper at the top of each stanchion tube and a nylon split washer at each joint. Looking down through the tubes, it's just a black hole for several inches. <Q> After a little Google research of this bike, you can see that the fork is assembled correctly. <S> What's going on is that the crown (the part the stanchions attach to) is bent/twisted or the steer tube (the tube that runs through to the handlebars) is bent. <S> Either way, you're going to need some mechanic work or a new fork. <A> It looks like this bike has been run into the read of a stopped car. <S> It may be cracked at the top of the form blades, at the crown. <S> REPLACE! <A> That for is not mis-assembled, it is bent. <S> It's damaged and probably dangerous to ride. <S> Throw it away and get a new one. <S> It will likely cost less than $100 installed. <S> Small price to pay for your safety.
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On a side note, you can probably remove the stanchions from the crown, but judging by the amount of rust in your pictures, they're probably fairly stuck by now.
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how do i stop my Formula disk brakes from squealing I have seen a number of posts about stopping discs from squealing, but mine don't always squeal, when the squealing starts it doesn't stop (as if something has worn off) and it's not worn out pads. Is it true that some makes and models of discs just squeal? If so, time to change brake manufacturer? Is it true that different compound pads will make the squealing stop? <Q> Short answer is don't throw out you brakes just yet and a different material MIGHT make the squealing stop. <S> What you are experiencing is quite typical. <S> Mine are really bad sometimes if they are wet or have dust on them. <S> A few max effort stops fixes it. <S> Steps to address, in a rough order based on cost and hassle factor, and no guarantee of success... <S> Find a nice steep down hill and do a half dozen or more max effort stops from the fastest speed to can get up to. <S> (safety warning bla bla bla). <S> If that does not work, repeat after emptying you water bottle over the disc. <S> Realign <S> the brake calipers Clean the discs with meths/white petrol etc <S> if you can be bothered trying it, 'burn' the pads polish the discs and pads with a very fine (400 or 600) wet and dry sand <S> paper <S> Replace the pads with Organic ones. <S> Replace the disc rotors <S> I'm out of suggestion, buy some ear plugs...... <A> So you might want to check everything <S> is nice and tight. <S> I had a squeal for a few months out of the blue, then happened to be caught in an enormous downpour, riding through deep and dirty water puddles. <S> The next day (and since) no squeal :) <A> It fixes it 9 times out of 10.
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My understanding is squealing can also be caused by micro vibrations, and not necessarily in the brake system itself, for example, due to slightly loose forks. When mine squeal I remove the pads, buff with some wet and dry, put them back in, and re-center the calipers.
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When Should I replace the rotors on disk brakes? I've probably done about 20k on the rotors I bought the bike with. They still work fine, but are visibly worn and slightly grooved from me not replacing the pads soon enough a few times. How do I know when it's time to get new rotors (apart from by finding out the hard way, of course)? <Q> Normally the manufacturer of the brakes gives some minimum value for the rotor thickness. <S> For higher prized brakes they often even provide some gauge that lets you easily check if the rotor is still thick enough. <S> Typically the minimum thickness might be somewhere below 2mm <S> (I believe to remember that the absolute minimum for Magura discs should be 1.7 or 1.8 mm). <S> But as said, this should be an information that should be in the manual fo your brakes. <A> In my 14 years cycling career only once I had to replace rotor due to wear. <S> And that rotor was 6 years old and used for heavy downhill riding in all conditions. <S> I've gone through a lot of pads on that rotor (like 20-30 pairs). <S> And only when I could actually feel with my fingers the groove on the surface, I replaced it. <S> Also it started eating pads like mad - uneven breaking surface wore pads much quicker. <S> I'd say rotors is something you would not replace quite often. <S> And rotors would not fail on you like <S> a worn-out rims - rotors won't split easily. <A> Shimano recommends that its rotors, which start out 1.8mm thick, should be replaced when the braking surface has been reduced to 1.5mm. <S> Credit https://road.cc/content/feature/when-should-you-get-new-disc-brake-rotors-257623
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So for a sake of measurements, 30% thickness reduction would be a good indication to replace the poor thing.
