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How bicycle coaster brakes work (2018)

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Re: How bicycle coaster brakes work (2018)

#71

Post by lstodd »

david-gpu wrote: post #64
lstodd wrote: post #60

Earlier quoted context omitted.

That's a lowside. Turn very gently if weather invites ice (or wet autumn leaves which are about as creepy as ice), never use front brakes. Locking and then suddenly reacquiring grip on the rear wheel causes highsides on motorbikes, it's when you fly out of the seat and into the oncoming 18-wheeler. But it's quite hard to do on bicycles. Fronts are useful when you have to decelerate rapidly while travelling in straigh…

Braking while turning is a risky business indeed. You typically want to use both brakes at once to reduce the chance of skidding, but if you do lose grip on either wheel nonetheless, you better have quick reflexes and release both brakes. Sheldon Brown talked about this [0]: > Skilled cyclists use the front brake alone probably 95% of the time, but there are instances when the rear brake is preferred: slippery surfac…

What he names "fishtailing" is what is known as "highside" in motorbike circles. When the rear wheel loses grip, it and the entire frame except the front fork moves sideways. When the rear wheel inevitably retains grip, the resulting force violently flips the whole. On a bicycle this is rare and survivable, on a 200+kg mc not very much so.

In a turn you either apply energy if that is at all possible (usually), or just steer. It is recommended to accelerate inside a turn, because that way you can better control grip on the rear due to not accidentally engine-braking (not applicable to bicycles), and because thrust on the rear wheel helps the bike into the turn (applicable to bicycles).

Braking in a turn is a last-effort thing, taken only if you are certain that it'll lessen damage from otherwise imminent crash.

Biking is traction/grip control at all times. Traction is always shared between steering and brake/accel. You do not want less control in a turn, and loss of traction means loss of steering.

So you do not ever brake in a turn.

You decelerate on a straight before it. If a turn goes bad for whatever reason, that means that a) you made a mistake entering it at the speed you did, and b) now you choose what to crash into, and then execute the crash while hoping that your protection holds, which might include hard front brake and a steering input so that you lowside feet (and bike) first into the obstacle. But not before.

So the first lesson of bike-riding is being aware at all times of available traction.

95% use of fronts follows: you only use them on straights, and there they are much more efficient than rears because the whole mass of you and bike enhances front wheel traction. cf. the wheelie.

Re: How bicycle coaster brakes work (2018)

#72

Post by kakacik »

lstodd wrote: post #60
fransje26 wrote: post #51

Earlier quoted context omitted.

> Once you overlook a section of black ice, not even the nicest hydraulic disc brakes will be gentle enough. My experience with black ice and bikes, is to unexpectedly fall flat on my face because the front wheel loses all grip. Without even getting to the point of trying to brake..

That's a lowside. Turn very gently if weather invites ice (or wet autumn leaves which are about as creepy as ice), never use front brakes. Locking and then suddenly reacquiring grip on the rear wheel causes highsides on motorbikes, it's when you fly out of the seat and into the oncoming 18-wheeler. But it's quite hard to do on bicycles. Fronts are useful when you have to decelerate rapidly while travelling in straigh…

> edit: and on a decent motorbike/scooter you learn to not use brakes except in emergency, 95% of all deceleration is handled by just dropping the throttle.

There are 2 benefits of actually using brakes (smartly as comments say) - leaving deceleration to the motor wears it down much faster, and repairs are more complex/expensive than changing pads/disc of brakes. Second reason is more important - folks behind you know whats happening, thats why brake lights are so strong. Don't expect 100% of the folks watching you closely 100% of the time, thats incorrect and dangerous expectation. On bike you are the most fragile participant of the traffic, its in your interest to signal your behavior to others as clearly as possible.

