Yamaha YZ250F(W), Руководство по эксплуатации для владельца

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ENG
CYLINDER AND PISTON
Cylinder bore “C”
77.00 ~ 77.01 mm
(3.0315 ~ 3.0319 in)
Taper limit “T” 0.05 mm (0.002 in)
Out of round “R” 0.05 mm (0.002 in)
“C” = Maximum D
“T” = (Maximum D
1
or D
2
)
– (Maximum D
5
or D
6
)
“R” = (Maximum D
1
, D
3
or D
5
)
– (Minimum D
2
, D
4
or D
6
)
• If out of specification, replace the cylinder,
and replace the piston and piston rings as
set.
2nd step:
• Measure the piston skirt diameter “P” with
a micrometer.
a
8 mm (0.31 in) from the piston bottom edge
Piston size “P”
Standard
76.955 ~ 76.970 mm
(3.0297 ~ 3.0303 in)
• If out of specification, replace the piston
and piston rings as a set.
3rd step:
• Calculate the piston-to-cylinder clearance
with following formula:
Piston-to-cylinder clearance =
Cylinder bore “C” –
Piston skirt diameter “P”
Piston-to-cylinder clearance:
0.030 ~ 0.055 mm
(0.0012 ~ 0.0022 in)
<Limit>: 0.1 mm (0.004 in)
• If out of specification, replace the cylinder,
and replace the piston and piston rings as
set.