Yamaha TT-R125EY, Руководство по обслуживанию

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4-36
ENG
CYLINDER AND PISTON
2. Position:
• Piston ring
(in cylinder)
Insert a ring into the cylinder and push it
approximately 40 mm (1.57 in) into the cylinder.
Push the ring with the piston crown so that the
ring will be at a right angle to the cylinder bore.
a
40 mm (1.57 in)
3. Measure:
• Ring end gap
Out of specification
→
Replace.
You cannot measure the end gap on the
expander spacer of the oil control ring. If the oil
control ring rails show excessive gap, replace
all three rings.
Piston ring
1. Measure:
• Ring side clearance
Use a feeler gauge.
Out of specification
→
Replace the piston
and rings as a set.
Clean carbon from the piston ring grooves and
rings before measuring the side clearance.
Side clearance:
Standard <Limit>
Top 0.035 ~ 0.090 mm 0.12 mm
Ring (0.0014 ~ 0.0035 in) (0.0047 in)
2nd 0.020 ~ 0.060 mm 0.12 mm
Ring (0.0008 ~ 0.0024 in) (0.0047 in)
End gap:
Standard <Limit>
Top 0.15 ~ 0.30 mm 0.4 mm
Ring (0.006 ~ 0.012 in) (0.016 in)
2nd 0.15 ~ 030. mm 0.4 mm
Ring (0.012 ~ 0.018 in) (0.016 in)
Oil ring 0.20 ~ 0.70 mm _
(0.01 ~ 0.03 in)
TIP
TIP
TIP