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Discussion Starter · #1 ·
Very disappointed in this!

Haven't been able to perform good lap times due to this! I can't even finish one hot lap before they start shaking!

Any ideas?
 

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Shaking as in a vibration when you apply the brakes? If so, sounds like a cracked rotor. Otherwise may be an installation problem.
 
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warped rotor ?
 

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Discussion Starter · #6 · (Edited)
Mine are cross drilled 380mm 6 piston BBK's!
I carefully checked the rotors and no sign of crack!

Warped? Control Arms?

Just got the car back from dealer afer checking all bushings, mounts and "control arms". All okay!
Definitely from the brakes!

Are these rotors two piece?
Should I get new pads?
Perhaps pads are rubbing the rotors for uneven deposits?
Could pads be rubbing unevenly against rotors? Shims?

Just need some opinions to take with me to my tech!
 

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Shaking as in a vibration when you apply the brakes? If so, sounds like a cracked rotor. Otherwise may be an installation problem.
You have obviously been to the track :hihi:. I had this on my M3 track car....... rotor was cracked all the way through. Did you perform a visual inspection? You will be able to spot a crack (usually).
 

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2 piece floating rotors are very prone too vibration especially when abused properly. i.e : tracked.
 

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Discussion Starter · #9 ·
The problem in my case was that ever since getting the BBK, I have been road driving it! I only realised the problem when I took it out on track for the first time!
There is obviously something wrong cause there are other M5's that are prepped for track use with this kit! Including Vivid Racing's ( where I bought the kit from ) own M5!
 

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did the disc ever suffer from splashing waters when its hot ? that could warp the disc.
 

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Remove the discs and get them checked. You'll be able to see both sides clearly this way.

You could have them skimmed.

The problem could be with the pad compound also but this is just speculation.

I would get a second opinion on the bushes also.
 

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My Stoptechs on my M3 shake too. I have drilled rotors and I can see small cracks though. Shaved the rotors (small cracks are still there!) and got new race pads and felt better. But still, after one lap of hard braking, it starts to shake.

I think this is all caused by the heat. Should've installed brake backing plates and brake duct hose kit from the begining!
 
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Discussion Starter · #13 ·
Damn, this means I have to buy that GT3 now! I really didn't want to, but it's obvious now that I must!
Shucks!
 

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Damn, this means I have to buy that GT3 now! I really didn't want to, but it's obvious now that I must!
Shucks!
Or (1) get the BBK rotors checked and the kit properly reinstalled, or (2) go back to the stock brakes.
 
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My Stoptechs on my M3 shake too. I have drilled rotors and I can see small cracks though. Shaved the rotors (small cracks are still there!) and got new race pads and felt better. But still, after one lap of hard braking, it starts to shake.

I think this is all caused by the heat. Should've installed brake backing plates and brake duct hose kit from the begining!
Hmmmm, this is kinda worrying. I'm about to have a StopTech Trophy kit installed on my M5 next week. I don't plan on tracking my M5 since I have an M3 race car, but it still doesn't sound right. Could the (wrong) pad compound be what's causing the shake? I have the Rotora Super Challenge kit on my race car and I've never experienced any shaking, nor did I experience it when I had Brembo's on the race car.

Anyone ever experience these shaking symptoms with StopTech's on the street?
Ahmed, what pads were you running at the track?
 

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Get new rotors...torque wheels properly, install rotors correctly...
 

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Hmmmm, this is kinda worrying. I'm about to have a StopTech Trophy kit installed on my M5 next week. I don't plan on tracking my M5 since I have an M3 race car, but it still doesn't sound right. Could the (wrong) pad compound be what's causing the shake? I have the Rotora Super Challenge kit on my race car and I've never experienced any shaking, nor did I experience it when I had Brembo's on the race car.

Anyone ever experience these shaking symptoms with StopTech's on the street?
Ahmed, what pads were you running at the track?
On the streets everything seems ok. It's on the track where it starts to shake after massive braking and crazy-like driving! And you might be right, wrong pads might be the problem.

Get new rotors...torque wheels properly, install rotors correctly...
^This definitely will take care of the problem!
 
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Damn, this means I have to buy that GT3 now! I really didn't want to, but it's obvious now that I must!
Shucks!
You'll enjoy the track if you do that! The M5 is a heavy car and going around the corners is a little hustle if you know what I mean!

But you gotta keep the beast.
 

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Ahmed, that sounds like pad material being imprinted on the rotors. You need to bed-in your brakes all over again. It also means the pads cannot withstand the high stress/heat your putting on your brakes. What pads are you running the original Stoptech pads that comes with the bbk?
 
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Discussion Starter · #20 ·
Thanks guys!

My tech had a look at them today and said it's the rotors! I said how? He said that's just the characteristics of them! I didn't buy that answer, it doesnt convince me and I'm not gonna bother!

I've asked VIvid to send me fresh StopTech pads. Gonna have the rotors cleaned again, pads installed and bed them in all over!

gasterus, I would have thought a few laps around the track with a cooling down lap would have been sufficient bedding in procedure wouldn't it? Like ///Power said, street driving was fine, only when they get hot, they shake like nuts! ( not my nuts, my nuts don't shake cause of the hot weather LOL )
 
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