What's happened to my brakes?

[Justin Cyder]

Specialised Rockhopper with Auriga Tektro pro disc brakes.

On Saturday, I was out on a big ride & we descended a steep, rocky path for about 300m under heavy rear braking. The disc did get very hot as a result. After this, I noticed the rear brakes squealing & a degree of scoring on the disc itself. I assumed I'd lunched the pads so took them off the following day only to find they look fine, plenty of meat left, but a small chunk missing from one corner of one pad.

The brakes are still squealing, so why is this & can I do anything about it?

[tigger1]

Start with replacing the broken pad

If you've scored the disks (possibly a bit of grit between pad and disc under braking) then not sure how to resolve that, but definitely give the pads a clean up with brake cleaner.

[Justin Cyder]

Good idea. PAds are a tenner a pair, so I may as well put new ones in.

[P-Jay]

You can cook pads occasionally, especially if you drag-brake, they'll have meat left on them, but the surface is cooked diamond hard so frictions drops right off, lots of noise, little actual slowing down.

[Justin Cyder]

I hear that but if anything, the braking action is slightly enhanced?? There's just a god awful racket going along with it. I'll stick a pair of new pads in & see how we get on.

[Gren]

Clean the rotors with isopropyl alcohol and sand down the pads. Then try running them in again by doing a few hard stops without locking them up. Usually sorts out most things

[Digga]

Justin Cyder said:

I hear that but if anything, the braking action is slightly enhanced?? There's just a god awful racket going along with it. I'll stick a pair of new pads in & see how we get on.

Could also have embedded grit into the pads.

If you live somewhere gritty, avoid organic pads and look at either sintered or the carbon-kevlar ones, because grit+rain = no pads very, very fast.

[gazza285]

Ditch the discs and get some cantilevers.