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How to prevent wrist pain on road bikes? When I started bike-commuting with my road bike I developed chronic pain in my wrists. It probably took a year to go away, and now I have been free of complaints for several years. My wife just started bike-commuting with her road bike and she started to complain about painful wrists as well. I assume this has to do with holding weak wrists at an angle for an extended period of time . I was thinking about pointing her handlebars downward a bit, but am worried that she will slide off the grips mounted to the top of the handle bar (I don't know what those are called...) when she rides with her hands above the bar and has to brake abruptly. Something else we were thinking about trying is wrapping her wrists with elastic bandages, but we weren't sure if we were going to exacerbate or at least prolong the problem, since she would probably use her wrist muscles less. <Q> I switched bikes a year ago, and I noticed on my rides (50km - 70km) <S> at the time that I had some numbness / cramp / pain in my hands and wrists, it was so bad on some rides that I need two hands to change gear. <S> The bike had slightly different geometry than my previous road bike. <S> I now ride frequently 100km and even up to 180km with little or no pain. <S> Here's what I did and what changed: 1) <S> I took the bike to my LBS and asked them if there was something they could do. <S> The adjusted the shifters outwards so that I wasn't stretching so far to change gear. <S> 2) Good gloves with good padding in the right place, to prevent putting too much pressure on the nerves that run through your palm. <S> 3) rotating hand position, on a road bike you have 3 (or possibly more ) hand positions. <S> Use them. <S> They are not always practical in every situation but you can often switch from the drops to the hoods or vice versa on the flat, and the hood to the tops or vice versa on climbs. <S> This change in position will help with cramping. <S> 4) finger clenches and stretches. <S> As soon as I start to feel my wrists or fingers getting tired <S> 5) Hold the handle bars loosely. <S> My main problem was that I was gripping the handlebars way too tightly. <S> If you relax your grip to the loosest possible you will reduce cramp and reduce the effect of vibrations from small bumps and rough road surfaces. <S> This is especially important for long fast downhills. <S> I would grip on for dear life (doing about 60kmph - 75kmph) <S> Also when braking on the down hills its better to pump the brakes rather that keep them on the whole time. <S> All this takes practice <S> and I am sure that the muscles in my wrists got used to the abuse they were getting too. <S> In the end I am fine. <A> Seems like you need a bike fitting for your wife. <S> Depending on the length of her ride (probably 2-5 miles for people not used to longer riding), she may need to work up to riding the commuting length instead of just jumping to the full commute. <S> Another thing is some bikes have very aggressive geometries for racing - you may just need a less aggressive geometry (some cyclocross bikes, touring bikes, etc.) or switching to something like a flat bar road bike (hybrid) or an old mountain bike (I prefer flat/riser bars for commuting under 10 miles, and a more upright geometry). <S> Sheldon Brown has a bit more things which may be useful, so I defer to him: http://sheldonbrown.com/pain.html <A> With drop bars you don't have a lot of options. <S> Make sure she's comfortable riding on the hoods because that's IME the best position for wrist support. <S> Often women have relatively shorter upper bodies than men of the same height, so on a bike that's the right height they're stretched forward. <S> So she may be spending more time on the drops and flats than you expect, which will not help with wrist pain. <S> If she has or can fit flat bars, try bar grips with wrist support. <S> The expensive-but-worth- <S> it option is Ergon, who make a range of grips that are more or less all the same shape: http://www.ergon-bike.com/us/en/product/gp2 <S> This stype of grip locks on to the handlebar (to stop it rotating) and supports the palm of your hand significantly more than a round grip does. <S> There are cheaper versions of these around and most bikes shops should have a set. <S> I found they did wonders for my comfort, and the silly-looking mini bar ends are great in traffic - they're just big enough that if my handlebar hits something they keep my fingers from getting crushed. <S> One slightly crazy option <S> if you are locked into drop bars would be a flat bar with "drop bar ends". <S> That would let you mount both ergon-style wrist supports and your existing drop bar brake/shifter setup. <A> Most common problem for wrist or shoulder pain is the saddle angle. <S> The shoulders, arms, hands, and wrists need to hold your weight if the saddle points downwards. <S> Hence, the saddle needs to be horizontally aligned. <S> Here is a good manual on how to adjust the saddle: https://www.canyon.com/_en/supportcenter/article.html?supportcenter_categories_id=10&supportcenter_articles_id=148&type=rennrad <A> I would add to the above answers that wrist-wrapping is only a palliative; it may relieve the pain temporarily, but almost certainly won't solve the underlying problem. <S> The pain will just come back, and the damage will worsen and become harder to heal. <S> I agree with Batman's suggestion of a bike fitting. <S> Alternative handlebar designs (bullhorns, trekking bars) might also help.
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I'd suggest checking the saddle angle (it may be too downward), raising the handlebars if possible (this may or may not be possible), and checking her posture. clearly you want a harder grip as even small bumps can be dangerous, but squeezing very hard on the handlebars will give you cramp in no time at all. A good bike fit may be the only solution you need. I take one hand at a time off the handlebars (where it is safe to do so) and clench and stretch my fingers 5-10 times.
