Yamaha XT1200Z(Z) 2010, Service Manual

Page: 335 / 616

CYLINDER AND PISTONS
5-40
3. Measure:
• Piston ring end gap
Out of specification
→
Replace the piston
ring.
TIP
The oil ring expander spacer’s end gap cannot
be measured. If the oil ring rail’s gap is exces-
sive, replace all three piston rings.
EAS24440
CHECKING THE PISTON PINS
The following procedure applies to both of the
piston pins.
1. Check:
• Piston pin
Blue discoloration/grooves
→
Replace the
piston pin and then check the lubrication sys-
tem.
2. Measure:
• Piston pin outside diameter “a”
Out of specification
→
Replace the piston pin.
3. Measure:
• Piston pin bore diameter “b”
Out of specification
→
Replace the piston.
4. Calculate:
• Piston-pin-to-piston-pin-bore clearance
Out of specification
→
Replace the piston pin
and piston as a set.
EAS24470
INSTALLING THE PISTONS AND CYLINDER
The following procedure applies to both of the
pistons.
a. 40.0 mm (1.57 in)
Piston ring
Top ring
End gap (installed)
0.20–0.35 mm (0.0079–0.0138
in)
2nd ring
Limit
0.60 mm (0.0236 in)
End gap (installed)
0.35–0.50 mm (0.0138–0.0197
in)
Limit
0.85 mm (0.0335 in)
Oil ring
End gap (installed)
0.20–0.70 mm (0.0079–0.0276
in)
Piston pin outside diameter
21.991–22.000 mm (0.8658–
0.8661 in)
Limit
21.971 mm (0.8650 in)
Piston pin bore inside diameter
22.004–22.015 mm (0.8663–
0.8667 in)
Limit
22.045 mm (0.8679 in)
• Piston-pin-to-piston-pin-bore clearance =
Piston pin bore inside diameter “b” -
Piston pin outside diameter “a”
Piston-pin-to-piston-pin-bore
clearance
0.004–0.024 mm (0.00016–
0.00094 in)