The tools I used:
- ratchet with 18mm spark plug socket or a 18mm deep socket (the original wrench was lost by the previous owner)
- spark plug gap tool
- anti-seize lubricant (optional)
- dielectric grease (optional)
- 2 x NGK DPR8EA-9 spark plugs
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1) Put the motorcycle on the center stand to make it more stable
2) Carefully pull the spark plug boot off of the top of the plug.
Boot removed and spark plug exposed:
3) Then use compressed air or a rag to clean around the base of the spark plug.
4) Using an 18mm deep socket or spark plug wrench, remove the spark plug
The old (left) vs. the new (right). The gap on the old is over 0.9mm and out of spec. The electrode also appears a bit worn.
5) Check the electrode gap on the new NGK DPR8EA-9. It should be between 0.8-0.9mm.
6) I added a very small amount of anti-seize lubricant on the threads of the spark plug to make it easier to remove in the future.
7) Hand tighten the plug and then use the wrench another 1/4-1/2 turn. The engine is made of aluminum and it could easily damage by over tightening.
8) I used a small amount of dielectric grease on the end of the spark plug to prevent corrosion.
9) Attach the spark plug boot and ensure it fits snuggly.
10) Repeat on the other side.
11) Go for a ride!
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