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How Brake Shims Work

Motorcycle Brake Shims
Motorcycle brake shims help with alignment and reduce noise.
Motorcycle brake shims help with alignment and reduce noise.
White Cross Productions/Photographer's Choice/Getty Images

In addition to shielding heat and reducing noise, motorcycle brake shims are an important alignment aid. If a wheel isn't perfectly centered, a motorcycle brake shim inserted between the brake and rotor can bring it to true.

Since motorcycles don't usually generate the kind of heat that racecars do, the types of motorcycle brake shims you'll find are usually of the stick-on rubber variety, rather than titanium. These rubber brake shims reduce noise and vibration, making for a more comfortable ride. They also protect the brake pistons from overheating, which improves safety.

The shims also function to snug the friction surface of the brake pads against the rotors. The more of the friction surface that comes into contact with the rotors, the more stopping power the brake parts will be able to generate.

Though the humble brake shim serves a simple purpose and sometimes is an underestimated brake part, its assistance in wheel alignment and bettering maximum braking power is important. It helps reduce uneven wear and tear on brakes and increases the safety, giving both bike and rider a smoother and more comfortable ride.

­If you have a need for speed and want to know more about the brake shim or another brake part, shimmy on over to the next page.