Yamaha SXV70SJ Supplementary Service Manual page 281

CYLINDER HEAD AND CYLINDER
10. Install:
•
NOTE:
Insert the ring into the cylinder, and push it approxi-
mately 20 mm (0.8 in) into the cylinder. Push in the
ring with the piston crown so that the ring is at right
SCH5210
angles to the cylinder bore.
11. Measure:
•
SCH5220
a
20 mm (0.8 in)
12. Measure:
•
SCH5230
13. Measure:
•
Piston pin-to-piston clearance =
Bore size (piston pin) b –
Outside diameter (piston pin) a
SCH5240
5-12
ENG
Piston ring
(into the cylinder)
Push in the ring with the piston crown.
End gap (piston rings)
Use the thickness gauge 1.
Out of specification → Replace the rings as a
set.
End gap (top):
0.35 ~ 0.55 mm
(0.014 ~ 0.022 in)
End gap (2nd):
0.35 ~ 0.55 mm
(0.014 ~ 0.022 in)
Outside diameter (piston pin) a
Out of specification → Replace the piston pin.
Outside diameter (piston pin) a:
19.995 ~ 20.000 mm
(0.7872 ~ 0.7874 in)
Piston pin-to-piston clearance
Out of specification → Replace the piston.
Piston pin-to-piston clearance =
0.009 ~ 0.015 mm
(0.000354 ~ 0.000591 in)