Honda FF 300 Owner's Manual page 42

Spark plug service
Recommended spark plug:
Never use a spark plug with an improper heat range.
To ensure proper engine operation, the spark plug must be properly
gapped and free of deposits.
1. Pull off the spark plug inspection lid and disconnect the spark plug
cap.
2. Remove the spark plug with spark plug wrench.
If the engine has been running, the muffler will be very hot. Be
careful not to touch the muffler.
SPARK PLUG CAP
INSPECTION LID
3. Visually inspect the spark plug. Discard
it if the insulator is cracked or chipped.
Clean the spark plug with a wire brush if
it is to reused.
4. Measure the plug gap with a feeler
gauge.
Spark plug gap:
−
0.6 0.7 mm (0.024 0.028 in)
Correct as necessary by bending the
side electrode.
CR4HSB (NGK)
−
, U14FSR-UB (DENSO)
SPARK PLUG WRENCH
SIDE ELECTRODE
0.6 0.7 mm −
(0.024 0.028 in) −
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