High speed brake judder -JCW GP

[jackpe]

Hey guys, I just bought a 2006 JCW Works GP. The seller deliberately failed to mention a high speed brake judder coming from the front so only realised on way home. Any idea what it could be? I've checked and the pads are worn evenly, discs look fine and calipers are not sticking. So either I have a warped disc or something else. The discs are not discoloured so can't see they've been overheated. The judder comes up into the steering wheel which visibly shakes. From about 60mph onwards. The faster the worse it gets. Otherwise it seems to drive perfectly with no knocks or shakes, only judders under braking

[rigga]

Excessive disc run out, might look ok to the naked eye, but warped.

[jackpe]

Yes I know that's one of the options.. Just wonder how it happens since there are no signs the brakes were used hard

[rigga]

I replaced my front discs for exactly the same issue, upon inspection there was no discoloration or sign's that they were knackered, new discs cleared the issue, as I said, to the naked eye they were fine, though the use of a dti would have revealed the issue whilst they were still fitted.

[CarsOrBikes]

It's a GP so more than likely has worked the brakes, does the judder continue or is it very brief as applying the brakes then ceases? If so check the front suspension lower arm rear bushes as they cause a momentary shudder on brake application, often accompanied by enhanced tramlining. Otherwise new discs required. Inexpensive if standard GP brakes as they're the same as JCW gen 1.

[Leins]

I replaced mine last year, and there are actually two types of R53 JCW discs. I went for the slightly more expensive grooved ones (on the right in pic), and along with uprated fluid find them perfect for road use

[jackpe]

Hey guys, replaced the discs but kept the pads as they looked new so now bedding in is taking a while longer than normal... Not done any really hard braking but so far the issue ha not reappeared.. Fingers crossed.

[jackpe]

Hey guys.. I've made a little video on what I think of the Mini so far.. love it! Going to be hard to sell on already but thats how the 12 cars thing works..!

12 Cars - Mini Cooper Works GP MK1