low tension coil burn outs

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spannerman
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Hi all,anybody had issues with low tension coils failing in under 100 miles,this is second in a couple of months ,the voltage regulator is not charging battery ,could this be the problem and over loading system
rosscla
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The LT coil is part of the ignition circuit which should be separate from the lighting / battery circuit unless it's been incorrectly wired or you have a short.
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coaster
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The coil is completely separate from the lighting coils except that they might use the same earth tag on the stator (check the rivet is tight). LT coils are notoriously unreliable so yes it is entirely possible that it has failed again. They don't usually 'burn out' though, they usually fail by either going open circuit (broken coil wire) of the insulation breaks down and vibration is the cause. You can reduce the effects of vibration by literally glueing every wire in place with araldite and also smearing the coil with it too. Have you checked the resistance of the coil?
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spannerman
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Maybe saying burnt out is a bit harsh,the tape has stained brown on one side of this one and now reads a resistance of 150 instead of 500 ish,me thinks the varnish has melted causing a short or coil has broken down and yes I know the lighting and ignition are separate except for earths , Thanks for the replies gents I will check the rivets first,
Muppet
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bad earth +1
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oldbiker
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i would be tempted to say thay you have a short circuit at some point after the stator as open circuit and poor conections would be unlikey to cause a coil to overheat.

concider replacing the wires from the stator when you replace the damaged coil.
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