I used to make large roller bearing races up to 26.5 inches in diameter.We had a problem one time after heat treating and final grinding the races grew .030".We started after that freezing the races in liquid nitrogen after heat treat,.
If you replace rotors again I would invest in cryro treated rotors.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran, deutschland deutschland uber alles uber alles in der welt