FROM THE WORKSHOP...
They are becoming the bane of my cycling life, so how do I cure squeaky disc brakes?
If your disc brakes make a rubbing noise, or worse, squeal, there are a few things you can do to remedy this, or prevent it happening in the future.
Often unwanted contact is caused by poor positioning of the calliper in relation to the disc. To alter this, simply grab a 5mm Allen key (or T25 torx in the case of SRAM) and loosen the calliper bolts until the calliper can move a little on its mounts. Then rotate the wheel towards the calliper and pull on the lever to activate the brake. Hold and re-tighten the bolts and this should square it up nicely. This is often the right solution for a small amount of rubbing or contact, and also should stop a squeaking disc. If the squeaking continues, however, you might have contamination on the disc or pads, which means they might need replacing. You can prevent contamination by never spraying aerosols or lubricant fluids near brakes. If you do have overspray from lube and cleaning agents contaminating the pads, and want to have a go at cleaning them, wash them with a mild soap and water solution to remove oily residues, rinse with fresh water and then wipe clean. It can also be worthwhile deglazing the surface of the rotor disc by roughing it up with fine sandpaper or an emery cloth.
STOP CONTAMINATION BY NEVER SPRAYING AEROSOLS OR LUBRICANT FLUIDS NEAR BRAKES