Yamaha 2003 TZR50, Service Manual

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ENG
INSPECTION AND REPAIR
4-17
5. Measure
• Piston free play:
Outside specifications Grind the
cylinder or replace the piston
C: Internal cylinder diameter
P: External piston diameter
PISTON RINGS
1. Measure:
• Lateral clearance
Out of specifications Replace the pis-
ton and/or rings
Use the thickness gauge
2. Install:
• The piston ring (in the slot for the ring)
• Push the ring with the piston crown.
3. Measure:
• Clearance between ends
Out of specifications Change set of
rings.
Use the feeler gauge
PISTON PIN AND BEARING
1. Lubricate:
• The piston pin
• The bearing
2. Install:
• The piston pin
• Bearing (on the little end)
Piston clearance = C- P:
0.049 ~ 0.062 mm
Feeler gauge:
90890 - 03079
Clearance between ends:
Upper ring / 2nd ring
0.15 ~ 0.30 mm
Lateral clearance:
Upper ring / 2nd ring
0.03 ~ 0.06 mm