I recently bought a 2006 Sportster XL 1200 Custom with only 256 miles on it. When it is completely warmed up it will idle on its own but just barely. To me, it seems like it idles a bit low. Sometimes after it is warmed up and I am out riding and I hold in the clutch to prepare for a stop it will die on me and I will have to restart it. With no choke and at idle, if i give it a little gas to take off it will stumble and want to die but if i crank on it it revs right up. If i have it half or more choked and give it a little gas, it has no stumble at all. Could I get some advice on what could be causing this, perhaps running to lean, carb needs cleaning, ect?

 

An 06 with less than 300 miles-Id say it was just sitting in a garage collecting dust. The carb probably wasn't drained and the fuel gummed up the carb. I'd take the carb apart and clean it, well jets are cheap-replace those instead of cleaning. Check the float needle and seat also. None of that is hard to do,get a manual if you don't already have one.

 

First, i'd run a few tanks with Seafoam through it before i started tearing it apart. I bought mine last year with only 900 miles on it. It ran a little ruff and didn't idle well. I ran a few tanks of premium non ethanol gas with Seafoam added. Cleared it right up. I still add Seafoam every once in a while to keep her cleaned out.

 

+1..... I would also look into rebuilding the carb.

This site HERE will help you get the best out of your carb.

 

I'll bet you one hundred dollars the slow jet is blocked.....I had the same problem ....stumbling on take off.....It looked like a piece of the glue that they used to hold the gasket in place got into the slow jet...Cleaned it out and all was fine...You might want to go up one or two sizes on that jet also that will take care of the leanness and high heat of the stock setting....