Brakes

[silversix]

Has anyone warped their discs?
I know it sounds silly, but mine have started juddering. It's been back to the dealer who have said that there's nothing wrong. (but trust me, you can feel it, and see the rear wing vibrating about 1 inch from side to side). Just want to see if anyone else has had any trouble, before taking it back to the factory (day off work and long trip) to get their opinion.

Cheers

Adrian

[ThatPhilBrettGuy]

Go out and find somewhere safe to do a few (5-10) big nose-on-the-windscreen 100-5MPH stops. Usually sorts it out.

[Matt_FP]

You've got a build up of friction material on the disc.

To remove it you can either remove the discs and skim them or (the cheaper, easier and more fun option) do five or six very hard stops from post 100mph.

Best Regards
Matt

[paulcundy]

this is another of those myths - "warped discs". As the others have said its build up of material on the disc surface. Often happens, Get rid of it by using the brakes.
Regards
Paul C

[joust]

paulcundy said:

this is another of those myths - "warped discs". As the others have said its build up of material on the disc surface. Often happens, Get rid of it by using the brakes. Regards Paul C

www.stoptech.com/whitepapers/warped_rotors_myth.htm

J

[silversix]

Matt_FP said:

You've got a build up of friction material on the disc. To remove it you can either remove the discs and skim them or (the cheaper, easier and more fun option) do five or six very hard stops from post 100mph. Best Regards Matt

I'll try it, but not holding my breath, as I've used the brakes quite hard and they haven't got any better.


Oh and you CAN warp discs ask any EVO owner....... I went through 3 sets in 6 months.....

[paulcundy]

silversix said:

Matt_FP said: You've got a build up of friction material on the disc. To remove it you can either remove the discs and skim them or (the cheaper, easier and more fun option) do five or six very hard stops from post 100mph. Best Regards Matt I'll try it, but not holding my breath, as I've used the brakes quite hard and they haven't got any better. Oh and you CAN warp discs ask any EVO owner....... I went through 3 sets in 6 months.....

Was that before you heard about this alternative explanation? Perhaps they weren't warped at all? I can't imagine any dealer turning you away.

I had several sets of "warped discs" that I couldn't afford to replace that for some inexplicable reason used to get better over time. Only when I read the link on Justin's mail did I realise what was going on.
Now when I get the brake judder I know what to do.
Regards
PauL C

[jmg944t]

I resolved this problem with a wire brush on a drill. I spent 1 minute on each braking surface and the problem went away. If the heavy braking doesn't do it give that a try with a medium brush and medium to light pressure.

[silversix]

Ok, been out for a "quick spin".

I now have:

a. a big grin.
b. a lot of dead insects on my newly Zymol'd car
c. brakes that still judder
d. a brake pedal that nearly hits the bulkhead.....

However, i can "see" deposits on the discs. I'll try with a wire brush tomorrow, and order some SRF, or C-tech fluid (and possibly a set of F2 pads) from Alan at Questmead on Tuesday.

BTW where is it safe to jack an M400?

Thanks for the advice everyone.

Adrian

[caccobra]

silversix said:

BTW where is it safe to jack an M400? Thanks for the advice everyone. Adrian

On a flat surface........There are 4 points that are easily identified if you look under the car. They look like round steel buttons where the aluminum pans join. One behind each front wheel and one in front of each rear wheel. Suggest using a flat wood block or rubber insert and not just the steel cup usually found on a floor jack. You don't want to mess up those nice aluminum pans.....You'll need a low profile floor jack too.

Craig

[domcross]

I hate to disagree with the esteemed Nobility but I had warped disks on my M400. In a nutshell, I had the same symptoms as you and took all the advice on hard barking session and a wire brush. Nothing worked. I went to Rockingham and the workshop team immediately tested the car and told me that I had a warped set of rear disks which they duly replaced at the circuit in the first hour.

Bob told me that they sometimes get a 'duff set' from the manufacturer that are simply not flat and cause the vibration.

I'm no grease monkey but that's what Bob and the engineers told me.

Good luck!

Dom.

[chillidog]

domcross said:

Bob told me that they sometimes get a 'duff set' from the manufacturer that are simply not flat and cause the vibration.

Then surely *you* didn't warp them, so the myth still applies as it was a manfacturing defect.

Point take though - if the hard braking doesn't work get them checked to see if they were made right in the first place.

[silversix]

Wheels off, and FRONT discs cleaned with wire brush. Still vibrates when braking.
there isn't much vibration through the wheel though, or the pedal come to that, so wondering if it could be the rears? When I did the EVO's, you could feel the pedal pulsing, and the steering vibrating. I feel a trip to the factory coming on.
BTW, if it is the rears, and they weren't made correctly, were they covered by waranty?

Thanks

[domcross]

silversix said:

BTW, if it is the rears, and they weren't made correctly, were they covered by waranty? Thanks

They sure were