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53

In terms of wearing out the brakes, they will wear less when you brake at the bottom. When you descend a hill you have a fixed amount of energy to lose, and when you descend at a higher speed, a larger proportion of that energy is lost to wind resistance. Practically however, brake pads/blocks tend to last a long time and are cheap to replace, wear is not ...


43

One should not trade their safety for prolonging brake pads life. Thus gaining the speed and hoping to lose it at the very end of the ride is not the wisest thing to do. Having said that the question is rather whether to: lightly but constantly brake maintaining more or less constant speed; or gain some speed, brake hard, repeat I'd opt for the latter ...


24

As a chain wears out, the distance between links gets bigger (this is what chain wear tools measure). As this is happening, the chain will grind the cogs to match the worn chain (distance between teeth increases). This is why your gears might not feel so bad, but then they get much worse when you put on a new chain. The new chain's links do not line up with ...


18

Your high CC-2 reading likely relates to how much pressure are applying. The CC-2 device is not particularly solid and its readings are sensitive to how much pressure you apply to the pivoting gauge. From the manual: Instructions Set pivoting gauge so “0” is visible in viewing window. Lower CC-2 so fixed pin rests between chain’s inner plates. ...


17

There are really two optimal solutions: Go as fast as you dare, perhaps slightly braking, maximize your frontal area (thereby maximizing air resistance) then brake at the end quickly. The idea here is that you are obtaining part of the braking force from air resistance due to the maximized frontal area and maximized speed. Go very, very slowly, braking all ...


14

I would say that this won't have any effect. Flipping the chainring on a single speed makes sense as you use the other side of the teeth on the chainring which have not been used before. But with the chain it's a different story: The stretch is independent of directions so reversing its direction won't change anything. Also on the small "rolls" in the chain ...


13

Rims last a lot longer than brake pads. It's difficult to put a number, as it depends on so many parameters, but personally I change brake pads roughly once a year (2-3'000km), and I haven't ever changed a rim due to it wearing out. (There has always been other reasons to change them.) On many rims there's a tiny groove in the middle of the braking surface. ...


10

Without experience, or obvious damage, a cassette gauge like the one from Rohloff, or mileage are your best options for deciding when to replace a cassette. For me, a good rule of thumb has been: 10 chains = 2 cassettes = 1 set chain rings That is, I change my chain every 1200-1500km. I change the cassette on the 5th time I change the chain. And I change ...


10

Interesting question. Real world conditions are messy with multiple factors impacting any analysis, as such my answer will be speculative, but based on a number of sensible working assumptions. Chainring degradation as a source First lets consider how much material comes off a chainring. Generally speaking, if you replace your chain regularly before it ...


9

While I'm not a road biker, I can speak from experience with mountain bike tires. The first spot to wear is the center of the tread. Why? It's the part that is ridden on the most. Increasing the width of your tire with increase the contact patch (the part of the tire touching the ground); therefore, your wear is going to be the same because that contact ...


9

It all very much depend on your conditions. If you have a lot of dirt and grime on the road, expect pads to wear out quicker. I'd say adjust pads position after 600km is normal, nothing to worry about.


9

0.8mm is very thin and dangerous. The mechanic is right to tell you to replace the rim! Keep it only if you want to play with your life because it may fail in a catastrophic manner! More dangerous even on a front wheel. Many rims have wear indicators, usually a couple of holes along the braking surfaces, that tell you that the rim is over the limit once one ...


9

A lot of chain checkers read the chain being worn to x% even on a new chain (esp. on higher speed chains). The variation in new chains and reading inaccuracies can make tools essentially useless. Following these tools will lead to you replacing your chain sooner than necessary. A better quality chain tool can help, or using calipers/a ruler as you are ...


8

The lifespan of brake pads is not only dependant upon environmental conditions but also very much upon what is put into them. I'm compelled to point out there is a massive difference between the compounds that manufacturers put into brake pads. I've no idea what compounds are actually in them but I'd describe some as "rubbery", some as "gritty", and many ...


