Piston, Piston Ring, And Piston Pin - Yamaha XC125 Service Manual

PISTON, PISTON RING, AND PISTON PIN
Piston
1. Inspect:
s.ornrn e Piston wall
(0.2in) Wear/Scratches/Damage -_ Replace.
2. Measure:
o Piston outside diameter "P"
Use a Micrometer.
Out of specification -_ Replace.
NOTE:
Measurement should be made at a point 5.0 mm
(0.2 in) above the bottom edge of the piston.
Piston Outside Diameter "P"
48.945 _ 48.985 mm
Standard
-- (1.927 ~ 1.929 in)
Oversize 2 49.50 (1.949 in)
mm
Oversize 4 50.00 mm (1.969 in)
3. Measure:
• Piston clearance
Out of specification -, Rebore cylinder
or replace piston.
_ 0.0016 in) nee = C -- P: 1
,040 mm |
C: Cylinder bore P: Piston outside diameter
; O -'_'_ Piston Ring
_____ _ ) 1. Measure:
® Side clearance
Use a Feeler Gauge (_.
Out of specification -* Replace piston
j and/or rings.
0.03 ~ 0.07 rnm
_ Side Top (0.0012 ~ 0.0028 in)
'_ _"" G_//_ Clearance 2nd 0.02 _ 0.06 mm
...... (0.0008~0.0024 in)
, -- _ _ Limit: 0.12 mm (0.0047 in)
• ,. .-
......... (_ Pistonring (taper)
.............. (_ Piston ring (barrel)
_: _) Piston
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