In this case, it is necessary to use a special caliper, or a regular one, placing hard pads (coins) on both sides, since a rib (bead) is formed on the edges of the disk during operation. Measure at several points. Subtract the thickness of two pads from the caliper readings. The disk parameters must meet the requirements of the technical characteristics of the brake system (see above). Otherwise, grind the disks or replace them with new ones.
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