Why Do My Motorcycle Brakes Squeak?

by Galfer USA

Nobody likes squeaky brakes. Whether it’s your bike or someone else’s, it’s like nails on a chalkboard and most of us just want it to stop. So what’s causing the squeak? We sat down with our brake material techs here at Galfer USA to find out what causes squeaky motorcycle brakes, what you can do about it, and when it might be time to take more serious action.

What causes squeaky motorcycle brakes?

First thing’s first. Check your pads to see how much material is left on them. If they get worn down too low, not only could they start to squeak, but they could be unsafe to ride on. Likewise, grab a set of calipers to measure the thickness of your rotors. Every rotor should have a minimum thickness stamped onto it, and when you get below that number you risk things like brake failure and rotor warping, so it’s time for some new rotors.

If your pads still have enough material on them, the squeaking is most likely caused by debris getting trapped between the brake pad surface and the rotor surface, or by contamination of either the pad or rotor. This can happen while riding, obviously, as dirt, oil or debris can get kicked up from the road or trail. But it can also occur if a foreign substance gets on your pads, rotors or both during installation or while working on your bike.

How do you fix squeaky motorcycle brakes?

Assuming the squeak is caused by contamination, the easiest way to fix this is to run some 500-600 grit sandpaper across the brake pad surface to remove anything that shouldn’t be there. It’s going to take a little bit of time, but make sure you get that surface layer off. If you notice any discoloration or glazing on the rotor surface, then you can also run 500-600 grit sandpaper along the rotor surface. Like the pads, do this until you see a nice, clean rotor surface again. In some cases, it can be helpful to wipe down the rotor surface with isopropyl alcohol or some brake cleaner, as this will help remove any deep-set grime or oils that the sandpaper missed.

(Pro Tip: wash your hands or use clean gloves when installing or handling your brake pads or rotors, as any oil, dirt or grime from your fingers can put you right back where you started.)

What if they’re still squeaking after cleaning?

In very rare cases, brakes will squeak not because of contamination, but because the vibration of the pads during braking reaches an audible frequency. This usually happens because of the shape of the pad or the pad compound in relation to the rotor surface. Manufacturers do their best to use brake pad shapes that work well with the size and shape of the rotors they’re being used on, but in some cases these issues may arise. Your best bet here is to change out the pad for a different shape or compound.

(Pro Tip: when inspecting or installing your rotors, check the mounting surfaces for any dirt or debris, as this can cause misalignment in the rotor.)

What if my brakes are STILL squeaking, even after cleaning and changing pads?

Then it’s time to take your bike to a shop or certified mechanic.

If you ever have any questions about your braking system, don’t hesitate to give us a call at (805) 988-2900 x 118 or email us at tech-support@galferusa.com.