Help with Yamaha bravo 250

[Bumf]

Hello, my 1986 yamaha bravo 250 has killed 2 voltage regulators and I'd love to figure out why. I have had it off the snow for 2 years now. I stopped running it because it lost spark in the middle of a ride quite suddenly and I could not figure why I had no spark so I changed the obvious spark plug and checked the coil which was bad so bought a working one and still had no spark. Skip to today. I decided I'd try to throw a different voltage regulator on it that came off a different bravo I had laying around and bam! I had spark! So I then poured a little gas down cylinder and it fired like a champ and then I did that again a few times to get some suction on gas pump to hopefully get gas into carb and then it should run on it's own. But after about 5 mins of pouring gas I got gas to the carb and everything was going fine but then nothing. I lost spark again and I'm fairly sure the voltage regulator junked out again. Anybody have wise words of wisdom? I'm defeated by this sled.

 

[GG MM]

Have you bench tested the voltage regulators? Otherwise the best guess I have is to double check your grounds and connections.
Wish I had better advise, I've been tinkering on Bravos for almost all my life.

 

[Maim]

check the wiring harness for rub throughs. has old doo that would do this and i just gave up and sold the sled as no one liked riding it anymore.