Yamaha TTR90(M), Руководство по эксплуатации для владельца

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ENG
CYLINDER AND PISTON
REMOVAL POINTS
Piston
1. Remove:
●
Piston pin clips 1
●
Piston pin 2
●
Piston 3
NOTE:
Before removing the piston pin clip, cover the
crankcase opening with a clean towel or rag to
prevent the clip from falling into the crankcase
cavity.
Piston ring
1. Remove:
●
Piston rings
NOTE:
Spread the end gaps apart while at the same
time lifting the piston ring over the top of the
piston crown, as shown in the illustration.
INSPECTION
Cylinder and piston
1. Inspect:
●
Cylinder and piston walls
Vertical scratches
→
Replace cylinder
and piston.
2. Measure:
●
Piston-to-cylinder clearance
Measurement steps:
1st step:
●
Measure the cylinder bore “C” with a cylin-
der bore gauge.
Cylinder bore “C”
47.000 ~ 47.005 mm
(1.8504 ~ 1.8506 in)
Taper limit “T” 0.05 mm (0.002 in)
Out of round “R” 0.05 mm (0.002 in)
NOTE:
Measure the cylinder bore “C” in parallel to
and at right angles to the crankshaft. Then,
find the average of the measurements.