The Bonneville got harder and harder to start on the Elefant to the point where I barely made it home. I then set about finding the problem. Turns out fault number 1 was a duff battery as a result of a short in the charger socket close to it. So far so good. Having put that right I still had no starter motor so set off from the battery, through the solenoid, to the motor with the result I took the motor off, did a jump lead/bench test and hey presto non-moving-parts-type-smoke-machine. I was lucky, Triumphant had one for £150 instead of the £500 the thieving Hinckley bar stewards and Nippon Denso mates wanted. Got it fitted and was rather miffed to find it didn't work. Found another short via corroded wiring (*****y alarm ready garbage by the look of it) near the horn and now got the full 13.8 V at the starter, but still no joy. I always work on the theory that if there is stuff going in but nothing works it's because the things blocked up. Now the meter says the engine is a perfect earth and so's the starter motor case. My jump lead from the starter motor case to the battery negative that now makes the thing run

says it isn't.
So, the Bonneville will get a nice thick second engine earth direct to the starter motor.
Anyone else seen this before? I'm guessing there is some rotten salty **** somewhere that'll conduct mA but balks at A?
Thoughts are appreciated as I hate faults that are cured by luck rather than judgement?
Cheers
Andy