Yamaha 2004 TT600RE, Service Manual

Page: 236 / 382

INSPECTION AND REPAIR
5-32
ENG
PISTON RINGS
1. Measure:
•
Side clearance of rings
Use a thickness gauge.
Out of specification
➔
Replace piston.
NOTE:
Before measuring side clearance, remove carbon
deposits from the piston ring seats and from the
rings themselves.
Piston ring side clearance
(installed):
Upper ring 0.04 ~ 0.08 mm
Lower ring 0.03 ~ 0.07 mm
<Limit>: 0.13 mm
Oil scraper 0.02 ~ 0.06 mm
Piston ring end gap
(fitted into cylinder):
Upper ring
0.30 ~ 0.45 mm
<Limit>: 0.7 mm
Lower ring
0.30 ~ 0.45 mm
<Limit>: 0.8 mm
Oil scraper (tracks) 0.20 ~ 0.70 mm
2. Install:
•
Ring (into the cylinder)
NOTE:
Fit each ring into the cylinder and push it to about
20 mm from the top edge of the cylinder. Push the
ring into the cylinder with the piston so that it is
perfectly perpendicular to the cylinder axis.
(a) 20 mm
3. Measure:
•
Ring end gap
Out of specification
➔
Replace.
NOTE:
It is impossible to measure the oil scraper end
gap. If the oil scraper port appears too large,
replace all three rings.