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Author Topic: wierd electrical gremlin  (Read 1669 times)

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Offline cbr-eric

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wierd electrical gremlin
« on: November 12, 2009, 03:41:44 PM »
just in general, what would cause there to be spark when I hold the sparkplug AWAY from the motor a little bit, but when I ground it to the motor I get nothing? bad ground?  not on a 750, but I figure it is just electrical principal and should apply.  thanks guys!
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Offline number13

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Re: wierd electrical gremlin
« Reply #1 on: November 12, 2009, 04:42:20 PM »
Probably just a bad spark plug.
Does a known new plug behave the same?
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Offline Steve F

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Re: wierd electrical gremlin
« Reply #2 on: November 12, 2009, 05:56:05 PM »
Your description leads me to think that the plug center elecrode is shorted to the plug outer.  When you hold the plug away from the engine, I'm assuming that the spark happens between the engine and the plug case?
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Offline cbr-eric

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Re: wierd electrical gremlin
« Reply #3 on: November 12, 2009, 06:29:06 PM »
happens to both plugs (it is a twin) and it goes up through the electrode, and arcs from the armeture.  thanks guys!
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Offline Spanner 1

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Re: wierd electrical gremlin
« Reply #4 on: November 12, 2009, 06:31:07 PM »
Yep, carbon shorted outer to center electrode, for sure.
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Offline cbr-eric

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Re: wierd electrical gremlin
« Reply #5 on: November 14, 2009, 12:38:41 PM »
well I cleaned the plugs up to see if I could get ANY spark from them.  got it all set up, hit the starter and ZAP.  all lights off.  no pwer anywhere.  cdi checks out ok, so does the bsttery and magnetic starter switch.  what the hell, I hate electrical issues and more importantly, this bike lol!  anyone have ANY thoughts?  thanks
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Offline cbr-eric

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Re: wierd electrical gremlin
« Reply #6 on: May 10, 2010, 06:10:44 PM »
long past due, but it was the plugs. changed em out and no more issues (with that part of the bike at least lol!!!)
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