Its been a long time
Doesn't know nothing.
Low voltage, however it is caused, can cause that. Best to sort the charging out first, in my opinion.Ok thanks! I’ll do some more testing and check the stator. Would the charging system be what’s fouling the plugs though?
Check resistance across the rotor copper tracks and if OK, check the brushes. New carbon brushes, just a few $.
Check voltage drop across the ignition switch.