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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 ...


38

The answer heavily depends on the groupset construction/generation and personal perception of what is "bad", among other factors. Below are a few aspects that I am aware of. Switching gears in the traditional bicycle drivetrain assumes there is a momentarily side load on the chain, twisting it and forcing it to jump/fall from one cog to another. ...


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 ...


19

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 ...


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. ...


13

Yes - after that mileage you will need both a new chain and new cassette. A new chain on the old cassette will not mesh right, and accelerate wear on the new chain. Depending how much chain elongation has accrued, you may need new chainrings too. They wear slower because more teeth are engaged in the chain. Look at the chainring and see if the scallops are ...


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 ...


10

You can quite easily get your chain dropped. If you were standing and pushing hard in a climb you could even fall. If the chain drops to a bad place, it can damage your frame near your bottom bracket or it can damage your spokes or similar.


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

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 ...


9

I don’t think it’s a bad idea, but be prepared to repair stuff. Things even a novice should be able to check: Frame and fork without damage (i.e. no cracks or dents, nothing bent). Small paint chips or scratches are okay. Shifting to all gears works. Braking works. Wheels are true, no damage to the rim or spokes. This ensures that the most expensive ...


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 ...


8

The other posters are probably right. But, if you haven't money to burn, I would replace the chain first and see how it goes. You say you keep it clean and well lubed so damage to the front chainrings are less likely and unless you seldom change gear, the cassette may be good enough to last another chain. Have a look at the teeth to see if they look like ...


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 ...


7

The rim brakes on my last bike had a barrel adjuster that did what you ask. My new bike has disk brakes and they self-adjust. The barrel adjuster here is the black cylinder on the right-side. The brake housing/cable pass through the middle. To bring the pads closer to the rim, rotate the barrel adjuster so it comes out from the lever's body by a turn or ...


7

Expanding on a comment I made on Gregory's answer: I agree fully that it's better not to shift under load. However, modern drivetrains are much less sensitive to shifts under load than older ones. You will have noisier rear shifts. For front downshifts, I believe there's a small chance you can drop your front chainring; as Vladimir stated, on some frames you ...


7

I think that one rule of thumb I saw asserted that if you replaced promptly, you could get 2-3 cassettes per chain, and 2-3 sets of chainrings per cassette. I'm not able to provide a concrete source for this right now. However, the fact is that chainrings do wear more slowly than cassettes because they have more teeth. I think very likely that your cassette ...


7

The SunRace crankset is cheap. They are still available and probably have an identical specification. The cheapest types have non removable chainrings. The steel used to make them is not particularly hard wearing and they will wear fast with a worn chain. My experience is that you can get slipping from the chainring, though these usually wear more slowly ...


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

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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