Deposits on Brake Discs After Track Day

[RichB]

Hi Guys
Following my track day this weekend I noticed the following on the brake discs. The discs are Brembo HCs and the pads are Carbone Lorraine RC5+. Any ideas what this could be? I'm guessing the pads have over heated? I will be taking the pads off to inspect at some point soon but thought others may have had similar?

Deposit on Brake Disc by rbaldry86, on Flickr

Thanks

 

[Martin.]

Looks glazed. Does it feel raised when you touch it?

 

[Keith185]

Yeah that's from overheated pads. It's the pad material meted onto disc from the heat, normal driving will soon clear it up provided pads aren't too bad, as you've said inspect them and see how they look.

Had similar when running DS2500's. Have you got any brake ducts fitted or look at running shorter stints out on track.

 

[JamesBryan]

RC5's are good for upto 800-1000 degrees i'm sure.

I doubt you've got them that hot.

 

[RichB]

I haven't touched the discs yet to see if it raised.

No ducts installed and I had two stints where I was out for about 30mins as I got carried away! Although I did run a few laps at reduced pace to try n cool things a little.

I also need to brake a bit less and carry some more corner speed! Was a little wimpy as it dried out! I'll get the pads out soon to check everything up close and probably bleed the fluid if I've overheated the pad the fluid has prob boiled (motul rbf 660).

 

[Ph1 Tom]

There's no way you'll have overheated them...1200 degrees C brakes on a Clio?!

I'd say your discs will have warped before the pads go outside of the operating temperature.

They might clean up with some road use.

 

[MarkCup]

That's pad material transferred to the disc surface, not from overheating...but from how pads are meant to work best.

Why do drag racers lay down rubber at the start line? Aside from heating their tyres up they're creating a rubber surface for their tyres to bite into. Rubber grips rubber better than it grips tarmac.

It's the same with pads...they work best once you have a nice coating of pad material all around the disc for the pads to grip onto...often looks like a bluish or purple tinge.

After the trackday when you're not beasting it everywhere they'll clear up in due course through normal braking..