Piston Clearance; Combination Of Piston And Cylinder - Yamaha YZ250(R)/LC Owner's Service Manual

CYLINDER HEAD, CYLINDER AND PISTON
EC474602

Piston clearance

1. Calculate:
9 Piston clearance
Out of limit ¡ Replace piston, and piston
ring and/or cylinder.
Refer to "Cylinder" and "Piston".
PISTON
CLEARANCE
Piston clearance:
Standard
0.045~0.050 mm
(0.0018~0.0020 in)
EC474700

Combination of piston and cylinder

1. Check:
9 Cylinder mark a
Cylinder mark a a
A
B
C
D
2. Check:
9 Piston mark a
Piston mark a a (color)
A (red)
B (orange)
C (green)
D (purple)
4-25
ENG
CYLINDER PISTON
=
–
BORE DIAMETER
<Limit>
0.1 mm
(0.004 in)
Cylinder size
66.400~66.402 mm
(2.61417~2.61425 in)
66.404~66.406 mm
(2.61433~2.61441 in)
66.408~66.410 mm
(2.61449~2.61457 in)
66.412~66.414 mm
(2.61465~2.61472 in)
Piston size
66.352~66.355 mm
(2.61228~2.61240 in)
66.356~66.359 mm
(2.61244~2.61256 in)
66.360~66.363 mm
(2.61260~2.61272 in)
66.364~66.367 mm
(2.61276~2.61287 in)