Posted on 5/25/2021
Disc brakes are called disc brakes because of the big metal disc – or rotor – that spins with the wheel. The brake pads rub against the rotor to slow the vehicle. In technical terms, the motion energy of the moving vehicle is transferred into heat energy by the brakes. The job of the rotor is to absorb that heat and dissipate it into the atmosphere. To do that effectively, the rotor needs a certain amount of mass (measured by the thickness of the rotor) and a good surface to mate with the brake pads. Let’s talk about those two things. First is the thickness. A new rotor is nice and thick. It can absorb a lot of heat and dissipate it effectively. Over time, the rotor will wear away slightly. If it wears away too much, there is not enough metal to take care of this heat transfer and the vehicle will not brake as well. In fact, each rotor is stamped with the minimum thickness the rotor must have. When the ... read more