Motorcycle Repair: electrical problem, circuit breaker trips, amp breaker

Question
I have a 1986 flhtc. My bike has started to shut down at random times and places, (more often in town, but it has happened on the freeway and backroad).All electrical power cuts off and main circuit breaker trips. I have noticed it when I use passing lamps on low beam and also when I have rear bagger running lights on. I have replaced relay and 30 amp main circuit breaker and am considering trying a 50 amp breaker.

Answer
It sounds like you have a short in your lighting system. I would look for the short. If you change the breaker for a bigger one, you might burn some wires. Also, before looking for the short replace the lighting breaker. It might be weak
Good luck and happy riding
Mike