View Full Version : Sporty Choking (with vids)

06-16-2014, 7:13 AM
I have a 2006 Sportster low. Recently it has been sounding like its choking and on the verge of sputtering out(it has started to sputter out as of recently). If I open up the choke it either does very little or at the best makes it sound like its idling if i had started it with the choke closed. Does anyone have any idea what could be causing this and if so what can be done?


06-16-2014, 7:13 AM

here is a second example. These actually sound better than what i was getting today.

06-19-2014, 1:30 AM
When was the last time you cleaned your carb? Maybe the idle passage is a little bit clogged up. I'm not really sure, but it seems that a carb clean is always a good place to start when the idle sucks. What's it like off idle?

06-20-2014, 2:22 PM
One of those videos was me at a stop light after riding it for a bit. When actually riding it there is some struggle. like with throttle open it seems fun but once i start slowing down it feels like it is quickly starting to struggle or about to kick off at any point. I tried cleaning the carb with sea foam spray and that gave it like a 5% boost in performance but was still really bad. I pulled the spark plugs out and they were all sorts of black. cleaned them some and that helped but still not up to snuff on account i could really get them to where they needed to be. replaced the spark plugs all together and a vast vast vast improvement. That being said I still feel like its not running at a hundo. maybe like 85% but i cant really tell because i have ridden for about 2 weeks slowly going downhill that I cant tell if everything is fine.

06-20-2014, 4:37 PM
So if the plugs are black that means it is running rich. Have you made any changes to the bike between the time it ran okay and now? For example, have you changed the air cleaner or exhaust? Did you adjust the idle screw? I think something has caused your bike to run rich. If the carb is clean, the air cleaner is clean, I would try to adjust the idle screw. make a note of its position, and turn it a quarter turn clockwise. That will lean it out. When you adjust the idle screw you want to make very minute adjustments. So make an adjustment, ride it, and then make another small adjustment if needed. Be really careful though. If you lean it out too much, you can damage the engine. Might be a good idea to check your jetting and post it on here too. I'm no jetting whizz but I'm sure someone can help you out. Oh, also, check your spark plug gap. I think they are suposed to be gapped to .038" .040" It could just be an ignition problem rather than a fuel problem

06-24-2014, 11:11 PM
Have you checked for vacuum leaks? I had the hose that connects to the V.O.E.s develop a crack which gave similar running conditions. Black plugs could be from using the choke so much to test.

06-25-2014, 4:19 PM
A cracked vacuum line from the manifold would mess with the VOES switch, as well as shut the diaphragm on the vacuum operated petcock so no fuel hits your float bowl. The choke being pulled out would increase the amount of fuel and air going through the manifold, and might cause the bike to run better. After that I'd check plugs, wires, and the coil if you or a friend happen to have a known good one lying around.