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Where can I find Shimano jockey wheels? I have a Shimano RD-M510 rear derailleur that needs both jockey wheels replaced. Were can I find them for this older unit?Jerry <Q> The compatible part is SHIMANO RD 5700 and the part number is 5XH9812. <S> The set come as a pair and is available at a number of places such as Chain Reaction Cycles and Wiggle . <S> The only thing to ensure if using generics is that they are the right chain size. <A> Search for "Tacx Jockey Wheels" in your favourite online bike shop. <S> They come with cartridge bearings which work great before you use them in muddy conditions (MTB, CX). <S> After these heavy conditions I have found then to lock up. <S> In case of a road bike, I would totally reccomend them, the difference when spinngin pedals backwards is noticable. <A> Your LBS should also be able to get them if they don't stock them. <S> They may be called derailleur pulleys or jockey wheels. <S> You want to measure the wheel width and tooth count if you are using something other than an exact replacement from Shimano. <S> The top and bottom wheels are generally not interchangeable so make sure you order the correct ones if they are available as separate pieces. <A> Shimano provides the following parts list for the RD-M510 <S> ( http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/RD/EV-RD-M510-1896_v1_m56577569830609142.pdf ): Y-5UN 98060 Guide Pulley Y-5UN 98070 <S> Tension Pulley <S> You can take this sheet to your LBS and get them to order it for you.
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Tacx manufactures some great jockey wheels which are compatible with Shimano/Sram/Campagnolo products. Most on line retailers Chainreaction cycles, BlueSky cycles, Excel Sports carry them.
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Best way to patch road bike tubes I've scoured the internet for this answer, as I recently just tried to repair a tube on my Purefix fixed-gear bike which I assume uses tires and tubes similar to road bikes, as the tire size is 700cx28. Anywho, the patch pinched the tube and was no longer usable. I used the pre-glued ones, but the problem seemed to be that the patch pinched the tube. Does the type of patch (pre-glued, non-pre-glued) matter a ton? Should I apply patch to a partially inflated tube or deflated tube? Does the tire-liner stuff really work in preventing flats? Are my tires to blame for all my flats? This is my first time on a bike that isn't a mountain bike, and I've had 3 flats now in 2 months and I haven't been able to patch them. Thanks for all the info guys and gals! <Q> When I make a repair, I also do the following extra steps, to make sure that the patch holds. <S> I have never had a patch come off/leak when using this technique. <S> Use a little bit of sandpaper to remove any ridges on the area to be patched, such as a manufacturing join. <S> Especially so if you have sanded the area. <S> I would usually use methalyated spirits and a lint free cloth of some sort. <S> Once the patch is applied, apply some chalk dust to the area, this makes sure that the solution/glue does not bond to anything else. <A> Does the type of patch (pre-glued, non-pre-glued) matter a ton? <S> Based on my experience I have more confidence in the non-pre-glued ones, but I've used both types succesfully. <S> Should I apply patch to a partially inflated tube or deflated tube? <S> I always apply the patch to a deflated tube. <S> Since you have a leak, inflating and then applying the patch before it deflates again just leads to sloppy work and possibly airbubbles between tube and patch. <S> Does the tire-liner stuff really work in preventing flats? <S> I don't think so. <S> (see also batman's answer). <S> Are my tires to blame for all my flats? <S> Possibly, if they are really very thin, or there are sharp bits sticking through to the inside (you do check for that when fixing the tube I assume). <S> However, with frequent leaks the first suspect I turn to is tire pressure. <S> You should properly inflate your tires, this prevents more leaks then any specific tire can. <S> 4 bar for bigger MTB-style or hybrid bicycle tires, upto 8 bar for thin road-bike tires. <S> Not enough pressure leads to frequent pinch-flats. <A> Typically the old style patch kits work better than the pre glued ones, but properly applied ones should hold up. <S> Follow the directions in the patch kit to apply it properly. <S> You need rim tape, but not a tire liner (check to see its in good condition). <S> Sheldon Brown says tire liners can cause more flats: http://sheldonbrown.com/flats.html Check for things on the inside of the tire (or outside) or canvas showing. <S> Those can cause flats, but what is the shape of the damage to the tube?
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Clean the area to be patched, this makes the glue/solution adhere better to the tube.
