Yamaha BLASTER YFS200N - Manual (Page 107)

8-7
h. Check the oil level.
EBU00286
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 machine 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.
Before installing the spark plug, measure the
electrode gap with a feeler gauge and adjust to
specification.
Standard spark plug:
BR8ES (NGK)
Spark plug gap:
0.7 ~ 0.8 mm (0.028 ~ 0.031 in)