Help! 2005 Sporster, carburated (but some of you already knew that) after acceleration it backfires. Just started. Cause????

 

Exhaust tight? Battery Cables tight? Hi Octane Gas? Any other symptoms? Idle speed change, running rough at idle, or ruogher than normal while warming up? Also can you recreate it while not riding? (Rev her up to 5 k, then let off) Did flames shoot outta yuor exhaust with the back fire? Help us out here.

 

Changed exhaust lately? That is when you usually start to notice it!

 

everything is tight. it only does it when the weather is cold. i cant make it do it when im just sitting. has to have a load on it.

 

Sounds like it may be an intake or exhaust leak as when it is warm out everything expands.

 

play with the choke and you can tell if it is lean or rich. you may have a issue with high speed jet. simple to remove and clean the carb out