Disc brakes are amazing when it comes to riding a mountain bike. Their stopping power, no matter the weather, is unbelievable and decreasing your speed downhill has become a whole lot easier. Now that disc brakes are offered on a variety of bikes, most riders are bound to hear that annoying squeaking sound at some point.
There could be a ton of reasons why your disc brakes are making that awful sound, but here are a few reasons why and a few tips to help fix it.
If you hear squeaking, squealing or pinging noises that occur while you are riding at consistent intervals, it might mean there is a caliper alignment issue or a bent rotor that is causing your brake pads to rub. You can check this by lifting your wheel off the ground and giving it a spin. If the wheel does not spin freely and comes to a stop, you have a brake rub issue!
How to Fix:
Check to make sure your wheel is properly seeded in the dropouts of the fork or chainstay. This might be a problem if you are running a wheel with quick release skewer that doesn’t thread into the frame.
Then check the alignment of the caliper. Loosen the caliper bolts and wiggle the caliper loose, then hold down the brake lever. By holding down the brake lever it should center the caliper over the rotor with the help of the brake pads. With the brake lever pulled, tighten the caliper bolts equally and evenly. Then try spinning the wheel again to check for rubbing.
Contamination of Your Break Pads:
If the noise is really loud and consistent when braking, then most likely your brakes are contaminated. Brake pads are like a sponge and will soak up everything, including; lube, polish, degreaser, and brake fluid.
How to Fix:
If you believe you have gotten any oil or grease on your brake rotors, clean them off with a clean rag and isopropyl alcohol. If you have already contaminated the pads, then try removing the pads from the caliper and carefully sanding down the outer layer with fine-grained sandpaper. However, if your brake pad and chain lube became best friends, it’s best you replace the brake pads.
Water and Heat:
It’s definitely possible that water and heat can cause your brakes to make a little too much noise. Sometimes just riding through a puddle can cause your brakes to squeak. The easy solution is as you use your brakes, the squealing noise will reduce.
When you constantly brake for longer periods of time (downhill riding for example), the heat produced by that can cause your brakes to howl and it possible that won’t go away.
How to Fix:
If your brakes become overheated, the rotor will become discolored and will then need to be replaced. If you consistently have this problem, it usually means you need a bigger brake rotor. Larger rotors help increase the braking power, and lessen the heat, which then means less noise.