Front Brake Disc Thickness Check
1. Measure the disc thickness with a micrometer at eight points offset by 45 degrees and 10 mm from the edge of the disc (pic. 14.14).
Pic. 14.14. Measure the disc thickness with a micrometer at eight points offset by 45 degrees and 10 mm from the edge of the disc
Brake Disc Thickness:
- Nominal value: 18.0 mm.
- Allowed value: 16.4 mm.
2. Difference in disc thickness (at least 8 locations) should be no more than 0.015 mm between each of the measured points.
3. If the thickness is out of specification, the brake disc must be replaced or reground.
Checking brake disc runout
4. Unscrew the caliper support and secure it with a wire.
5. Check the brake disc surface for pits, cracks and rust. Thoroughly clean the disc and remove all traces of corrosion.
6. Attach a dial gauge 5mm from the edge and measure the disc runout (pic. 14.15). Valid value: 0.06 mm or less.
Pic. 14.15. Checking brake disc runout