I have a 2003 EFI FLSTF 70,000 miles, giving me fits. Start it up cold, it idles fine. Take off immediately, and when accelerating it stutters/hesitates in 1st and 2nd gear, sometimes 3rd until Ive ridden it about 1/4 mile or so. Light to medium throttle. If I go wide open it seems to clear up. After 1/4-1/2 mile it will not do it anymore unless shut off and cooled down. Has SE203 cams and V&H Bigshots with Powervision tune. I installed stock tune and it still does it but runs worse. No codes. I am at a loss. It has been doing this for a long time, since cams, lifters, tensioners and remap done. Powervision tech service is no help. I have tried adjusting warmup fuel, It makes no difference with problem. Seems like it is an issue with the bike, not the tuner. Watching guages on powervision I see no issue with tps, map, et all seem to be linear and working fine. Fuel pressure and filter have been addressed and checked. Please help.

 

You state that you take off cold, maybe let the bike warm up longer.

 

Try cleaning the IAC.

 

Have you checked the intake seals? Probably not them but takes 2 mins, is effecively free and will help eliminate that if need be.

 

If it totally clears up after 1/4-1/2 mile, and runs perfect until it is cold started again, it doesn't sound like a mechanical defect to me...

If it has been doing it since the cam & remap has been done, sounds to me like the warm up portion of the tune needs attention.

Or..... could be just your specific engine w/those mods needs to warm up a little...

I have a 2003 Heritage w/ SE203 cams, big bore (95") w/headwork and that bike runs very well... However, I always start off slow giving it time to warm up before pushing it at all. I haven't noticed any hesitation with light to medium throttle while warming up... so I am going to bet on the tune...

If you used FuelMoto to buy your PowerVision tuner, you could do a data log and send it to them with your issue and they could address it with modifications to the tune you are using.

I have had luck with DynoJet too. There were certain people you could send your tune to via an email, tell them your issue, and they would send back a modified tune to address your concerns.

I have never tried to fix a tune over the phone talking w/a tech person. But I have had great success sending a tune to both places and received a modified tune that addressed my issues...

Good luck with your issue, let us know how you eventually get it resolved..

 

Also check cold compression on both cylinders, and definitely check out the map. Also check for any vacuum leaks. Lastly check the engine temp sensor.