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Shuddering brakes on GTR

Godzilla32
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Godzilla32 Veteran

Godzilla32

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Posted

Hey im having trouble with shuddering brakes. I had the 4 original ones machined for RWC and then after one nite out after hard braking they began to shudder. After this i bought a set of brand new (undrilled) stock front discs as they were very cheap, thinking it would solve my problem. And it did for awhile but i still notice a very slight amount of shudder at times normally only when going quite slow. I've had my original discs re-machined since and thinking to try them again. What else could be causing this shudder? Can it be the pads wearing the discs badly? They are stock pads.. Any ideas?

Thanks guys,

Deren

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GTRgeoff Grand Master

GTRgeoff

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Posted

At a guess I'd say that you completed one of your big stops and left your foot on the brake at a light. Maybe even more than once.

This allows the pad material to propagate through the disc upsetting the grain structure and the wear characteristics.

Alternatively it can cause a differential cooling rate allowing some areas of the disc to cool at a rate wherby cementite forms, which a form of steel that is tougher and more resistant to wear. What then happens is some parts wear faster than others and you get pedal shudder.

Try the originals and see how it goes. It may not be too bad.

Just remember to have time to run a cooldown after hard braking periods and don't use the handbrake to park if the brakes are still really hot. If you are doing it on the street it's only a matter of time before something goes wrong, so come to the racetrack with us and go fast responsibly.

r33GTS-t-200kw Enthusiast

r33GTS-t-200kw

Posted
Posted

whenever i do machining i either replace the pads or re-surface them on a huge ass drop saw grinding disc and file the edges so they are not sharp to make sure they dont squeel

Could be the problem if ur pads are like bendix ultimates or a hard make up of pad they would still feel yucky

my 2c.

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