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Cyclocross racing with fixed gear road bike with cross tires I would like to take part in three local cyclocross races in the coming weeks but have a bike dilemma: Should I convert my track frame to a new fork and put one cantilever brake on it and change the tyres, or change the tyres on my Kona road bike (I checked to be sure that there is enough clearance for cross tyres) and race with road bike style calipers but increase the calipers clearance to the rims? At the moment putting cross tyres on my road bike is the cheapest but no one uses calipers so I assume it's a stupid idea. But is converting the track bike silly too? All races are flat, btw. <Q> Neither option is a good idea:If you use caliper brakes for the cross race, they can easily be filled with mud and became useless. <S> If you go with fixie you'll be very slow on steep uphills and it will be dangerous to downhill without a freewheel. <S> But you can try if it will be very simple race :) <A> I'd have to say both sound like a pretty bad idea, with the fixie hard to mount/dismount and control in a cyclocross type situation. <S> Sheldon brown does mention someone whose done it ( http://sheldonbrown.com/singlecross.html ), but it seems like something you may want to do after considerable practice with the course in a non-fixie. <S> You wouldn't be the first person to try it though ( http://www.fixedgeargallery.com/interviews/mike_clark/ ). <S> As for a road bike, I'm not sure you want to put your road bike through a cross race. <S> If its not too muddy and your road bike is set up with a stable geometry, you may come out alright with the road bike. <S> I'd say if you have downtube shifters though, you will need to move to barend shifters or brifters or retroshift or something (you didn't say which Kona bike you had - they currently do a wide range of them <S> and I have seen a Honky Tonk with downtube shifters for some reason...). <S> My suggestion is to pick up an old rigid mountain bike (say, a 80s-90s specialized rockhopper/hardrock) which should be pretty cheap and easy to come by, put some tires (look at some cross tires you were considering in 700c and find something which you think will be similar in 26) and decent brake pads and go for it. <S> Lots of people use mountain bikes for beginner cross, and I think this option will probably keep your road bike in better condition and not be too different in price from the first option depending on which rigid mountain bike you start with. <A> 30 years ago when "long reach" calipers were standard, it was fairly common to use caliper brake bikes for cross. <S> It's not ideal, but it will work as long as the course isn't super muddy. <S> However, most road frames these days will only work with at most a minimal tread 28mm tire. <S> There aren't many cross tires that would fit in "standard reach" brakes. <S> Even if you go with a fixed gear setup, I think you really want two brakes for riding dirt. <S> By the time you convert the track bike, you're pretty close to what a used rigid MTB would cost. <S> I have not raced cross with a fixed gear, but I've done a fair bit of dirt riding on a fixed gear ( see http://www.63xc.com/ ) <S> and you really need a back brake that doesn't skid.
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If your road bike will fit a cross tire, then I'd just use that.
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Plastic screw with ripped-off head stuck in the frame So I attempted using a couple of shitty plastic screws to attach an air pump to the water bottle mounting holes in the frame. I was using a long-arm torque wrench and the head of one of the screws just came off, leaving the body inside. I need those threaded holes in order to install the pump! Thinking of burning the screw body with a soldering iron and then forcing a steel screw in, to clean the thread. Would this be a good idea? Maybe drilling would do better? Anything to be careful about? <Q> As the comments have stated, here's your options: <S> Drill : Use successively larger drill bits until most of the screw is gone. <S> Drill and extract <S> : Drill a spot large enough to put something in the middle and pull it out. <S> Screw/Nail Extract : Lightly tap a nail or smaller screw into it and then try to unscrew the stuck body. <S> Melt it <S> : Not really recommended but you could do it. <S> Be prepared to retap the threads if things go awry. <S> Note, these are not in any order and some can be tried before others. <A> You could try heating up a screwdriver and pushing that into the screw, then (after everything has had a chance to cool down) using it to turn the screw out. <S> Start gently and increase the heat until it works. <A> The feeling is comparable to those metal bolts with rubber seal to prevent vibration. <S> Consequently, when I was screwing the bolt in, there was no increase in the feedback torque - it was moderately difficult to screw the bolt in, up until the head broke off. <S> So, firstly I tried to burn a slot in the body of the screw with a heated screwdriver. <S> I got it several millimeters deep, but when I attempted to turn, half of the screw broke off. <S> Next I tried drilling with a dremmel. <S> The bolt is in the bottom of the front triangle, so even though I used a flexible arm (like the ones at the dentist's), I was unable to attack the screw co-axially and the drill bit constantly hit against the aluminum frame. <S> Bought a cheap, thin-nose, 30W iron and managed to remove a lot of material. <S> This was the most successful method so far ... almost. <S> Having done everything possible, I inserted a steel screw and tried to chase the thread with it. <S> To my disappointment, it didn't work. <S> The "nipple" at the frame began rotating, with respect to the frame. <S> The bolt become stuck within the "nipple". <S> Now I need to go to a LBS and ask if they could replace the thing. <S> Bottom line: don't use plastic screws: they are evil. <S> If you must, use a short-arm wrench e.g. 10 centimetres. <A> Burning plastic could make a big mess. <S> Use precision screws rather than plastic ones. <S> If you want to go fancy use precision screws made out of titanium parts. <S> They wont break. <A> I drill hole at center of plastic screw about 1/4inch and the broken screw Strat turning with some work it come out.
