I have a 1998 Ultra and the 50 amp breaker under the seat tripped,And keeps tripping within 15 seconds of running unless I unplug the stator than it works fine. I tested the stator and it tested fine and it still charges fine until the breaker trips. I swapped out the voltage regulator and it had no change. It looks like it needs a stator but with it testing fine and charging fine I don't want to just throw parts at it. Any suggestions?

 

Sounds like what it needs is a new 50A circuit breaker.
Or do the conversion to a regular fuse. I think HD sells a kit.

 

​​​​​​​...and circuit breakers have been known to go bad from time to time. ..