Yamaha DT125RE 2005 Service Manual page 180

INSPECTION AND REPAIR
a. Place a straightedge
gauge
b. Measure the warpage.
c. If the limit is exceeded, resurface the cylin-
der head as follows.
d. Place a 400 ~ 600 grit wet sandpaper on
the surface plate and resurface the cylinder
head using a figure-eight sanding pattern.
NOTE:
To ensure an even surface, rotate the cylinder
head several times.
EAS00255
CHECKING THE CYLINDER AND PISTON
1. Check:
• piston wall
• cylinder wall
Vertical scratches
cylinder, and replace the piston and piston
rings as a set.
2. Measure:
• piston-to-cylinder clearance
a. Measure cylinder bore "C" with the cylinder
bore gauge.
NOTE:
Measure cylinder bore "C" by taking side-to-
side and front-to-back measurements of the
cylinder. Then, find the average of the measu-
rements.
5-18
ENG
across the cylinder head.
Rebore or replace the
Cylinder bore gauge
56.00 ~ 56.02 mm (2.2047 ~
2.2055 in)
and a thickness