I bought my 1994 Road King April 2014. I have had no problem till the last couple of weeks. I crank it and let it idle 5 or 6 minutes. When I leave out it sputters, coughs and backfires for the first 3 or 4 miles. once it warms up at that time it is fine. It seems to be taking longer to warm up than it used to. Is there something I need to try to straighten it out? What am I missing? Any help would be appreciated.

 

Sounds like you need to clean out the carb and set the idle mixture screw again.

 

ThanksHackd, I'll give that a try.

 

Check for intake leaks before pulling the carb,
not knowing the history of the bike, probably should just replace the intake seals, clean carb, replace fuel line if it's old, and pull the petcock and clean the screen,
if the screen is full of debris, rinse the tank out too.

 

All great advice, Another thing to check is to see if the carb is tight against the manifold. your carb to intake seal may be going bad, I'm on my 3rd one on my 1997 flht. It will idle fine, but will suck air behind the carb under load and will give you similar symptoms to an intake leak at the heads. I find that sometimes it would settle in, but once they get too bad they just wont stop sputtering, coughing etc.

 

Sounds exactly like what I've dealt with over the last couple years on " rare "occasion. My bike will run amazing and then all of a sudden like garbage. Spit and sputter so bad that she won't go. I'm no mechanic, but (amongst what others have posted) fuel is the simplest cause and also a possibility. Pay attention to where you fill up. I know the station I used to frequent was confirmed to have contaminated fuel on occasion. Hopefully this is your issue. Pour some carb cleaner in your next couple fill-ups and start there before more costly repairs.

 

Thanks everyone. A lot of good ideas. I will try them, I will post when I find the culprit.