Squeaky Hydraulic Disc Brakes

[Thomk]

Can I stop them squeaking quickly and easily? If so how? Thanks!

I need to use the bike in about 30 minutes!

 

[ScotiaLass]

Could be a number of things!
Have you cleaned the discs recently?
It could also be that you need new pads. If you've recently put new pads on, it could be that they are bedding in or, as I found recently, they are just noisier than my last set (due to being semi-metallic and sintered). But they stop great so I'll live with the noise!

 

[Thomk]

I haven't changed the pads recently. Is there a simple maintenance thing I can try?

I haven't used this bike for a couple of years.

 

[ScotiaLass]

Clean the discs...if you haven't got a specific disc cleaner then something like Muc Off and rinse well and dry them.
Don't touch the discs with your hands.
The bike may need a general clean and service if it's been sitting for a while, so you may not be able to rectify the noise immediately.

 

[Thomk]

Thanks!

 

[Supersuperleeds]

Get yourself some Isopropyl Alcohol and wipe the rotors - it is miracle stuff for squeaky discs, credit to @Cubist for this tip

 

[Torvi]

if you have vodka in your fridge you can use it to clean the discs with it, put some on a piece of rag and wipe your discs with it :P

 

[Thomk]

Thanks all. I've gone a bit wild and bought some disc brake cleaner!

 

[Globalti]

If you are getting a nasty juddering squawk as the bike rolls to a stop, the pads and discs are contaminated with oil or brake fluid. Put the pads in the dishwasher and clean the discs with IPA or glass cleaner.

 

[Thomk]

I've decided to change the pads as I've never done in and they're cheap.

 

[Tom B]

Probably will be minor contamination and corrosion on the disks that will clean up with use.

 

[mrbikerboy73]

Put the pads in the dishwasher and clean the discs with IPA or glass cleaner.

I find London Pride works better than IPA as it has more alcohol in it

 

[raleighnut]

Very often a couple of short 'grab and release' applications of the squealing brake will cure it, but I'd do this well away from any traffic.

 

[Thomk]

I took a look at the pads on the front and they were butchered do I changed them and cleaned the discs. I'm going to do the same to the rear ones.
BTW, the new pads are rubbing slightly on the disc despite me pushing in the pads all the way back on the calliper. Will this just resolve itself as the brakes are used?

 

[Globalti]

Brake pads, especially sintered ones, can look quite ropey as the softer material wears leaving the harder bits. That's no reason to change them. If the new pads are rubbing check that the centre seam of the caliper is lined up with the disc, you can correct this by adding or removing shims between the caliper and the tabs on the frame. If that still doesn't fix the rub, just ride.

On a hydraulic brake the pads will be pulled away from the disc by the flexibility of the rubber piston seals, in which they are an extremely tight fit. They don't slide through the seals when you brake, the seals deform and then spring back to pull the pads back. As the pads wear the pistons do creep slowly through with each successive application.