My 2010 sportster runs rough just off idle. In town at 30mph it spits and
coughs all the time. I bought this bike brand new from a dealer and have
experienced this since new about 1 year ago, yes it still is under warranty.
it has 4k miles on it and 1k was performed by me. This is my 1st harley and
want to make sure this is not considered a normal condition before I go talk to the dealer. the bike runs great at idle and under a load on highway, but very annoying in town. I installed teds v-twin slip ons on it at 1500miles other than that it is stock

 

did it start acting up after you put the pipes on???

 

Good question, slip-ons will make a difference - but not that bad. What do your plugs look like?

It sounds like it oughta still be under warranty. Take the dang thing in.

 

no it was doing that before the pipes, also fuel quality does not effect this condition
88-91 octane little difference

 

really that is what i needed to hear. I have a sparadic fuel light that comes on,gonna take it in and now i will tell them to address the runn problem too. thanks

 

Thing about that fuel light - it is naturally spasmatic or whatever you called it. On my '08 (4.5 gal tank) it'll flicker off & on when I'm down to 2 gallons especially under acceleration from a stop, then stay on constant at about a gallon and a half or less.

 

And when it's down to 1 1/2 gallons or less it'll cough real bad in turns or acclerating from a stop. Fuel must be getting away from the pick-up when low. Stll doesn't sound like your problem though does it?

 

My bike had a low end stumble until
I put on the x14ied. That cleared it up. No problems related to turning or fuel starvation until about 40-50 miles after the reserve light comes on.

 

mine will come on 5-6 miles after a fill up, tired of doing math while i ride!

 

At 30 mph what gear are you in? You might be lugging the motor. Maybe going down one gear will bring the revs up and smooth it out for you.