Join Date: Apr 2012
Location: Boyertown, PA, USA
Still not an engineer, but I gotta think your starter is drawing too much. Or at least too much for the solenoid - which is just an electronic switch - thus fusing the hot terminals in the switch together. You probably need a starter rebuild after this episode anyway so I would also take a look at the entire circuit - wire size, dirt, corrosion etc and get the system back to zero zero. Then I would run a volt/amp meter on it to see what the draw is while starting and compare to what the specs of the solenoid are.
Last year I rewired my Hailwood's starter circuit with thousand strand, floppy, silicone encased primary wire and ran the ground from the batt using the same stuff to the engine. I was losing almost 2V at the starter before and now the loss is minimal and the bike starts a lot better. Not the same problem as yours but I can't help but think there is a relationship here. An elec motor will continue to draw and draw and draw without limit against mechanical resistance until it blows up, seizes or ruins (ie fries) the components in line. A shoddy circuit will exacerbate this.
Failure is not an option 1995 Duc 916,1994 Bim DB2,1986 Duc MHR Mille, 1974 Duc 750 Sport, 1965 Duc Monza