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Comment by japanuspus | Hacker News Reader

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 of black ice, not even the nicest hydraulic disc brakes will be gentle enough.

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> 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 straight line, but in turns you just don't touch them ever.

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.

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 surfaces, bumpy surfaces, front flat, broken [front brake]

> When leaning in a turn, traction is shared between braking and turning. Using both brakes together reduces the likelihood that one wheel or the other will skid and dump you. The steeper you lean, the less you can brake, so moderate your speed before a curve. When you are leaning deeply, you need to release the brakes entirely.

> Using both brakes together can cause "fishtailing." If the rear wheel skids while braking force is also being applied to the front, the rear of the bike will tend to swing past the front, since the front is applying a greater decelerating force than the rear. Once the rear tire starts to skid, it can move sideways as easily as forward.

I broke some ribs a couple of years ago on a downhill trail due to fishtailing. I should have dismounted, but I had not realized that the surface had turned from gritty to muddy.

[0] https://sheldonbrown.com/brakturn.html

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.

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.

And you don't normally need to consciously countersteer on a push bike because of some combination of 1) lower speed and 2) much higher body mass relative to the bike, but countersteering is absolutely essential on a motorbike

Countersteering is important on a bicycle too when you need to quickly dodge something, for example. But yeah, the stakes around riding are so much higher on a motorbike.

On a bicycle if you can modulate the brakes so it never loses grip and you adjust your balance you can use both brakes in corners - I’ve been doing it most of my life, sometimes at speed and have done it on extremely steep slopes to avoid trees and obstacles. It’s possible without the rear wheel being on the ground at all, just never lock up or lose traction on the front wheel but that takes (sometimes painful) practise.

It doesn’t feel as good as decelerating before, and is most definitely not as safe as you clearly explained.

Well, IF. If you have enough skill you can a do stoppie in a turn, turn around and shoot off the way you came from. But this is bordering on stunt riding, not something to be relied on for day-to-day riding where you have to have enough margin to account for being not very focused, road having various low-friction crap that fell off a truck, crazy pedestrians, car drivers asleep etc.

> 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.

> 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.

I just adjust the brake handle light switch so that lights go up before there is any brake force applied, so that you can float it just by feel. Idk, this is what 90s japanese bikes did right from the factory. Then train that "drop throttle" is equivalent to "pull front brake to ready" and light comes on.

It's motorcycling basics really.

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.

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