Disc brakes have become widely used in the cycling industry, and many types of bikes are being designed to utilize their advantages over rim brakes. Most recently, there has been a push for disc-equipped road and cyclocross bikes. With all these different uses come different models, compatibility concerns and a huge selection of features. We’re going to try and simplify things here.
How Do Disc Brakes Work
Typical front disc brake setup Before digging too far into the broad spectrum of bike disc brakes, we’ll quickly discuss how they work. The most basic explanation is this: two pads squeeze a brake rotor -- shaped like a disc -- which turns mechanical energy (forward motion) into thermal energy (heat). In rim brake systems, the wheel acts like the brake rotor. Disc brake rotors are much smaller than wheels, which means more force must be applied from the brake pad to the rotor in order to create a sufficient amount of stopping power. This allows for better control of the braking forces because you have a broader range of force that can be applied to the disc rotor, creating a smoother transition from no braking to some braking too hard braking to locking up the wheels.