How to stop bike brakes from squeaking

Do your brakes squeal like a pig when you apply them? Maybe you’re wondering If you can stop it. In this article we are going to be discussing the reasons behind squeaky brakes and more importantly how to stop bike brakes from squeaking.

What are the main causes of squeaky brakes?

There are a number of things that can cause squeaky brakes. The reasons are listed in this article so that you can try and identify the cause and (hopefully) move onto the next step of how to stop bike brakes from squeaking. 

Embedded aluminium 

Over time tiny shards of aluminium from the rim can embed in the rubber. This can cause the brakes to squeak and accelerate rim wear. It is possible to pick out the bits of aluminium, but replacing the pads is quicker and ensures that there are no bits of metal left in the pad. 

Contamination

Over time rubber residue from the pads, aluminium dust from the rims and oil from the chain, build up on the rim and can cause squeaking.  Give your rims a really good clean with isopropyl alcohol. Squirt the rim and then clean with a clean dry rag or clean up roll. 

Brake pads in poor condition

Over time the pads can become glazed and very hard. You can sand down the braking surface of the pads or replace them.

Pad wear

Over time the rubber compound on the pads wear. If the pads are not replaced regularly then the rubber compound may wear completely leaving an aluminium body exposed. When the brakes are applied, the aluminium body that supports the pads rubs on the aluminium rim causing a loud noise.This wears the rim really quickly. If this is the case then replacing the pads is the only solution. It is also a good idea to take a trip to your local bike shop to check the condition of the rims.  

Pad position

One of the reasons that rim brakes squeak is because of slackness in the caliper bushings or too much flexing in the brake arms or pads. It’s caused by the friction of the brakes against the rim flexing the pads or brake arms, which then slip back, grab, slip back, grab, etc. and the pad isn’t grabbing the rim evenly in one action. This happens at a very high speed and the vibrations cause noise. This is mainly out of the range of human hearing, but sometimes results in an audible squeal.

Rain

Because there is a very small amount of lubricant in water, brakes can sometimes squeak in the rain.  This should stop when they dry out.

How to stop bike brakes from squeaking

In this section we are going to be covering the different methods on how to stop bike brakes from squeaking. First, check the pads for embedded aluminium, contamination, condition and wear. Now decide whether you are going to try and sort out the pads or just replace them.Here’s  a bit of advice from an old hand; it is always better to replace the pads unless you are desperately skint. By doing so you know that you’ve not missed anything. The tiniest shard of metal means that your brakes will probably still squeal.. Next clean your rims with isopropyl alcohol, and no drinking it! Don’t be tempted to use any sort of degreaser as soapy residue will reduce your stopping power.If you still have problems then you need to adjust the position of your pads.

Poor pad position can increase the vibration of the brake caliper, which leads to squeaky brakes. Adjusting your brake pads so that they hit the rim evenly in one action can reduce the noise caused by the high speed vibrations created by the caliper flexing. The braking force rotates the brake shoes slightly  so the back presses harder than the front. By adjusting the brake pads so that the front of the pads hits the rim very slightly before the back of the pad, you can sometimes reduce the uneven grabbing/flexing action and stop the noise.  This is called “toeing in”. To do this: 

  1. loosen the nut holding one of the brake pads in place, but do not remove completely.
  2. Now the brake is loose, slip a thin piece of card about half way between the back of the pad and the rim.
  3. squeeze the brake lever with the card in place and retighten the brake bolt making sure that the brake pad isn’t twisted or touching the tyre.
  4. Repeat the process with the other brake pad.

Unfortunately there is no guarantee that toeing in will stop squeaking. If it doesn’t then try setting the pads with negative toe in, that is the back hitting the rim first. Be patient. If you have new pads, a clean rim, dry weather and you keep adjusting the positions of the pads your reward will be silent and smooth stopping.

How to stop bike brakes from squeaking

First, check the pads for embedded aluminium, contamination, condition and wear. Now decide whether you are going to try and sort out the pads or just replace them. Here’s  a bit of advice from an old hand; it is always better to replace the pads unless you are desperately skint. By doing so you know that you’ve not missed anything. The tiniest shard of metal means that your brakes will probably still squeal.. Next clean your rims with isopropyl alcohol, and no drinking it! Don’t be tempted to use any sort of degreaser as soapy residue will reduce your stopping power. If you still have problems then you need to adjust the position of your pads.

Poor pad position can increase the vibration of the brake caliper, which leads to squeaky brakes. Adjusting your brake pads so that they hit the rim evenly in one action can reduce the noise caused by the high speed vibrations created by the caliper flexing. The braking force rotates the brake shoes slightly  so the back presses harder than the front. By adjusting the brake pads so that the front of the pads hits the rim very slightly before the back of the pad, you can sometimes reduce the uneven grabbing/flexing action and stop the noise.  This is called “toeing in”. To do this: 

loosen the nut holding one of the brake pads in place, but do not remove completely.
Now the brake is loose, slip a thin piece of card about half way between the back of the pad and the rim.
squeeze the brake lever with the card in place and retighten the brake bolt making sure that the brake pad isn’t twisted or touching the tyre.

Repeat the process with the other brake pad.

Unfortunately there is no guarantee that toeing in will stop squeaking. If it doesn’t then try setting the pads with negative toe in, that is the back hitting the rim first. Be patient. If you have new pads, a clean rim, dry weather and you keep adjusting the positions of the pads your reward will be silent and smooth stopping.

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