<E36> Brake rotor disc Q

[Sumant Jayaraman <sumant.jayaraman@xxxxxxx>]

We have a 94 325i. Over the last month or so, it has developed an
ever-so-slight shimmy in the steering under braking.

Now, for what could well be an oft-repeated newbie question:
What is the accepted wisdom regarding turning the brake rotors down to
true? (I've heard it is a no-no for the soft stuff BMW uses.) And if it is
indeed kosher to turn them down, can somebody please educate me on the min.
acceptable rotor thickness?

Thankyou

Sumant

94 325i, wa-wa-warping rotors
90 240sx, new rotors

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