Honda VTX1800R Owner's Manual page 114

7. Make sure the plug washer is in good
condition.
8. With the plug washers attached, thread
the spark plugs in by hand to prevent
cross-threading.
(4)
(4) spark plug gap
9. Tighten each spark plug:
If the old plug is good:
1/8 turn after it seats.
If installing a new plug, tighten it
twice to prevent loosening:
a) First, tighten the plug:
NGK: 3/4
DENSO: 1/2
b) Then loosen the plug.
c) Next, tighten the plug again:
1/8 turn after it seats.
Improperly tightened spark plugs can
damage the engine. If a plug is too loose,
a piston may be damaged. If a plug is too
tight, the threads may be damaged.
10. Reinstall the spark plug caps. Take care
to avoid pinching any cables or wires.
Servicing Your Honda
Spark Plugs
turn after it seats.
turn after it seats.
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