Can anyone out there help me? I work in a bike shop in London and my best mecahanics are scratching their heads on this one. My 2005 sportster has begun to stutter when trying to pull away at lights and junctions etc. It only happens when warm (after 2 or 3 miles). I have checked the coil (I swapped with a collegue), plugs, cleaned the carb and replaced the carb inlet seals. Could it be the crank position censor? Is this an expensive fix?

 

Have you checked for DTC's? The crank position sensor will usually throw a P0373 or P0374 code. If it is the crank sensor, it's about $50 US and takes 10 minutes to change.

 

Just had this happen with a Sporty at the shop. Same story, ran great until it got warm and then it would stumble leaving from a stop, then it would get worse and die almost every time you idle at a stop. Enden up being a bad ignition module, you may want to check that.

 

I don't know much about Harley carbs but if it was a carb'd car I would check the accelerator pump in the carb.

 

Cheers Charley. But what's a DTC?

 

Thanks mate. By ignition module do you mean the doohicky thing that lives under the seat?

 

DTC= Diagnostic Trouble Code. DTC's get stored in and can be read using the speedometer. There's a sticky thread at the top of the sporty main page under DIY that will walk you through getting and reading the codes.

 

As a start, I might check the carb and float level, sounds like its running to rich when hot, like the choke was on.

Brett

 

Do the bikes with carbs have dtc's?

Brett

 

Yes.