Re: How bicycle coaster brakes work (2018)

#73

Post by analog31 »

japanuspus wrote: post #49
Hobadee wrote: post #15

Where is all this love for coaster brakes coming from?! They are, IMHO, one of the worst brakes ever. They have caused me numerous spills and scraped knees (due to the rear wheel locking up and skidding out from under me) and have done the same to my kids. There is virtually no control over them, and they don't allow you to shift your weight around when standing on the pedals to go around sharp corners or off-road. (…

As the family bike maintainer in Scandinavia, hub gears and coaster brakes are a godsend: Simple, cheap, and the only wear item to replace after a winter driving in salty sludge is a cheap chain -- and this takes half the time if there are no brake cables to detach. This might be a Nordic thing, but being able to handle rear wheel lockups is a necessary skill when driving on winter roads. Once you overlook a section…

It's also a thing in the upper Midwest of the US. One trick is a studded winter tire in the front and a regular tire in back. The front tire keeps you in control without too much of a rolling resistance penalty. We have enough space here that we can afford to have dedicated bikes for winter riding. In the spring, I hose them down, spray on some light oil, and stow them away under a makeshift awning in the backyard.

Re: How bicycle coaster brakes work (2018)

#74

Post by david-gpu »

lstodd wrote: post #71
david-gpu wrote: post #64

Earlier quoted context omitted.

Braking while turning is a risky business indeed. You typically want to use both brakes at once to reduce the chance of skidding, but if you do lose grip on either wheel nonetheless, you better have quick reflexes and release both brakes. Sheldon Brown talked about this [0]: > Skilled cyclists use the front brake alone probably 95% of the time, but there are instances when the rear brake is preferred: slippery surfac…

What he names "fishtailing" is what is known as "highside" in motorbike circles. When the rear wheel loses grip, it and the entire frame except the front fork moves sideways. When the rear wheel inevitably retains grip, the resulting force violently flips the whole. On a bicycle this is rare and survivable, on a 200+kg mc not very much so. In a turn you either apply energy if that is at all possible (usually), or jus…

I would separate cycling from riding motorbikes entirely. They are different enough in terms of mass, speed, and especially acceleration.

As an example, pedaling while turning is often a bad idea because of the risk of pedal strikes, so acceleration inside a curve is often out of the question. And braking obviously reduces the grip available for turning, so braking while turning is only done in an emergency situation. But if you are going to brake while turning, using only the rear brake is suboptimal on a bicycle.

Re: How bicycle coaster brakes work (2018)

#75

Post by IslandRebel »

Gualdrapo wrote: post #18
Hobadee wrote: post #15

Where is all this love for coaster brakes coming from?! They are, IMHO, one of the worst brakes ever. They have caused me numerous spills and scraped knees (due to the rear wheel locking up and skidding out from under me) and have done the same to my kids. There is virtually no control over them, and they don't allow you to shift your weight around when standing on the pedals to go around sharp corners or off-road. (…

In my experience hydraulic disc brakes require less maintenance than rim brakes. Living on a hill (like I had to go up a ~150m 23% wall to get home, and go braking down it to go places) meant I had to spend frequently on rim brake shoes and, eventually, rims. The frequent rain and mud makes it to the rim brake shoes and diminish braking power if you don't keep them clean. That doesn't happen with hydraulics - clean t…

Rim brakes last ages. I used to ride 100 miles a week easily up and down hill on my mountain bike V-brakes for 3 or 4 years and had to change the pads like maybe twice.

Maintenance of cantilever and v-brakes is changing the pads every so often and putting some oil/grease on the cable/replacing the cables. None of this is that difficult.

I don't understand why people pretend that lining up some pads, and then adjusting the cable is super difficult

> The frequent rain and mud makes it to the rim brake shoes and diminish braking power if you don't keep them clean.

People greatly exaggerate how much of an issue this is. I could lock up the wheels even in the wet and muck with V-brakes. TBH, You have to ride to the conditions anyway.

Re: How bicycle coaster brakes work (2018)

#76

Post by kqr »

usrnm wrote: post #68
kqr wrote: post #62

Earlier quoted context omitted.

> But when we switched to hand brakes, it became impossible, as you need a free hand and speed control at the same Did y'all have only one hand?

Breaking with just the front wheel break is a very bad idea, so you always need the rear wheel hand to break

What makes the front wheel brake a bad idea? I almost exclusively use the front brake, because that's the one that'll actually stop me. (Source: when I used rim brakes I had to replace the front brake pad three times for every time I replaced the rear brake pad.)

I know some people use the rear wheel locking up as a way to sense when they have applied enough front brake, but that's not necessary. It's also possible to learn to sense that directly.

Re: How bicycle coaster brakes work (2018)

#77

Post by usrnm »

kqr wrote: post #76
usrnm wrote: post #68

Earlier quoted context omitted.

