8-19
8
EBU24000Adjusting the engine idling speed The engine idling speed must be checked and, if
necessary, adjusted as follows at the intervals
specified in the periodic maintenance and lubrica-
tion chart.TIPA diagnostic tachometer is needed to make thisadjustment.
1. Start the engine and warm it up.TIPThe engine is warm when it quickly responds to thethrottle.
2. Attach the tachometer to the spark plug lead.
3. Check the engine idling speed and, if neces-
sary, adjust it to specification by turning the
throttle stop screw at the carburetor. To in-
crease the engine idling speed, turn the throt-
tle stop screw in direction (a), and to decrease
it, turn the screw in direction (b).
TIPIf the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make theadjustment.1. Throttle stop screwEngine idling speed:
1500–1600 r/min
1
(a)
(b)
U33B70E0.book Page 19 Wednesday, June 11, 2008 1:38 PM
8-31
8 7. Check that the clearance between the speed
sensor and the speed sensor rotor is 3–5 mm
(0.12–0.19 in). If the clearance is out of spec-
ification, adjust the speed sensor position as
follows.
TIPThis specified clearance is necessary for thespeedometer to indicate an accurate reading.
8. Loosen the speed sensor bracket bolt.9. Adjust the position of the speed sensor so that
the clearance between the sensor and the
speed sensor rotor is 3–5 mm (0.12–0.19 in).
10. Tighten the bolt to the specified torque.
EBU24880Lubricating the drive chain The drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
and lubrication chart, otherwise it will quickly wear
out, especially when riding in dusty or wet areas.
Service the drive chain as follows.
1. Speed sensor rotor
2. Speed sensor
3. Speed sensor bracket bolt
4. Clearance
3 2
4
1
Tightening torque:
Speed sensor bracket bolt:
13 Nm (1.3 m·kgf, 9.4 ft·lbf)
U33B70E0.book Page 31 Wednesday, June 11, 2008 1:38 PM
