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CVO Technical => General CVO discussion => Topic started by: +RO@D*R@GE+ on May 28, 2016, 12:59:32 AM

Title: spark plugs with black on top
Post by: +RO@D*R@GE+ on May 28, 2016, 12:59:32 AM

so changed my spark plugs and the tach started jumping around at idle. when I pulled the wires off the front spark plug had black on the top. Cleaned it off and ran good. checked it a couple more times finding black on it again but less and less each time till nothing. are my plugs arcing? do I need to change them? what could the black be? https://goo.gl/photos/nbx9MyejhAGGUuoK7[/url (https://goo.gl/photos/nbx9MyejhAGGUuoK7)

Title: Re: spark plugs with black on top
Post by: kojak on May 28, 2016, 07:52:38 AM

I'm guessing the plug boot is wearing out. Replace the spark plug wires and see if it fixes your issue.

Title: Re: spark plugs with black on top
Post by: grc on May 28, 2016, 08:17:57 AM

Use a small light and inspect the inside of the boots, take a clean thin rag and run it around in the boot and see what it picks up.  The most likely source of the black is the boot material, and if it's breaking down (unusual for a four year old bike), replace the boots or the entire wires.  Stick with the stock wires and resist the temptation to go with aftermarket "performance" wires.

Btw, I've always put a thin coating of dielectric compound on the inner wall of my plug wire boots.  It makes installation and removal easier, and keeps the rubber from sticking to the plug.

Jerry