Yamaha DT125RE 2005 Service Manual page 181

INSPECTION AND REPAIR
Cylinder
Bore "C"
Taper "T"
Out of
round "R"
C = maximum of D
T = maximum of D
D or D
5
R = maximum of D
D , D
2 4
b. If out of specification, rebore or replace the
cylinder, and replace the piston and piston
rings as a set.
c. Measure piston skirt diameter "P" with the
micrometer.
Piston size "P"
Standard
Oversize
Oversize
d. If out of specification, replace the piston
and piston rings as a set.
e. Calculate the piston-to-cylinder clearance
with the following formula.
f. If out of specification, rebore or replace the
cylinder, and replace the piston and piston
rings as a set.
EAS00264
CHECKING THE PISTON RINGS
1. Measure:
• piston ring side clearance
Out of specification k a
ton and piston rings as a set.
5-19
Standard
56.00 ~ 56.02 mm
(2.204 ~ 2.205 in)
—
—
~ D
1 2
or D - maximum of
1 2
6
, D or D - minimum of
1 3 5
or D
6
Micrometer
90890 - 03008
56.34 ~ 56.40 mm
(2.218 ~ 2.220 in)
56.65 mm (2.23 in)
56.90 mm (2.24 in)
Piston-to-cylinder clearance =
Cylinder bore "C" -
Piston skirt diameter "P"
Piston-to-cylinder clearance
0.045 ~ 0.050 mm (0.0018 ~
0.0020 in)
Limit: 0.1 mm (0.004 in)
ENG
Limit
0.05 mm
(0.001968 in)
0.01 mm
(0.00039 in)
Replace the pis-