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Discussion Starter · #1 ·
I just noticed that the black wires coming off the backside of the coils are getting hot and smoking. I removed the gas tank and seat and found that they got so hot that they started to melt through the insulation of some of the other wires they were clustered with. The bike runs great and i've had no issues with starting, idle, etc. any ideas or suggestions before my bike has a catastrophic meltdown? I don't have a clue what would cause this.
 

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Very odd indeed. A bad coil (shorted turns) could cause that but the chances of both going bad at the same time would be extremely rare.



It is possible that the CDI has leakage in both of the high voltage caps but then it probably wouldn't run worth a darn if at all.



With the engine not running but the key on measure the input voltage at the coils.

In theory, with a CDI bike there shouldn't be any voltage present.



The way a CDI system works is there's nothing on the coils, when it's ready to fire it pulses several hundred volts through the coil primary but only for a few milliseconds.
 

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Did you ever figure out what was causing this problem?
 

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Discussion Starter · #6 ·
Did you ever figure out what was causing this problem?
I think I was mistaking smoke from something else for the wires. I haven't had any issues with it since this time. It could be that the wires were in fact smoking from a short and my separating them, routing and taping them up better fixed the issue, but I think the smoke might have been coming from the drain tube filter I have installed. It's all in the same area on my bike and when I seen the melted wire insulation I assumed it was the wires getting hot and smoking. But the wires were also in the same vicinity as a couple of tig welds that were planted from way back when on the seat mount in the back so that would explain the melted insulation. In any event no more smoke and the wires do not get hot to the touch anywhere that I can tell. Thanks for asking, I probably should have given an update to this anyways.
 

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My car has done that twice and it pisses me off to no end when I can't locat where the smoke came from, can't see any obvious damage yet it runs just fine afterwards.
 

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Thanks for the update,,I wondered if it may have been something other than the coil wires being hot.
 
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