Rotor Thickness Variation
Variations in rotor thickness will cause pedal pulsation, noise, and shudder. Position the micrometer approximately 1" (25.4 m) from the outer circumference and measure rotor thickness at 6 to 12 points around the rotor face. See Fig 1. Thickness should not vary by more than 0.0005" (0.013 mm) from point-to-point on the rotor. Machine or replace the rotor as necessary.