Motorcycle Repair: 97 ultra classic, breath and thunder, thunder header

Question
misfiring under heavy load .Bought the bike with 700 mi.dont know if if it did it before flashing,breath and thunder header.I have 50,000 mi has misfired always bike runs good.I replaced a bad coil recently seems to be misfiring a little more and seem like the front and rear are dropping out were it seemed like it was just the front before.

Answer
About hte only thing youa re going to be able to do is take it in and have a dianostic done on it. That is the only way you will be sure of the problem. In the fuel injected bike there are so many sensers that you dont want to haphazzrdly replay them to find the problem.
Good luck and happy riding
Mike