Warped vented disc?
Turbo Mini Forums

I've got the Mini Sport - 8.4'' Vented Brake Caliper Kit and have a bit of s shudder under breaking.

Jacked the car up today and when you spin the drivers wheel by hand you can see the break disc isnt turning straight like on the passenger side. You can see moving side to side like its warped but I didnt think such a thick disc could have warped, especially <1500 miles.

Thinking back the issue may have been there from the first mile but then I was driving a lot slower and breaking a lot lighter, the brake kit went on a good few years before the car turned a wheel on the car!

Have I got a warped disc or another issue? The car drives very smooth so I can't imagin a bearing issue for example.

Thoughts?

http://turbominis.co.uk/forums/index.php?p=vt&tid=170151

I had a really bad wobble under braking on my old mini. Flange bolts had come loose. :$

Take off the wheel and measure the run out with a dial gauge

I seriously doubt it!

Thats not unusual - the ventilated discs on my car also warped.

ive had pad material fuse to the disc when I was was using green stuff and they got too hot..

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

Get them warm then give them a really really good stand on and get them red hot.

The evo used to be shit for it , the pad/disc get a build up of pad on them n the shake like a warped disk

rick

If you can visually notice that the disk is running out then that is it. Maybe your drive flange is not running true and warped your disc or your disc is warped for other reasons such as incorrect fitment. Checking run out of both drive flange and disc with a dial gauge will reveal the culprit. Don't waste your cash just fitting a new disc without dial gauging it as you may well just warp another disc.

loose bolts have simulated this in the past; also check there is no build up of crap between the disc and drive flange mating surfaces

Cheers chaps, i'll get the dial gauge out this evening and check everything over.

If the flange isnt running straight wouldnt I notice this during normal driving? I thought there would be some wheel wobble?

http://turbominis.co.uk/forums/index.php?p=vt&tid=170151

there may be some wobble however the clamping of the brakes would exagerate it

dial gauge on the disc, 1.8mm movement.

flange, no movement (give or take for flaky paint).

took it all apart and there was a slight gap between the flange and the disc on one side, that would be the culprit!

refitted the disk to the flange (without the gap) and i'm now getting 0.17mm movement which i'm putting down to corrosion on the very outer edge of the disk that the pads dont touch.

looks like i've damaged the calliper too where the rattling of the pads has pushed them back against the calliper surface and scored it. will take it for a test drive tomorrow.

http://turbominis.co.uk/forums/index.php?p=vt&tid=170151