Disc Brake Squeal

[GuyBoden]

I'm new to Disc Brakes, I've bleed the hydraulic system, put in new brake pads, realigned the calipers etc.
Everything seems mechanically ok?

When I squeezed the levers very hard I get a loud squeal, which is very effective as a warning to pedestrians, but annoys some people. Personally, I don't mind the squeal.

Do I need to do something, mechanically?

 

[Threevok]

All brakes squeal
They may squeal because they are new and need to be bedded in
Or they may squeal because they are sintered pads (organic or resin ones don't seem to squeal as much but don't last as long)
Pads or discs may have become contaminated, although this is normally coupled with a lack of braking performance

If the problem persists, you may want to try a little copper grease on the rear (only) of the pads

 

[GuyBoden]

All brakes squeal
They may squeal because they are new and need to be bedded in
Or they may squeal because they are sintered pads (organic or resin ones don't seem to squeal as much but don't last as long)
Pads or discs may have become contaminated, although this is normally coupled with a lack of braking performance

If the problem persists, you may want to try a little copper grease on the rear (only) of the pads

Thanks, yes, they are new sintered pads, the discs have been degreased and cleaned, so contamination is not the problem.
If they don't stop squealing, I will just have to learn to enjoy the squeals.

 

[fossyant]

Have you bedded them in with a few hard braking sessions, but not to a full stop. My brakes only squeel on first braking if they have just gone through a deep puddle. Being on an MTB its more gritty noise until the disks are wiped clean by the pads.

 

[Threevok]

In the wet they even worse

There can also a difference in brake pad manufacturers too

I find the Avid sintered squeal a lot more than Clarkes sintered

 

[glasgowcyclist]

There's lots of good info on the thread where this post comes from: https://www.cyclechat.net/threads/another-noisy-disc-brake-thread.200324/#post-4272154

 

[Crankarm]

All brakes squeal
They may squeal because they are new and need to be bedded in
Or they may squeal because they are sintered pads (organic or resin ones don't seem to squeal as much but don't last as long)
Pads or discs may have become contaminated, although this is normally coupled with a lack of braking performance

If the problem persists, you may want to try a little copper grease on the rear (only) of the pads

Don't put copper grease anywhere near disc brakes. See Ed China's video on YT as to why.

 

[Crankarm]

I'm new to Disc Brakes, I've bleed the hydraulic system, put in new brake pads, realigned the calipers etc.
Everything seems mechanically ok?

When I squeezed the levers very hard I get a loud squeal, which is very effective as a warning to pedestrians, but annoys some people. Personally, I don't mind the squeal.

Do I need to do something, mechanically?

The squealing could be down to a number of things. Crappy brakes in the first place. Contaminated braking surfaces, pads or disc. Misaligned calliper, pads, or disc or combination of all three. You don't say what make of brakes, disc and pads you have. I have Shimano SLX disc brakes and they have never ever squealed once. They are strong and silent. I have used both organic and sintered pads. Consult YT on aligning the calliper and pads. There are some good tutorials to show you how to do it properly. And don't put any copper slip anywhere near your disc brakes.

 

[Kajjal]

The most likely answer is the rotors, pads and calipers are contaminated.

Rotors and callipers normally clean up fine with disc brake cleaner. With the pads often they clean up fine but not always. Don't put new pads in until everything else is clean

Another answer is the pads are worn so far down you are braking on the solution that attaches the actual pad to the backing plate. This will contaminate everything as soon as you brake.

 

[Rooster1]

http://road.cc/content/feature/188504-how-stop-your-brakes-squealing

 

[Rooster1]

Perosnally, I like squeal

 

[GuyBoden]

Many thanks.