Yamaha TT-R125(R) 2002, Owner'S Service Manual

Page: 172 / 510

3 - 11
INSP
ADJ
VALVE CLEARANCE INSPECTION AND ADJUSTMENT
VALVE CLEARANCE INSPECTION AND
ADJUSTMENT
NOTE:
●
The valve clearance should be adjusted
when the engine is cool to the touch.
●
The piston must be at Top Dead Center
(T.D.C.) on compression stroke to check or
adjust the valve clearance.
1. Remove:
●
Seat
●
Fuel tank
Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section in the CHAPTER 4.
Adjustment steps:
●
Adjust the pilot air screw.
Refer to “PILOT AIR SCREW ADJUST-
MENT” section.
●
Turn the throttle stop screw 1 until the
specified engine idling speed.
To increase idling speed
→
Turn the throttle stop screw 1 in
a
.
To decrease idling speed
→
Turn the throttle stop screw 1 out
b
.
Inductive tachometer:
YU-8036-B/90890-03113
Engine idling speed:
1,300 ~ 1,500 r/min
2. Remove:
●
Spark plug
●
Intake tappet cover
1
●
Exhaust tappet cover
2
●
O-ring
3. Remove:
●
Timing mark accessing screw 1
●
Crankshaft end accessing screw 2
●
O-ring