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By Enelectrax
...... Hello, this is the latest.

I will get another plug cap an NGK one, but for the moment a spark has now decided to appear from doing nothing to it apart from a good looking at and this is with the new coil fitted on, so decided to just change the spark cap over to the old one kind hoping it didn't work so to identify the problem, annoyingly that decided to produce a spark, so it would start now Im sure once the tank goes on, trouble is this could let me down again, any ideas, just makes no sense and could easily dump me at random in the middle of know where again.

Pic is of some samosas I made, as tiring of the bikes behaviour.
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By bbrap
Okay, lets have a think. When it runs, it runs OK until in the middle of nowhere it cuts out with no spark. That implies something is breaking down when it gets hot, that something sometimes comes back to life but not always once cooled. So what have we got? Starting from the head we have a plug, a plug cap, an HT lead and a coil (maybe points and condenser). As you have changed the coil we can (but not definitely) rule that out (I've had a supposedly new coil exhibit strange habits when hot). The HT lead can also not be ruled out, given that when you remove the plug cap the lead also gets a bit of a wiggle which may restore the spark. The plug cap would be my number 1 suspect.

So if I were in your position I would change the plug, cap, and HT lead. Then if that does not stop it I would change the condenser (assuming it has one). Lastly but probably worth looking at the LT side (i.e. when there is no spark are you getting12v at the coil?)

By Enelectrax
Thanks for your thoughts on this Bbrap, yes could well be the lead and cap, I did give it a tighten the other night when stranded but it didn't resolve the problem, and today while the engine is stone cold the spark has been non existant then appeared from touching nothing. Its definately an odd one, I will just have to keep trying to work it out, need to find something concise that is causing this, even though at this moment there is a spark which is good, I could go out there later and there isn't one. Been relayed back twice now by the AA in a short space of time, starting to get stupid as I go out making a racket and it all making sense then arrive back like Billy smarts circus arriving in town.

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By Daiwiskers
H.T. lead connection either at coil or plug cap (Cut a quarter inch off each end and retry )
Still sounds like coil or condenser (if fitted)(if not could be electronic ignition playing up) too me but I an no expert on Enfield's there again I have been turning spanners for 50+ years

What's battery voltage just out of interest?
Cheer's Dai
By bbrap
Given what you have said about not touching anything, can I assume that you have stopped the bike (when it has spark) using either the key or the cut off. Then come back later and no spark (after having turned the key and put the cut off to the run position). In that situation I would 1st check for 12v at the coil when you have no spark as it points to a lack of 12v getting through. Could be a dodgy kill switch or ignition switch reacting to vibration rather than a heat issue (or even a wiring issue caused by turning the bars to a particular position). Should be an easy test if you have a voltmeter and can recreate the no spark situation. At least then you will know if LT or HT is the culprit.
By Daiwiskers
Good call kill switch

Wireing (spelin) near head stock also a week point

Without having the bike here it's a tough call Dai
By Enelectrax
....... I've had a brand new battery on the bike for the last two weeks plenty of stable voltage going on, and that put an end to my last Enfield issues, just didn't expect to be back so soon with more electrical gremlins.

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