Yamaha 2003 yz85, Owner'S Service Manual

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ENG
Piston ring
1. Install:
●
Piston ring
Into the cylinder.
Push the ring with the piston crown.
2. Measure:
●
End gap
Use a thickness gauge
1
.
Out of limit
→
Replace.
Ring end gap (installed):
0.30 ~ 0.45 mm
(0.012 ~ 0.018 in)
<Limit>: 0.80 mm (0.031 in)
5PA40570
3. Measure:
●
Side clearance
Use a thickness gauge
1
.
Out of limit
→
Replace piston and/or ring.
NOTE:
Check at several points.
Side clearance:
0.030 ~ 0.065 mm
(0.001 ~ 0.003 in)
<Limit>: 0.1 mm (0.004 in)
5PA40580
5PA40590
Piston clearance
1. Calculate:
●
Piston clearance
Out of limit
→
Replace piston, and piston
ring and/or cylinder.
Refer to “Cylinder” and “Piston”.
PISTON
CLEARANCE
=
CYLINDER
BORE
–
PISTON
DIAMETER
CYLINDER HEAD, CYLINDER AND PISTON