A simple continuity check will usually show a duff one

Yes but not always. I once had a (dare I say it ? ) MZ that would stop after 1/2 an hour, with low battery. Checking the stator on the bench and in the machine showed nothing wrong, but one of the windings had the insulation worn off and it shorted to the frame only when the engine was running, because of the vibrations.
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Poul
"If Life Gets Boring, Risk It!"
MC21SE, KISS box
MC21SP, HRC box, racing loom