adbz650 wrote: ... electrics have been stripped back.
What causes the melting in the first place ?....
Would suspect that an internal short could cause the melting, or where the coil is allowed for whatever reason to receive continuous battery voltage even when the engine isn't running or in the process of being started (one example would be inadvertently leaving the ignition switched ON when parking the bike).
My Z1 coil failed one time while riding in Yellowstone, where inspection revealed melted black goo oozing from the old original coil. Not roadside-repairable absent a spare coil, but thankfully a Z1 can motor along quite capably while hitting on just two cylinders. And in this case until locating another coil. Which was all it took, and thankfully without being associated with the regulator/rectifier or wiring incident to the regulator/rectifier.
When traveling with another Z1 rider, where
both coils crap out on one of the bikes, a less risky alternative to towing (difficult without a rope, but not impossible) , one good coil may be pirated from the other bike and temporarily installed whereby ride-ability of both bikes may continue.
Then there's always the option of parking and securing the disabled bike as best as possible and continuing as a passenger on your traveling buddy's bike --- a likely fave when it's dark and wolves have started howling.
Shoo, wolf. or I'll sic this Dyna-S on ya!
"Harley Helper" (KZ900 LTD)
Good Fortune!