Honda NX500 Owner's Manual page 63

3. Visually inspect the spark plug
electrodes for wear. The center elec-
trode should have square edges and the
side electrode should not be eroded .
Discard the spark plug if there is
apparent wear or if the insulator is
cracked or chipped.
4. Check the spark plug gap ( 1) using a
wire-type feeler gauge. If adjustment is
necessary, bend the side electrode (2)
carefully.
The gap should be:
0.80-0.90
mm
(0.031-0.035
in)
Make sure the plug washer is in good
condition .
5. With the plug washer attached, thread
the spark plug in by hand to prevent
cross-threading.
56
6. Tighten a new spark plug 1/2 turn with
a spark plug wrench to compress the
washer.
If
you are reusing a plug, it
should only take 1/8-1/4 turn after the
plug seats.
CAUTION:
*
The spark plug must be securely
tightened. An improperly tight-
ened plug can become very hot
and possibly damage the engine.
*
Never use a spark plug with an im-
proper heat range. Severe engine
damage could result.