Why do the brakes lock?

Question

Why do the brakes lock on a bike?

A friend of a friend of mine had a bad injury on his bike. The brakes locked and he was only going about 20mph. He was shot off the bike.

Why do the brakes lock?

How is it preventable?

How do anti-lock brakes work?

Answer 1

first don't know of any bike that have anti lock brakes

next there are two reasons the brakes may have locked

One the owner/operator did not make sure the bike was in top shape for riding like making sure the brakes where in good shape.

two rider error the rider did not have the skill to ride the bike or just got a case of the dummies and lock the brakes by stepping on and pulling the brakes to hard

Answer 2

Brakes lock because the rider doesn't know how to ride.  More than likely it was the rear brake, right?  In a panic, inexperienced riders do exactly what comes naturally, i.e. slam their right foot onto the brake pedal like they were in a car.

This locks up the rear tire, sends the bike sideways just far enough for the tire to catch again and slingshot the rider off into what is called a highside crash.

This is why training and practice are so important. A motorcycle is NOT a car and will hurt you if you try to operate it like one.

Answer 3

Anti-lock brakes are controlled by a computer that doesn't allow them to clamp down on the rotor some much as make a lot of quick grabs.  I believe that some BMW and Gold Wing motorcycles have them.

Sometimes new riders panic and brake hard in a slow turn and launch over the 'high side' of the motorcycle.

The rear brake linkage (drum brake) can  get dirty and lock.

Answer 4

brake caliber or something broke most like and really you never know when  it might happen .. just like a car you can never guess to when something happen.. only by keeping care of it and checking everything every ride.. and then not able to see all break downs...anti-lock brakes brake and releases to pervent brake from locking the wheel up.. and it wouldnt help help much in a brake fail

Answer 5

the brakes lock if you put them on too hard. He needs to do some rider training to learn how to apply his brakes properly. If your brakes lock, you must let them go so the wheels will start turning again to regain control. Anti lock brakes go a long way to avoiding this problem. The trouble is, not many bikes have anti locking brakes.

Answer 6

One big thing to add to the end of Noel W's response.  If you have locked up the back brake, you do NOT want to immediately release the brake if you're going at a fairly decent speed, because when you lock the rear wheel, your back wheel will start skidding and fishtailing.  However, when you release the lock on the back brake, the wheel will start turning and SNAP back into line with the front wheel.  However, this snap back into place can high side you off of the bike, so be careful if/when you lock up the rear brake.

Answer 7

I think that it is one of those things. Brakes are like everything and they can break (but thankfully it is rare).

I don't know if it is preventable. A few months ago a famous road racer called Robert Dunlop was killed when his bike just stopped when he was going at 160 mph during the North west 200 in Northern Ireland.

I don't know if it was the brakes that locked, but his bike just stopped dead. He was a professional racer so his bike would have been looked after by engineers so it would have been the last bike you would expect to suffer from engine failure.

Anti-lock brakes basically work by continually squeezing the brake disc instead of just gripping it. This allows the wheel to carry on turning so you still have control.

However, if anti-lock brakes fail, then I think there is the same chance of having an accident as conventional brakes.