Honda CBR125R Owner's Manual page 219

Check the top of the cylinder for warpage with a
straight edge and feeler gauge across the stud and
bolt holes.
SERVICE LIMIT: 0.05 mm (0.002 in)
PISTON/PISTON RING
Check the piston for cracks or other damage.
Check the ring grooves for excessive wear and car-
bon build-up.
Measure each piston O.D. at a point 6.5 mm (0.26 in)
from the bottom and 90° to the piston pin hole.
SERVICE LIMIT: 56.67 mm (2.231 in)
Calculate the cylinder-to-piston clearance. Take the
maximum reading to determine the clearance (Cyl-
inder I.D.:page 9-6).
SERVICE LIMIT: 0.09 mm (0.004 in)
Measure piston pin hole I.D.
SERVICE LIMIT: 13.045 mm (0.5136 in)
Measure the piston pin O.D. at three points.
SERVICE LIMIT: 12.70 mm (0.500 in)
Calculate the piston-to-piston pin clearance.
SERVICE LIMIT: 0.08 mm (0.003 in)
Inspect the piston rings for smooth movement by
Always replace the
rotating them. The rings should be able to move in
piston rings as a
their grooves without catching.
set.
Push in the ring until the outer surface of the piston
ring is nearly flush with the piston and measure the
ring-to-ring groove clearance using a feeler gauge.
SERVICE LIMITS:
Top:
Second: 0.09 mm (0.004 in)
0.10 mm (0.004 in)
CYLINDER/PISTON
90°
PISTON
6.5 mm (0.26 in)
PISTON PIN
PISTON RING
9-7