Spark Plug Inspection - Yamaha RAPTOR YFM80RT Owner's Manual

EBU11820

Spark plug inspection

The spark plug is an important engine compo-
nent and is easy to inspect. The condition of the
spark plug can indicate the condition of the
engine.
For example, a very white center electrode
porcelain color could indicate an intake air leak
or carburetion problem for that cylinder. Do not
attempt to diagnose such problems yourself.
Instead, take the ATV to a Yamaha dealer. You
should periodically remove and inspect the
spark plug because heat and deposits will cause
the spark plug to slowly break down and erode.
If electrode erosion becomes excessive, you
should replace the spark plug with one of the
proper type.
Standard spark plug:
CR7HS (NGK)
Before installing the spark plug, measure the
electrode gap with a wire thickness gauge and
adjust it to specification.
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
a
a. Spark plug gap
8-9