A simple guide from Dan’s Bike Workshop

Squeaky disc brakes… easily one of the most annoying things on any ride. You’re cruising along the Tarka Trail, enjoying the peace and quiet, and suddenly your bike sounds like a battered shopping trolley. The good news? Most of the time it’s fixable — and the causes are pretty straightforward.

Why Disc Brakes Squeak

1. Contamination (the most common cause)

Contamination happens when oil, fluid, cleaning products, chain lube, road grime, or any sort of liquid ends up on your disc or pads. It only takes a tiny bit to ruin the braking surface, and once it’s there, it causes that high-pitched squeal we all hate.

Contaminated pads also lose braking power, so it’s not just annoying — it’s unsafe.

2. Glazing (happens more than people think)

Pads and discs can become glazed when brakes aren’t used properly. If you only brake lightly or don’t use them often, the pads can develop a shiny, glass-like finish. This smooth surface reduces grip on the disc, which leads to squeaking and reduced stopping power.

You’ll normally notice a shimmer on the disc or a smooth sheen on the pad — that’s glazing.

Before You Try Fixing Anything: Check for Leaks

If you’ve got hydraulic disc brakes, always give the calipers a quick check first. A leaking caliper (DOT fluid or mineral oil) will constantly contaminate your pads, meaning the squeak will keep coming back no matter what you do.

Fix the leak first — then fix the squeak.

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How to Fix Squeaky Disc Brakes

Here are all the common fixes, in order from quickest to most effective.

1. Use a Disc Brake Degreaser

This is usually the fastest and easiest fix.

• Use a specific disc brake cleaner (don’t use general degreasers on pads).
• Spray the cleaner over both your disc and pads.
• Wipe the disc thoroughly afterwards.
• Let everything dry fully.
• Test the brakes.

If contamination was mild, this often sorts it. We recommend Disc Brake Cleaner from Muc-Off

2. Sand the Pads and Disc

If your pads are glazed or the disc surface is too smooth, sanding can help.

• Use rough sandpaper (80–120 grit works well).
• Lightly sand the pad surface until the sheen disappears.
• Lightly sand the disc to create a bit of bite.
• Always sand after degreasing, not before.

3. Burn the Pads & Disc

This one works… but please be careful. Heating the pads can burn away oil contamination, especially from stubborn DOT or mineral oil residue.

• Hold the pads with pliers.
• Use a blowtorch or strong heat source.
• Heat until the surface looks dry and slightly matt.

It can be effective — just not the safest option, and not one I recommend unless you’re confident.

4. Replace the Pads and Disc (the most effective fix)

This is the one nobody wants to hear, but after years of repairing brakes, I can safely say it’s the only guaranteed solution when contamination is bad.

Cleaning can help, sanding can help, even burning can help… …but once oil soaks deep into a pad, it’s very hard to remove completely.

Replacing both the pads and the disc gives you a fresh start and perfect braking again. When we do this for riders, we always check the calipers first — because if they’re leaking, you’ll waste money replacing parts only for the problem to return.

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So… Should You Try Fixing Them or Just Replace Them?

You can fix squeaky brakes using the steps above, and in many cases it works. But sometimes it’s best to save your sanity, stop wasting time, and start fresh with new pads and a clean disc.

If you’re not sure what’s causing your squeak — contamination, glazing, or leaks — feel free to pop me a message. I’m always happy to take a look and point you in the right direction. If your unsure if its an obvious fix pop along to your local bike shop in Braunton.