Well I'm back for the last time on this problem.
The little black electronics box ( 32910-24B10 under the seat that is for the decompression solenoid,) which has 6 flat brass connectors, had packed it in.
We opened it up & long ago there must have been water in it. It is sealed to prevent this, so is a mystery. The solder blobs on the circuit board had corrosion.
The guy said the timing of its death was just a coincidence. I paid him 120$ & bought a new one - 145$ & yesterday all was made operable.
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I have to share something now before someone else has great head problems as I had.
I bought this as-new bike from afar because it was cheap & lowish Ks. Cheap because it had a disgusting surge (I didn't know) that nearly made it un-rideable. I have been toying with selling as-is for ages. The surge was bad, mostly in the first 1/4 of the range of every gear but discernable throughout.
Mechanics could not fix it.
The last one, was a great guy (Duzgo) just retired, not because of me though
with a fantastic reputation. He placed an old savage needle in the carb & had it set to idle very fast & said not to let it get too low in any gear. Everyone did their best but it wasn't PETROL surge, it was ELECTRICITY surge!
Never imagined this was possible myself. There is no evidence whatsoever of any surge now. It is smooth as silk. I hope not too many are fooled by this too often. What a joy to ride Francis with those old pullback bars
I guess it will need a carby tune, but not sure. I put the idle back to normal.
Thanks everyone & the mods too. I have a ton of reading to do on this great site.