Drum Brake

A drum brake has a hollow drum that forms part of the wheel hub. Inside, two curved brake shoes with friction lining sit on a fixed backplate. When you brake, a cam, operated by a cable or rod (or on some vehicles a hydraulic wheel cylinder), spreads the shoes outwards against the inner surface of the drum.

Drum brakes are cheap, compact and well sealed against dirt, so they are still used on small motorcycles, many scooters, classics and some ATVs. They are less powerful than disc brakes, dissipate heat poorly and fade more easily under hard use.

Adjust free play as the shoes wear; many have a wear indicator on the cam arm. Water in the drum reduces braking until it dries, so brake lightly after a water crossing. Clean out lining dust with a brake cleaner, not compressed air.