Honda CRF125F 2021 Owner's Manual page 81

SPARK PLUG
Refer to the Safety Precautions on page 55.
Recommended plug:
Standard:
CPR6EA-9 (NGK)
For most riding conditions this spark plug
heat range number is satisfactory.
Never use a spark plug with an improper
heat range. Severe engine damage could
result.
1. Disconnect the spark plug cap.
2. Clean any dirt from around the spark
plug base.
3. Remove the spark plug using a spark
plug wrench provided in the tool kit.
4. Visually inspect the spark plug
electrodes for wear. The centre
electrode should have square edges and
the side electrode should not be eroded.
5. Discard the spark plug if there is
apparent wear or if the insulator is
cracked or chipped.
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