You’re out on the road or trails, kitted out like a pro. You look the business, but then you pull on your brakes, and there’s an ear-piercing screech. Suddenly, all eyes are on you – embarrassing or what?
Why are your brakes squeaking?
Before we jump into the detail, it’s worth pointing out that your brakes will never be completely silent. But the only sound you should hear is a gentle whoosh. Any other noise means you need to do some maintenance.
If you have a squeaky chain, the first thing you do is reach for the oil or grease. Do not do that for your brakes. Although it will probably stop them from squeaking, it will also prevent them from stopping you – ouch!
Squeaky bike brakes happen for several reasons, including grease or oil on the brake pad, rotor or wheel rim (contamination) and misalignment. How you deal with the squeak will depend on what’s causing it and whether you have rim or disc brakes.
What type of brakes do you have?
The two most common types of braking systems are rim and disc.
Rim brakes stop your bike by pressing two brake pads against the rim of your bike’s wheels with the braking mechanism mounted on your bike's frame near the upper part of the wheels.
In contrast, disc brakes sit in the centre of each wheel and stop your bike when brake pads are pressed against a rotor mounted around the hub.
How to stop squeaky rim brakes
Before we go through the potential causes of your annoying squeak, the first thing to do is to check that your brake calipers and brake blocks are clean and in good working condition. It’s also worth checking that all bolts securing the caliper to the frame and the brake blocks to the calipers are securely tightened.
Contamination is often caused by enthusiastic chain lubing, oil, or debris picked up when riding in wet conditions.
An easy fix for this is to clean your brakes with rubbing alcohol or one of the many brake cleaners you can buy.
Over time, brake blocks can become glazed over or worn out and need replacing. If they’re glazed, remove any small pieces of grit that have accumulated and use sandpaper to smooth the top layer.
After cleaning your brake pads, it makes sense to do the same to your wheel rims.
Most aluminium rims have a rough machined surface to boost braking performance. A build-up of dirt or a worn rim can adversely affect braking efficiency, so scrub them to remove any residual dirt.
Your brake pads could become misaligned over time due to wear and tear.
Brake pads need to be set up with a small amount of 'toe-in', which allows the front edge of the brake pad to touch the rim just before the heel of the pad.
Also, ensure that the rim brakes and brake pad touch each other and neither touch the tire.
After you’re done with the installation, give your brakes a check. If you still have squeaky bike brakes, keep adjusting the pads until they brake smoothly. Then your bike is ready to ride.
How to stop squeaky disc brakes
You won’t be surprised to hear that the causes of noisy disc brakes are pretty much the same as rim brakes; you just deal with them differently.
This is the most common reason, so be careful when you use spray lubricants on your bike. In fact, to be on the safe side, it’s best to avoid them altogether.
The best way to clean your rotors or wheel rims is with a specific (oil-free) disc brake degreaser.
If your calipers are misaligned, or your rotor is bent, your brake pads will rub as you ride. To check, lift your wheel off the ground and give it a spin. If it doesn’t rotate freely and comes to a stop, you’ve just found the culprit.
The first step is to ensure your wheel is correctly seeded in the dropouts of the fork or chainstay. This may be down to a quick-release skewer that doesn’t thread into the frame or an improperly installed one.
If that doesn’t stop it, check the alignment of the caliper:
- Slacken off the caliper bolts to loosen them
- Depress the brake lever to centre the caliper over the rotor
- Still pulling the brake lever pulled, tighten the caliper bolts equally
If neither of those works, it may mean that your brake rotor is bent. When you look down through the caliper and spin the wheel, you should see when the brake pad meets the rotor (where the rotor is bent). You can delicately bend it back into place with an adjustable spanner or rotor tuning fork (if you have one).
Glazed Brake Pads
A new rotor or brake pad must be broken in properly. If not, you could cause your brake pads to glaze over. This will reduce their ability to slow you down and (you guessed it) create a horrible screech.
To prevent this from happening, break them in (no pun intended) by avoiding overly aggressive braking. Gently pull them on a few times until the brakes become more powerful, as some brake pad material evenly covers the rotor.
If you’re reading this too late and your pads are already glazed, remove them, and use sandpaper to scuff the pad’s surface.
Water and Heat
These two are not best friends with disc brakes. When you ride through a puddle, your brakes may begin to squeal. Don’t panic, as this is usually temporary.
As for heat, this will cause squealing if you consistently brake for extended periods (usually when you’re riding downhill).
A good technique for riding long descents in warm conditions is to stagger your braking. For example braking for a second then releasing for a second. This allows air to circulate your brake discs and cool your pads.
If you think your brakes have overheated, check for discoloured rotors. This indicates they should be replaced.
The final word
Now you know how to prevent your bike’s brakes from squealing. It may be trial and error to find the cause, but if you follow our tips, you’ll soon eradicate that annoying noise. Bookmark this article for future reference. And take a look at this video by road.cc, which takes you through some of the points we’ve mentioned above.