Checking The Piston And Piston Pin - Yamaha KT100SEC Owner's Service Manual

CHECKING THE ENGINE PARTS

CHECKING THE PISTON AND PISTON PIN

1. Inspect:
Piston crown
●
Use a scraper.
Ring groove
●
Use a used piston ring.
Wear/Scratches/Damage → Replace.
2. Measure:
Piston diameter
●
Micrometer
10 mm (0.39 in) from the piston bottom
edge.
Standard piston diameter
51.970∼51.990mm
3. Check:
Free play (When the piston pin
●
in the piston
There should be no noticeable for the play.
Free play exists → Replace piston pin and/or
piston.
4. Inspect:
Check the free play when the piston pin
●
bearing are in place in the connecting rod.
Free play exists → Replace piston pin and/or
small end bearing.
CHECKING THE PISTON RING
1. Measure:
End gap
●
Thickness gauge
Insert a ring into the cylinder and push it
approximately 10 mm (0.39 in) into the cylinder.
End gap limit
0.5mm
Out of specification → Replace
4-11
ENG
carbon deposits
carbon deposits
is in place
.)
and