Honda CRF250RL 2017 Owner's Manual page 62

Spark Plug Checking Spark Plug
u
Tighten the spark plug:
8.
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:
1/2 turn after it seats.
b) Then loosen the plug.
c) Next, tighten the plug again:
1/8 turn after it seats.
NOTICE
An improperly tightened spark plug 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.
Reinstall the spark plug cap. Take care to
9.
avoid pinching any cables or wires.
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