Piston: Testing and Inspection

Checking pistons and cylinder bores









Repair Stage Piston Cylinder bore dia. tolerance group
(mm) (mm) code


Standard size 99.980 100.000 0
99.990 ± 0.005 100.010 ± 0.005 1
100.000 100.020 2


Oversize 1 100.480 100.500 I 0
100.490 ± 0.007 100.510 ± 0.005 I 1
100.500 100.520 I 2

Checking pistons
Measure approx. 61 mm from piston crown, 90° offset from piston pin axis.

Checking cylinder bores
Measure approx. 61 mm from upper edge of cylinder bore, transverse to engine block. Mount lower crankcase section and tighten bolts to specified torque for measuring.