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1. Spark plug wrench

To check the spark plug

1.Check that the porcelain insulator around the center electrode of the spark plug is a medi- um-to-light tan (the ideal color when the ATV is ridden normally).

NOTE:

If the spark plug shows a distinctly different color, the engine could be defective. Do not attempt to diagnose such problems yourself. Instead, have a Yamaha dealer check the ATV.

2.Check the spark plug for electrode erosion and excessive carbon or other deposits, and

replace it if necessary.

Specified spark plug:

NGK/CR7HSA

To install the spark plug

1.Measure the spark plug gap with a wire thick- ness gauge and, if necessary, adjust the gap to specification.

Spark plug gap:

0.6–0.7 mm (0.024–0.028 in)

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1.Spark plug gap

2.Clean the surface of the spark plug gasket

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