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2. Install panel E.
EBU29440
Checking the spark plug
The spark plug is an important engine component,
which should be checked periodically, preferably
by a Yamaha dealer. Since heat and deposits will
cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
The porcelain insulator around the center elec-
trode of the spark plug should be a medium-to-light
tan (the ideal color when the vehicle is ridden nor-
mally). If the spark plug shows a distinctly different
color, the engine could be operating improperly.
Do not attempt to diagnose such problems your-
self. Instead, have a Yamaha dealer check the ve-
hicle.
If a spark plug shows signs of electrode erosion
and excessive carbon or other deposits, it should
be replaced.
Before installing a spark plug, the spark plug gap
should be measured with a wire thickness gauge
and, if necessary, adjusted to specification.
Clean the surface of the spark plug gasket and its
mating surface, and then wipe off any grime from
the spark plug threads.
Specified spark plug:
NGK/CR8E
1. Spark plug gap
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Tightening torque:
Spark plug:
12.5 Nm (1.3 m·kgf, 9.4 ft·lbf)
