Motorcycle Repair: 75 Honda Trail 90, honda trail 90, path of least resistance

Question
I am having an electrical problem.  Battery tests good.  When the headlights are on running down the road at half throttle or better the engine cuts out almost in synch with the signal light when it is turned on (L or R). When I try to rev the engine (sitting still) with the signal lights on the engine cuts out.  It will do it to some degree with the lights on or brake light is on but not as significant as when the signal lights are on.  All lights off and the engine revs up.  Any ideas?

Answer
Lance, it sounds like you have some high resistance in the ignition system somewhere.  Check the mounting of the coil to make sure the frame under where it mounts is clean and has a good clean ground.  If that's okay check the other connections back to the ignition switch.  If there's high resistance between the battery and coils, the current will take the path of least resistance which in this case is through the lights.

Regards
Rich