Brake Cam: The mechanism that releases the Brake Pads in a Drum Brake.

Drum brakes are mechanically actuated—that is, via a Brake Lever or Brake Pedal, Brake Cable, Lever, Shaft, and Brake Cam. The Brake Cam is located between the Brake Pads and spreads them apart when braking, so that they press against the drum and apply the brakes.

• Replacement for worn components
• Optimal braking performance
• Optimal control of braking force

In this process, the metal of the cam rubs against the metal of the Brake Pads and wears down over time. Lubricating it with Copper Paste or high-temperature grease helps counteract this wear. But even if the brake has always been meticulously maintained, wear is still to be expected after many years of use.

A worn edge on the cam’s sliding surface not only reduces braking effectiveness but also affects the brake’s modulation. Ideally, braking performance can be precisely controlled via the Brake Lever or Brake Pedal. If, for example, the rear brake locks up, it should be possible to release it in a controlled manner by reducing the pressure on the Brake Pedal.

However, if the cam is worn, it may happen that while the pressure on the Brake Pedal is reduced, the brake itself sticks and the Brake Pads are not returned evenly by the Spring. Especially when it comes to brakes, it should be clear that all components must be in top condition, no ifs, ands, or buts. That’s why SIP strongly recommends regularly checking all brake components for wear and replacing them as needed.