Breaking with just the front wheel break is a very bad idea, so you always need the rear wheel hand to break

What makes the front wheel brake a bad idea? I almost exclusively use the front brake, because that's the one that'll actually stop me. (Source: when I used rim brakes I had to replace the front brake pad three times for every time I replaced the rear brake pad.) I know some people use the rear wheel locking up as a way to sense when they have applied enough front brake, but that's not necessary. It's also possible t…

When going at a high speed, breaking hard with the front wheel alone can force the bike to rotate around it and the rider might enjoy a very short but very thrilling flight. Which I learned the hard way many years ago

Re: How bicycle coaster brakes work (2018)

#78

Post by wolrah »

kakacik wrote: post #72
lstodd wrote: post #60

Earlier quoted context omitted.

That's a lowside. Turn very gently if weather invites ice (or wet autumn leaves which are about as creepy as ice), never use front brakes. Locking and then suddenly reacquiring grip on the rear wheel causes highsides on motorbikes, it's when you fly out of the seat and into the oncoming 18-wheeler. But it's quite hard to do on bicycles. Fronts are useful when you have to decelerate rapidly while travelling in straigh…

> edit: and on a decent motorbike/scooter you learn to not use brakes except in emergency, 95% of all deceleration is handled by just dropping the throttle. There are 2 benefits of actually using brakes (smartly as comments say) - leaving deceleration to the motor wears it down much faster, and repairs are more complex/expensive than changing pads/disc of brakes. Second reason is more important - folks behind you kno…

> leaving deceleration to the motor wears it down much faster

Not in the slightest, and I have no idea where this idea even came from. Whatever amount of stress the engine and rest of the drivetrain is under even at maximum engine braking, it experiences significantly more under any hard acceleration. Even semi truck jake brakes that actually reconfigure the engine's air flow to generate even more deceleration forces than would otherwise be possible max out at a fraction of the acceleration powers that same engine is capable of producing.

The only part of a standard automotive drivetrain that has significant directional differences in strength/wear would be the differential gears, but even that difference isn't going to matter in anything close to normal use. If you're doing clutch drops in reverse that's another matter.

The biggest risk to anything drivetrain-related from engine braking would be badly shifting a manual transmission and either damaging the transmission itself or choosing the wrong gear and over-revving the engine.

The brake light thing I fully agree with you though. I love engine braking when I'm doing performance driving as much as the next guy, but I won't do it in traffic for anything more than holding speed on a downhill for that reason. Significant deceleration in traffic should always be accompanied by brake lights.

Re: How bicycle coaster brakes work (2018)

#79

Post by theodorethomas »

thesuitonym wrote: post #9
bariumbitmap wrote: post #2

> The disadvantages of coaster brakes are that the pedals cannot be adjusted while standing over the bicycle frame. Another disadvantage not mentioned in the post is that with coaster brakes the pedals can get trapped by the kickstand. I don't remember the details because this was a long time ago, but I accidentally found myself in a situation where I couldn't pedal forward because the kickstand was in the way, and c…

You can get out of this situation by rolling the bike backwards. Since the clutch is engaged it will also move the pedals in the reverse direction. Thanks for unlocking that memory for me, it's been decades since I had to know that.

Yes, this is how I used the "handbrake" function to "park" on a steep uphill.

Re: How bicycle coaster brakes work (2018)

#80

Post by ninininino »

Hobadee wrote: post #15

Where is all this love for coaster brakes coming from?! They are, IMHO, one of the worst brakes ever. They have caused me numerous spills and scraped knees (due to the rear wheel locking up and skidding out from under me) and have done the same to my kids. There is virtually no control over them, and they don't allow you to shift your weight around when standing on the pedals to go around sharp corners or off-road. (…

I believe there's a strong, slowly growing cultural backlash to interrelated concepts of planned obsolescence, design that assumes maintenance burden doesn't matter, durability and simplicity, and hatred for depreciation.

Coaster brakes are an example of a simpler design, that requires less maintenance, that are cheaper, that are poor in some environments like hills but are fine in flat areas.

Some would rather walk their bike down a hill but have a bike that never needs brake maintenance than to have better brakes that are a point of failure.

The same drive that pushes people to trying to build offgrid homes is slowly growing in spaces of material goods and home goods and such. Add environmentalism to it also.

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