Since Lot of friction is involved on the Braking. The rate of wear on Brake disk will also increase. So the manufactures refer the minimum thickens on each type disk which are been installed. For the safety reasons involved in the riding its better we check the brake Disk thickness periodically!
Tool You Need : a Screw Gunge
Note: How to use a screw gauge?
How to Use a Screw Gauge | eHow.com

Step 1: Keep your bike on stable Ground. Elevate your Bike to certain height so that you can freely rotate the wheel.

Step 2: Check for the Minimum Thickness of the disk which is noted on disk itself. In case of R15 is 3.5mm

Step 3: Start taking measurements! take the measurement from different areas of the disk for prompt and accurate checking.



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