My breaker went bad on my 99 roadking classic it had a 30 amp breaker on it per harley i installed a 50 amp breaker then after 20-30 miles my check engine light came on was throwing code 54 which is ecm failure my question is could resetting the ecm after changing the braker fix my problem or do i need to change out my mm system to delphi the bike only has 11,000 miles on it

 

I'm not sure if this is your problem or not but why would you replace a 30 amp breaker with a 50 amp? Are you sure the breaker was bad or was it doing it's job and tripping because of a 30 amp load or short? If it went to the ECM, you may have fried it with a breaker higher than what the ecm can take.

 

 

Sure, try resetting the ecm, at this point it can't hurt.

But, really, I agree with the guys above me.

You replaced a 30A breaker, meant to protect your wiring and electronics, with one with 60% more capacity. Nothing good is likely to come of that.

 

Guys, did you actually read the OP's post? He went to 50A breaker as per HD's recommendation. Rides of that era had problems with the crappy 30A breaker and HD recommends installing their 50A breaker. It's not going end up in a fire. Still have the 30A on my 2000 and at 50k miles it's still working but when it does fail I'll go with the 50A and also ditch the weak 2-wire stator/regulator and move up to CE's 3 phase.

OP, if you find no resolution with resetting the ECM I'd suggest either replacing the MM EFI and going to a carb. Install a DTT ignition, mod your tank with a petcock, plug the 2nd fuel outlet, change your harness and install a Mikuni or CV carb and matching manifold. This would be much less work and easier tuning than installing a Delpi EFI. That it unless you already have access to a full Delphi system and a Dyno tuner.

 

 

I had a similar issue with the circuit breaker on my 2000 Ultra Classic. HD issued a recall in the early 2000's
for the main breaker and a local dealer replaced my circuit breaker under the recall notice. No problems with
shutting off since.

 

I was skeptical about the 30 to 50 thing but a Google search confirmed what you said. I'm aware that engineers build in a certain safety factor into their wiring designs. But a factor of 60% seems outrageous to me. It very much smacks of putting a penny behind the old screw in house fuses.
I think, if it were my bike, I'd convert to a 30A Maxi fuse before I'd put a 50A anything in.

 

Let us know how you make out

 

We really have minimal information.
What we know:
You have a 1999 Road king Classic with 11,000 miles
You changed 30 amp breaker to 50 amp breaker and are sure breaker is good.
You have a code 54 ( ECM failure).
What we do not know:
Was bike running OK before?
How long have you owned bike with NO problems?
Any changes from stock?
My guess:
You changed breaker or wires to breaker with battery connected OR since previous breaker was "bad" the code 54 could have been caused by someone ignoring the bad breaker and pushing the situation over and over and over and over again, causing damage to ECM
Is Bike running OK?
If so, turn off all switches, then disconnect both battery cables and let it sit a few minutes to de-energize....open switch for 1 minute and close switch.
Then reconnect both battery cables.
I will also have to guess that you have tested the battery on the bike and are 100% sure the battery is good.