Spark plugs

kwallace21

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Hello all. While I was in mechanic mode changing my Fd oil I decided to change my spark plugs. All plugs were perfect colour apart from one which was a little darker especially around the threads. It was the same last time I changed plugs. Pretty certain it was left hand pot, lower secondary plug. Oil gathering while it occasionally sits on side stand perhaps?
 
Oil running into the cylinder will throw out blue smoke when you start the engine. But unless there are gallons of the stuff it should still have no effects on spark plug colour..

The secondary plugs fire after the primaries when there should be no fuel to burn. Try swapping the primary coils left/right and use the bike for a while. If the dark secondary plug moves to the other side you might have a primary coil problem.
 


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