Yamaha F15A - Cylinder Inspection; Piston Inspection; Service Points

E
CRANKCASE AND CRANKSHAFT
POWR
D
D
1
2
D
D and D
1
2
D and D
3
4
D and D
5
6
70 mm (2.8 in)
40 mm (1.6 in)
10 mm (0.4 in)
a
d
SERVICE POINTS
Cylinder inspection
1. Measure:
9 Cylinder bore
Out of specification → Rebore or
replace the cylinder.
NOTE:
Measure the cylinder bore in parallel and
at a right angle to the crankshaft. Then,
average the measurements.
Piston inspection
1. Measure:
9 Piston diameter
Out of specification → Replace the
piston.
5-38
Standard Wear limit
Cylinder 59.00 ~ 59.02 mm
59.10 mm
bore ”D“ (2.323 ~ 2.324 in) (2.327 in)
Taper 0.08 mm
limit ”T“ — (0.003 in)
Out of 0.05 mm
round limit — (0.002 in)
D = Maximum Dia. (D
1
~D
6
)
T = (maximum D
1
or D
2
) ~ (minimum D
5
or D
6
)
Distance
Piston diameter d
a
5 mm 58.950 ~ 58.965 mm
Standard
(0.20 in) (2.3206 ~ 2.3215 in)
Oversize piston diameter:
*Oversize 1 : 59.25 mm (2.333 in)
Oversize 2 : 59.50 mm (2.343 in)
Pistonpin boss inside diameter:
14.004 ~ 14.015 mm
(0.5513 ~0.5518 in)
*Except for USA
2. Measure:
9 Piston pin boss inside diameter
Out of specification → Replace.