How bicycle coaster brakes work (2018)

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. (Nevermind trying to shift your weight backwards when stopping quickly)

I have hydraulic disc brakes on my bike, and they are the greatest thing ever! Yeah, they require maintenance, but totally worth it.

Brilliant for folks in flat cities riding to and from work. That's the environment in which they got popular 100y ago. For hills def need rim brakes or discs for flexibility of use. BMX racing in early 80s we used the lightest rim brakes and levers we could find. I had couple of times snapping the levers and even the brake arms before fitting with really strong machined aluminium ones which lasted me 3 years before I stopped riding.

> The coaster brake also can be prone to locking up the wheels and causing the tire to skid. For kids this is an advantage, since they enjoy putting bikes into a sideways skid.

Damn well it was! I remember we used to play tag on bikes. But when we switched to hand brakes, it became impossible, as you need a free hand and speed control at the same time.

> 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 couldn't pedal backward because the brakes engaged. I don't remember how I fixed it.

Biggest advantage is that they keep your hands free while braking.

"The coaster brake also can be prone to locking up the wheels and causing the tire to skid. For kids this is an advantage, since they enjoy putting bikes into a sideways skid. This seemingly is a one of the requisite skills for youthful riders, especially but not exclusively boys."

Very accurate.

Retired cycle tourist here: Australia, China, Laos, France, Romania, Taiwan, Thailand.

This is interesting, I recall having some of these as a kid.

I'd say the key drawback not mentioned is that, in many riding conditions (such as but not limited to riding when in close proximity to vehicles, riding in high wind, riding in proximity to severe drops or road discontinuities, riding with heavy loads, riding downhill with luggage encountering sharp bends, repositioning legs for a hard ascent, etc.) you cannot always freely alter your physical stance to apply additional pressure to the braking system (as it may upset other concerns) nor can you afford a short latency to reposition to your stronger leg before applying the brake (or a short burst of climbing on difficult terrain).

So while functional in most conditions, I'd say they are in fact objectively inferior in terms of latency and control and thus safety and utility in many realistic conditions.

What could be an improvement (and may have been made already) is a speed-gated clutch, that is to say, slow reverse is permissible but a burst above the gate speed enables braking. This could solve a minority of the issues in terms of control at the cost of complexity.

Wow, I was just the other day wondering how these work. Far more complicated than I had expected, but a very cool mechanism!

I love coaster brakes! its one of the few parts of a bicycle I cannot fix (that, and wheels/spokes/truing)

These brakes are far more complicated then I was expecting. But do last forever.