Thread: Warped rotors
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      12-18-2008, 07:57 PM   #21
consolidated
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Your rotors are likely fine, a few days of moderate street use should take the material off, if not get more abrasive track pads to clean up the rotors, you'll not likely find anyone willing to 'turn' two piece rotors, they'll come out of the lathe in worse shape.

I get this condition everytime I go to the track with PFC01 pads. Try to warm your brakes up and avoid slamming up against ABS when they're cold.

http://www.stoptech.com/tech_info/wp...rakedisk.shtml

Quote:
Myth # 1 – BRAKE JUDDER AND VIBRATION IS CAUSED BY DISCS THAT HAVE BEEN WARPED FROM EXESSIVE HEAT.


The term "warped brake disc" has been in common use in motor racing for decades. When a driver reports a vibration under hard braking, inexperienced crews, after checking for (and not finding) cracks often attribute the vibration to "warped discs". They then measure the disc thickness in various places, find significant variation and the diagnosis is cast in stone.

When disc brakes for high performance cars arrived on the scene we began to hear of "warped brake discs" on road going cars, with the same analyses and diagnoses. Typically, the discs are resurfaced to cure the problem and, equally typically, after a relatively short time the roughness or vibration comes back. Brake roughness has caused a significant number of cars to be bought back by their manufacturers under the "lemon laws". This has been going on for decades now - and, like most things that we have cast in stone, the diagnoses are wrong.....

In fact every case of "warped brake disc" that I have investigated, whether on a racing car or a street car, has turned out to be friction pad material transferred unevenly to the surface of the disc. This uneven deposition results in thickness variation (TV) or run-out due to hot spotting that occurred at elevated temperatures....