Brake shudder?

[liljegren]

Suffering a bit of brake shudder on my Postie at the entrance to turn 1 at Hampton. Dialed the front discs today, .15mm and .2mm runout on the discs. Is this enough to be a problem, or am I looking in the wrong place?? Thanks, Matt.

[OddDuck]

Might be... if they're floating discs you could just be looking at the disc moving on the rivets. Check thickness, go around the circumference with a micrometer.

The other thing it could be is a slight bend in the disc, if it took some force to get the calipers off for servicing. If the disc is fixed directly to the hub then you've already checked for that with runout, if it's floating then you'll have to work something out. Probably take off and check with a surface table / feeler gauges etc.

For what it's worth (probably not much) I had a bit of brake judder a while ago but it disappeared after my one and only track day... I blued the discs and they were fine after that. I suspect that I'd slightly bent one while pulling calipers off, the wave pattern discs aren't very strong side to side.

Hope this helps.