How to stop squeaky disc brakes

A squealing or vibrating disc brake is one of the most common problems we see in our Barcelona workshop. In most cases the cause is contamination of the pads or rotor (oil, chain lube, cleaning products or even fingerprints), glazed pads after long descents, or a caliper that is not perfectly aligned with the rotor.

Step by step

1. Check the alignment: spin the wheel and look through the caliper. If the rotor rubs on one side, loosen the two caliper bolts, pull the brake lever and retighten them while holding it.
2. Clean the rotor with isopropyl alcohol or a specific disc brake cleaner and a clean cloth. Never use degreasers that leave residue.
3. Remove and inspect the pads. If they are shiny (glazed), lightly sand them on fine sandpaper. If they are soaked in oil, replace them: contaminated pads cannot be recovered.
4. Bed in the pads again: 10 to 20 progressive stops from moderate speed, without locking the wheel, so the pad material transfers evenly to the rotor.

Tip: when you lube your chain or wash the bike, cover the rotors. Most noisy brakes start there.