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Ignition Coil Overheating?

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Old Apr 4, 2011 | 03:52 PM
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Default Ignition Coil Overheating?

Lately my bike has been cutting out when I go 80+ for long periods of time. I don't loose electricity to the rest of the bike and a few seconds later it'll start back up if I let off the throttle.

To me this sounds like my coil is getting hot, pulling too much amperage, and tripping the power relay I wired up when I installed my Twin Tec ignition module and coil.

I don't know if it is related but I have also dropped in fuel economy this past week for 50 to 45 mpg. Any thoughts?

EDIT: This is a 98 XL1200 conversion.
 
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Old Apr 4, 2011 | 04:23 PM
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I had a similar problem. It turned out that the electric wires going to the coil were wiggling loose. Not the plug wires but the small electric wires. The connections were too loose. The wire would just slide off the post on the coil. I just crimped it and now it holds fine
 
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Old Apr 4, 2011 | 08:01 PM
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When you say "Tripping the relay", what do you mean? If you have their power relay kit, there is no type of overload trip or anything with that. If in fact your relay is shutting off and preventing power from getting to the coil, you need to check all connections in the wiring.
 
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Old Apr 4, 2011 | 10:40 PM
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I didn't buy their's. I just wired my own. I haven't confirmed if this is an overload condition, it just seems like it to me. Just putting some feelers out there to see if anyone else has ran into this.
 
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Old Apr 4, 2011 | 10:49 PM
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Sounds like a bad module. Why the power relay? The twin tecs are plug and play.
 
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Old Apr 4, 2011 | 11:50 PM
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Oh don't say bad module. I just replaced it a few months ago. I added the power relay because I needed it. The starter was pulling too many amps and the coil didn't get enough to start the engine.
 
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Old Apr 5, 2011 | 06:28 AM
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Weird.
I just installed a twin tec on my 99 with no problems at all. No power relay.

The twin tec stores all its info on its computer. Have you plugged it in and checked it out yet? Have you followed the troubleshooting guide that came with the module?

Did you switch to single a single fire coil along with the module or is it a stock coil? There is a certain resistance the coil has to be. You may just need a new coil.
 
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Old Apr 5, 2011 | 08:51 AM
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I switched to the single fire coil when I replaced the module. I haven't hooked my computer to it. I don't have the cable. I looked at the troubleshooting tree but it didn't show intermittent problems.
 
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Old Apr 5, 2011 | 09:17 AM
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I don't understand how the relay would give full battery voltage when the starter is running. If the starter draws the battery voltage down to 10v while it is running, then everything on the bike will be getting 10v no matter how it is wired up.
 
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Old Apr 5, 2011 | 10:03 AM
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The coil may not need full source voltage to create spark. I don't know since I don't have their specs on it in front of me. I just know when I didn't have the power relay between the coil and starter, too much amperage was being drawn for the original bike harness to handle. The starter wouldn't spin fast enough to start the engine.

On their site it says that some high compression engines have a problem with this.
 
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