Honda Metropolitan CHF50 Service Manual page 63

MAINTENANCE
Check the insulator for cracks or damage, and the
electrodes for wear, fouling or discoloration.
Replace the plug if necessary.
If the electrode is contaminated with carbon depos-
its, clean the electrode using a spark plug cleaner.
Replace the plug if necessary.
Always use the specified spark plug on this scooter.
SPEDIFIED SPARK PLUG:
Standard:
CR8EH-9 (NGK), U24FER9 (DENSO)
For cold climate (below 5°C/41 °F):
CR7EH-9 (NGK), U22FER9 (DENSO)
For extended high speed riding:
CR9EH-9 (NGK), U27FER9 (DENSO)
Measure the spark plug gap between the center and
side electrodes with a wire type feeler gauge.
If necessary, adjust the gap by bending the side
electrode carefully.
SPARK PLUG GAP: 0.80 - 0.90 mm (0.031 - 0.035 in)
CENTER ELECTRODE
INSULATOR
SIDE ELECTRODE
Install the spark plug in the cylinder head and hand SPARK PLUG
tighten, then torque to specification.
TORQUE: 12 N m (1.2 kgf-m, 9 Ibfft)
Install the spark plug cap.
Install the plug maintenance lid.
Close the fuel tank cap lid.
0.80 - 0.90 mm (0.031 - 0.035 in)
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