8

This is common and is a result of the constant friction and increased heat of the small roller on the trainer. Larger diameter rollers will see lower degradation of the tire, but it will still be a problem. Most riders I know use less expensive tires, or older tires that they no longer trust for use on the road when they switch to the trainer.


8

More or less all contemporary multi-speed chainrings are like that. The idea is the different profiled teeth correspond to different areas of the ramps and/or pins to create specific assisted areas for shifts to occur.


8

The marginal cost of cycling is extremely low (i.e. the cost for an extra bit of use), especially as kids' lessons are going to be light use (I doubt they're hurtling off kerbs, for example). Kids' bikes are also heavily built in proportion to their riders, who are weak compared to adult riders, while the chain (for example) is unchanged. Depreciation of ...


8

This is a common misconception. The shorter teeth are not chipped or broken off. Modern chainrings and cassette sprockets have features to assist the derailleur with moving the chain. The shorter teeth allow the chain to more easily move off the chainring and onto an adjacent one. Definitely fairly well worn. Personally I'd stay away from something this ...


8

I've done the opposite to a lot of riders - I had a chainset of unknown mileage and rather than guess, I simply rode the whole thing into the ground. Shifting got progressively worse over time, but it wasn't linear. There were certain gear combinations that slipped more under normal load, and others that slipped under heavy load. Climbing a grade became ...


7

Trainers are notorious for chewing up regular tires. They do sell trainer tires that are built to take the rubbing and wear that a trainer dishes out. What a lot of people do is buy a cheap wheel (Such as a neuvation or similar), throw a trainer tire on it and use that when they mount their bike to the trainer.


7

I don't know exact numbers, but you will know when you need to replace your wheel when the rim starts to have a concave feel to it when you run your fingers over it (I'm talking about aluminum rims here). An extremely bad case will look something like this: Don't let your rim ever get here, but this is a good example of what your rim will do if you let it ...


7

From the info you've given it's hard to tell how old your bike/the spokes are. If the spoke tension is too low/if there is too big a difference in the tension of the spokes in the wheel this can cause premature spoke failure due to uneven force distribution over the spokes in the wheel. Make sure to have proper spoke tension/tension distribution to prevent ...


6

As @GaryRay has stated trainers are tough on tires. One condition that accelerates the wear is low pressure in the tire and high pressure on the roller. Many riders would not think of going for a ride without checking tire pressure but forget about checking the trainer tire. The low pressure on the tire and high roller pressure generates heat from the ...


6

I suspect that the abrasion from road/chainring/cogs is negligible, especially when comparing with other causes. The silica grains (SiO2, present almost everywhere) would be more of a worrying issue than the aluminium oxide, regarding chain wear. The grains are often visible (in sub millimetre size) and easily stick on the chain after a ride on any road ...


6

25000 km isn't a lot. There isn't a time or mileage you should consider swapping out a frame. Instead, you should look for damage, such as dented tubes or cracks. You should be especially wary if you've been in an accident to check your bike out. Carbon fiber complicates this a bit, because its failure modes are generally more rapid than metal and harder ...


6

The load is spread across more teeth on the chainrings than on the cassette, so they tend to last quite a bit longer. If they said your chainrings are fine, then they are probably no problem. derailleurs don't really have many parts that can wear out. There isn't much load being placed on the jockey wheels, so they can last quite a long time. The spring ...


6

There is no way you can accurately assign a distance to disk brake replacement. Someone commuting in a stop and go method in a wet climate like the pacific northwest will get much less life out of their setups than someone living in a drier/cleaner climate and a more continuous commute. Anyone can determine the relative life left in their setup by looking ...


6

When the chain is bent sideways, the load at links is concentrated on one end of the pin and single side plate while the link is turned. This is supposed to wear that side of the link faster. Once the link is worn asymmetric, even straight chainline will concentrate load on the less worn side. No, I don't know if there are any actual measurements on this.


6

This question is about whether you should execute the bicycle equivalent of a suicide burn. It is faster and more energy-efficient to brake as hard as you can as late as possible than to control your speed early. For a rocket this means sparing fuel, for your brakes this means producing less heat. Do note that the name doesn't come from nowhere. It's too ...


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