1982 Seca no spark after rainstorm

[amc49]

Battery is good.

Probably not a coil limitation so much as electronic, many types will not work correctly at under 11 volts. Coils commonly work at volt under where the boxes quit telling them to.

You may have slight trouble everywhere adding up to kill you.

Take big enough wire and jumper the battery directly to coils and see what they get volt wise. That will show you the impact on the coil circuits.

Your starter may be pulling too much amp from wear and pulling battery down too.

 

[Grosjo]

Happened to me a month ago,,, was lucky to have a spare CDI unit..

Jo

 

[amc49]

Yes and possible. Until you check the coils by themselves to make sure they work you are greatly complicating things.

 

[AlexH]

Sorry for the late update, I gave up on this project for a few weeks.
In late september, I had the new coils back on the bike and tried everything to no avail. But two days ago, I decided to try it again on a whim and it started right up, with spark on both cylinders. It's got some other issues (burning some oil and the carbs need some tuning) but the electrical system has decided that it will work. I still only get ~10V on the coils right when I'm starting, but that quickly rises to ~12 once it's running. Thanks for the guidance and wish me luck with electrical demons in the future!