2. Rotate the disc slowly so that the entire surface can be viewed on both sides. Light scoring in the area where the brake pads meet is acceptable, but if there are deep scores, the disc must be replaced. The only alternative is to regrind the surface of the disc, but the thickness of the disc must not be less than the specified minimum thickness.
3. If the disc is suspected of being distorted, this can be checked by placing a gauge at any convenient point and slowly rotating the disc, or by using feeler gauges, measure the clearance at several points around the disc. Measure in the centre of the pad coverage area. If the obtained dimensions are close to the specified maximum or greater, the disc must be replaced. But first, the condition and adjustment of the hub bearings must be checked - see Chapters 12 and 13 from Section 10.
4. Check the disc for cracks, especially around the holes, and any other signs of wear or damage. Replace the disc if necessary.
5. If one of the brake discs is worn or damaged, both discs must be replaced at the same time to ensure smooth braking.
6. Since the rear brake discs are integral with the rear hubs, their removal requires the removal of the hub bearings. When installing, the bearings must be assembled and adjusted. See Chapters 12 and 13 from Section 10.
7. When installing a new brake disc, use a suitable solvent to remove the preservative.
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