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MG MGF Technical - story about perforated brake discs

When noting my brakes start to make a very loud sharp noise when braking (I have this MS upgrade installed), dealer told me this is 'normal' with perforated brake discs. (he quoted story about same problem with BMW motorbikes, hello Ted!). Has to do with the discs not being 100% flat due to holes slightly deforming discs, and once the pads are 'scrubbed in', they'll start to get noisy. True or not?

Anyway, I had to pay another 400 yesterday for std maintenance plus the usual niggles. Dealer told me they are fed up with the car. "Sure she's beautiful, but it costs you a fortune to keep it running and we're fed up with it because we get the feeling we can't repair it, despite all efforts we do, coz you're quite a 'unique' customer, an oddity", he said.
"Can't you crash it?" he added...!


I have the MS big brakes and also have brake squel when
brakes are hot, although in my case I think it's coming
from the left rear wheel, maybe the back of the pad
chattering against the caliper....


Most BMW bikes are equipped with Brembo brakes and most bikes (BMW and others) use a floating disc system which compensates for any irregularities in the discs.

As for noise - with a crash hat on and the stereo going - I wouldn't know:-)

Ted Newman

Dirk - I have the EBC grooved and pitted (not drilled right through) discs, and green stuff pads. I don't get any brake squeal. Actually I thought one of the points of having the grooves/drills was that they provided multiple biting surfaces which prevents the pad from glazing, and that its the glazing of the pad that makes them squeal. Of course grit caught in there will do the same but again I would have thought the grooves/drills would sweep grit away.

Anyway mine don't and the story you are being told sounds like a convenient way of explaining away something they don't have a real answer for. It's called confuse the customer with science, or at least what sounds like science. Pretty suspect.


I run the 280mm size disc at the front and these are cross drilled also. I have no noise. If there is a pad to disc noise during heavy braking I would expect this to be a rumbling sound, that is usually generated by modern friction materials when they get hot. Loud shrieking or squealing noises are usually attributed to high frequency vibration of the pad in the caliper.

This is often cured by the application of a copper grease on the back of the pads where they contact the caliper, or better still special anti vibration pads are available (universal fitting) from any good supplier of brake parts. These are self adhesive and are cut to fit the rear of each pad. This acts as a damper to vibration and is very effective.

More and more pads are now being supplied with this material already fitted due to the upsurge in complainst of brake squeal.

Roger Parker

This thread was discussed between 31/08/2000 and 01/09/2000

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