Vibration under braking.......

[quattrosteph]

I've been on track recently and did make sure i cool down the brakes at the end of each session.

I now have some vibrations under braking at little speed when the brakes are cold, no vibrations when they are hot

Did check the pads and they are cracked in the middle, all of them (RS6 brakes) Will replace them with new ones to see. Are cracked pads can cause vibrations ??

Did check the discs and they look fine, not warp.

[buzzard]

yo quattrosteph
looked well on the track mate
you could have warped a disc , it doesn't take much.
you would need to check the disc run out with a dial gauge to check how bad this is.(most engineers could fix you up with one)
if it is now there constantly on cold i dont think there is much chance of it going.
my discs vibrate and go blue in places after a good hard drive but go ok again after a few days.
hope it goes away

[quattrosteph]

Warped disc........BALLS!!!!!!!!!!!!!!!!

[derdle]

If it's only slightly warped....is there a possibility that it could be skimmed at a machine shop?

Paul

[dace]

Warped disc........BALLS!!!!!!!!!!!!!!!!

Oh dear.......that's the danger of track days

[quattrosteph]

Yeh but brakes had only 2000 miles......If fitted on RS6 they should be up the job on an RS4 B5 isn't it ??? Brand new set and after a trackday (in novice ) discs are fucked ??????? I don't think it is right !!

[flashyg]

Turn of tc/esp, as this will be applying the brakes all the time if you are chucking the car about.

[jeffw]

More likely to be either pad deposits or the pads themselves. If the discs are warped you would find it gets worse when it is hot.....If the pads are cracked you may well get the vibration your experiencing

[Marlon]

I agree with Jeff, definatley pad material deposited and bonded to the disks.

Couple of high speed braking runs required to try and clear it from the disks.