Yamaha XV16AL Service Manual page 274

5
CYLINDERS AND PISTONS
2. Measure:
• piston-to-cylinder clearance
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a. Measure cylinder bore "C" with the cyl-
inder bore gauge.
NOTE:
Measure cylinder bore "C" by taking side-
to-side and front-to-back measurements of
the cylinder. Then, find the average of the
measurements.
Cylinder bore gauge
YU-03017
Cylinder bore "C"
Maximum taper "T" 0.05 mm (0.0016 in)
Out of round "R"
"C" = maximum of D
"T" = maximum of D
D or D
5 6
"R" = maximum of D
– minimum of D
b. If out of specification, replace the cylin-
der, and the piston and piston rings as a
set.
c. Measure piston skirt diameter "P" with
the micrometer.
Micrometer
YU-03009
a 5 mm (0.20 in) from the bottom edge of the
piston
Standard
d. If out of specification, replace the piston
and piston rings as a set.
e. Calculate the piston-to-cylinder clear-
ance with the following formula.
Piston-to-cylinder clearance =
Cylinder bore "C" –
Piston skirt diameter "P"
5 - 55
ENG
95.000 ~ 95.010 mm
(3.7402 ~ 3.7406 in)
0.05 mm (0.0016 in)
~ D
1 6
or D – maximum of
1 2
, D or D
1 3 5
, D or D
2 4 6
Piston size "P"
94.960 ~ 94.975 mm
(3.7386 ~ 3.7392 in)