any performance mods such as intake, exhaust, cams, or such?
How many miles on the bike?

 

Fuel flange is leaking

 

So it only effects the engine at 4000RPM? That doesn't sound right. Lots of the vrods have that stumble. I would say it is probably in the tune.

 

Too lean in that range.

 

Fuel flange is leaking. The amount of the leak will determine the problems. Small leak = 4000 rpm stumble.

 

Thanks for replies,guys. Will check it out and let you know.

 

I'll bet its the TUNE the bike pulls after 4000 rpms, if it were the flange it would spit sputter and wouldn't want to go anywhere. :deal:

 

it might be a scared fuel flange......hehehe

 

mine has the same problem. dynopower in toledo worked on it for about 10 minutes and it ran better for about 10 minutes. still has the same problem. my mods are pc3, kn, and a cfr. any ideas?

 

see if you have water at the pc3 connections.

 

i have worked on a few bikes that acted like that.. they were all bikes that needed tuned for a performance modification.. just too lean in that area to run properly.. the fuel flange problem doesn`t just affect the running at a single rpm.. the motor will run badly at all rpms and get worse as the rpm increases..

 

The fuel flange leak on my 03 caused a stumble/miss at 4000 then ran fine above and below 4000. As the fuel flange leak got worse the rpm range affected grew in both directions and then kept getting worse as the leak got worse. Eventually it would not run without missing above 2500 rpm. But that was not how it acted at first when the leak was small.

 

When I had pc3 issues and my dealer talked me into taking off my pc3 and adding the Harley flash to see if it would compensate for my vmod style pipes and high flow air filter it would stumble around 4 grand and then rip all the way to 9. That also happened but around 5 grand when I tried a couple of other peoples pc3 tunes for my set up. So I would guess it's the tune.

 

hmmm, interesting. now i just have to wait till my buddy gets back from the hiatus.

 

Verdict?

 

Would like to know the verdict also. Our 09 DX has a similar , what I call a bobble, burble, miss, since day one out the show room. Dealer just says that this bike does not like to run below 4000. Mods are Bossanni 2 into 1pipe, K&N and V&H fuel pac with proper map.:banghead:

 

That might mean I have a small leak, I have the 4K stumble, but as far back as I can remember it has always had a stumble in that rpm range.

 

from my experience a lot of pipes really lean out a v-rod badly at 4k to 5k rpm... no idea why it was worse at that rpm range but that is what i have seen.. and i have fixed several that acted like that by dyno tuning them...