Checking Front Brake Disc - Minimum Thickness

Information 

• Replace brake discs once the maximum wear dimension has been reached. 
• Re-machining of brake discs is not permitted! 

As the pressure force of a brake piston on the brake pad varies in magnitude, different areas of wear arise on the friction surface. The brake disc can basically be divided into two areas of wear:

-A-  Outer and inner wear area.

-B-  Central wear area.

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Wear areas A and B

The central wear area -B-  is the area with the highest degree of wear.

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Wear area B

Measure the brake discs using a suitable micrometer at least three different places (-A, B, C-  ), offset by 120°.

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Measurement points for brake disc thickness