rotor gone completely dead?

Wiring?

There are kits for Japanese bikes that add a relay taking battery power directly to the coil circuit. The purpose is to use the stock electrical wiring which may have degraded over time to carry only the control signal to the relay and let the high current flow without resistance to the ignition circuit. I have read an article with the same sysmptoms as you have, they tried everything only to find that there were bad contacts in the control switches and in the wire connections so rather than redo the whole wiring it was easier to install a relay. A little 12 volts SPDT (only need the NO contacts) relay like https://www.addison-electronique.com/ca ... s_id=90276 will work very well. If you want I could draw it up and post it as a picture.

You could try the same thing by running a wire from the battery directly to the coils, add a switch for convenience if you like.

BTW, are you on positive or negative ground? (not that it matters, just to make it clearer if I have to draw something up)

Jean

Perhaps one more check you can do is check the coils again--this time loosen the clamps and see if maybe they have been overtightened. If they are crushed, sides are dented, this can cause them to overheat after running awhile. They may still work ok but when reinstalling only tighten the clamps enough to keep them from spinning --twist them while tightening--stop when you can't twist them easily any more.
If you can, fabricate some rubber shims and place these in the gaps on the clamps and drill holes in them for the bolts to go through.
This will prevent the clamp from crushing the coils and also put tension on the bolts to keep them secure---some Blue locktite works well here also.
This has happened to a friend of mine on his bike one day. I loosened up the coils and it fired right up and ran well the rest of the day. He did replace the old lucas coils afterwards with the German Coils.

Joda