91 sportster backfire..

[julliani]

I have a 1991 sportster 1200 it has been backfiring after the engine is warm. it only does it while im am giving it a steady throttle. any ideas????

 

[glider]

More than likely it needs a rejetting. What size jets are in it now? Probably about a #42 that should be upped to a #45 and the idle mixture uncapped and adjusted.

Use this as a guide for yours even thou it's for a TC engine..

*Twin Cam CV Carb Rejet Suggestions - Harley Davidson Community