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The source of the problem was that the plastic body of the screw threads difficultly into the thread. Screw extractor : Inexpensive and easy to use. Next I tried a soldering iron. You will have to drill eventually.
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Significant difference between 28C and 32C tires? I have a Schwinn Sporterra 2011. It has a 622x20 rim and the default tires are 700x38C. I'm thinking of "upgrading" to thinner tires. Now, my local cycle shop has Specialized tires that are 32C. They can also get me Schwalbe 28C tires, but in 2-3 weeks time. What I'm trying to understand is, coming from 38C tires, how much of a difference will 28C or 32C make -- Difference to things like speed and handling? Will 28C be much "faster" and worth the long wait time? (I'm actually thinking of switching to a road bike in 6 months but till the time I save up for that, I want to get thinner tires on the current bike. I was told they'll make quite a difference. Thoughts?) <Q> They will make a significant difference, but the size of the tire alone won't make much of a difference to your speed. <S> If your current tires have a substantial amount of tread on them, you may notice a speed difference since smaller tires tend to have less tread on average. <S> It's probably not going to be a substantial difference though, even if you have the knobbiest 38's on the market. <S> Your biggest speed limitation is wind resistance, and while the narrower profile of the tires will knock that down a little, it's a small portion of the overall wind resistance that you experience. <S> Where you'll notice the biggest difference will be in how much harsher the ride will feel with skinnier tires. <S> They run at higher pressures <S> so you end up feeling every bump in the road more. <S> You'll also notice that the steering feels more nimble due to the lighter weight of the skinnier tires. <S> You'll also be more prone to pinch flats with skinnier tires. <S> To what extent will depend on the tire pressure that you've been running and the tire pressure you're going to run. <A> I have tested everything from 35 to 32, 28, 24 and finally to 23 from different brands. <S> The overall experience depends on several factors, most notably the kind of riding you do, your weight, frame design and material etc. <S> For the same tire type (ie a decent road tire) <S> I chose 28 (Continental 4 seasons) for my city/commute bike and I am quite happy but the ride is definitely harder, especially with my aluminium frame. <S> In conclusion, if you are heavy or ride bad roads, get the 32. <S> If you are skinny or ride good quality tarmac, you can consider 28. <S> Invest in good quality, things like tpi (threads per inch) are very important. <A> Another answer noted that tread pattern and tire pressure make a larger difference than the width. <S> If you have a smooth tread pattern at high pressure, you will roll more easily and the tire won't "squirm" going around corners. <S> Tire compound can also affect handling. <S> The worst tires I ever rode on were a cheap narrow-ish (maybe 28c) set with raised tread made of a harder rubber compound. <S> The traction was terrible: I could lock the rear tire even under fairly light breaking. <S> There is a connection between width and tire pressure. <S> Generally narrower tires support higher pressures, and also require higher pressures to support the same weight on a smaller volume of air. <S> Up to a point, running higher pressure will reduce rolling resistance. <S> If you run the pressure too high it may actually slow you down as small bumps will jostle you more. <S> The 32C tires will likely give a noticeable difference: the ride may be a little rougher but rolling resistance should be reduced, and you'll probably feel a little more certain on corners. <S> Contrary to the other poster, rolling resistance is less than air resistance, but is a significant factor at moderate speed: if you're riding at 25MPH, air resistance totally dominates, but at 15MPH, rolling resistance is non-negligible. <S> I would say just get the 32C tires and start riding on them: it's probably not worth the wait. <S> There's also a good chance that 28C might be too much of a good thing.
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You can try running wider tires at their max pressure to reduce rolling resistance and see how they feel, but it will likely give you a rough ride and have fairly poor contact with the road surface, compared with a narrower tire at the same pressure. Tires below 28 are only for road bike use, ideally with a carbon frame. a 32 tire will give good comfort for a heavy rider and is excellent for everyday use. Make sure you use the correct pressure .
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