Checking Involves The Following

Visual inspection for surface changes in the brake disc friction surfaces and wear indicators. Indication of wear: Connected surface fracture > 1 cm²-arrow- , without adding up smaller fractures → 465102 CHECKING FRONT PCCB BRAKE DISC (WEAR ASSESSMENT) .

Fig 1: Locating Surface Fracture
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Check surface roughness (Rk) of brake discs (max. 80 μm permitted) since this affects braking comfort (noises), braking behavior/pedal pressure and brake-pad service life → 465102 CHECKING FRONT PCCB BRAKE DISC (WEAR ASSESSMENT) .

Fig 2: Identifying Surface Roughness Of PCCB Brake Disc
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Check brake discs for minimum thickness -X- . The minimum brake disc thickness (e.g. Min. Th. 33.7 mm) is stamped on the brake disc hub → 465102 CHECKING FRONT PCCB BRAKE DISC (WEAR ASSESSMENT) .
Measure the brake disc thickness -X- in the area of the outer or inner friction surface track -arrows- at least three different points (-A, B, C- ) offset by 120°.

To do this, use a suitable micrometer or a brake disc gauge.

Fig 3: Identifying Minimum Thickness Of PCCB Brake Disc And Measuring Points
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Check brake discs for edge damage -see Fig 4 illustration- (damage due to improper use). → 465102 CHECKING FRONT PCCB BRAKE DISC (WEAR ASSESSMENT) .

Fig 4: Identifying PCCB Brake Disc Edge Damage Area
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