Here is a step-by-step guide on how to adjust the spark plug gap on a 2002 Honda Shadow 1100c:
1. Locate the spark plugs on the left and right side of the engine behind the cylinders.
2. Remove the spark plug caps.
3. Use a spark plug wrench to loosen the spark plugs.
4. Remove the spark plugs.
5. Check the spark plug gap using a feeler gauge. The gap should be between 0.8 - 0.9 mm (0.031 - 0.035 in).
6. If the gap is too small, carefully bend the spark plug electrode away from the center electrode to increase it. If the gap is too large, gently bend the spark plug electrode towards the center electrode to make it smaller.
7. Reinstall the spark plugs and hand-tighten them.
8. Use the spark plug wrench to tighten the spark plugs to 18 ft-lb (25 N-m).
9. Reinstall the spark plug caps and reconnect all electrical wiring.
