PERIODIC MAINTENANCE AND ADJUSTMENT
7-9
7
4. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit.
To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).
TIP
_
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.
_
2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.
To install the spark plug
1. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
2. Clean the surface of the spark
plug gasket and its mating sur-
face, and then wipe off any grime
from the spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
TIP
_
If a torque wrench is not available when
installing a spark plug, a good estimate
of the correct torque is 1/4–1/2 turn
past finger tight. However, the spark
plug should be tightened to the speci-
fied torque as soon as possible.
_
4. Install the spark plug cap.
5. Install the panel.
1. Spark plug wrench
ZAUU0579
Specified spark plug:
C6HSA (NGK) or U20FS-U (DENSO)
1. Spark plug gap
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
ZAUU0703
1
Tightening torque:
Spark plug:
15 Nm (1.5 m·kgf, 11 ft·lbf)
20BF8199E2.book Page 9 Monday, February 28, 2011 10:46 AM
