Sounds like fuel filter to me. Will it rev past 4000 in neutral but not in high gear. It's under load and not getting the volume of fuel needed. This is usually how a fuel filter will act when clogging up. Filter is cheap and that's where I would start before I go into anything else.

 

actually, it also might be sumping...usually that doesn't happen unless you have bee in the cam case, but you never know.. if it is sumping you 'should' see foam in the oil... take the bike for a ride, make it act up (i.e., rev it up) and pull over, shut it down and check the oil, if it is all foamy that is not a good sighn...

 

That would set a code and the OP says there are none.

 

Good point, thanks. Back to fuel system.

 

Nobody's mentioned this yet, but as a 40 year mechanic, and based on what you're saying, I'd go straight for a restricted cat if fuel is good.

If you're running catless headers never mind.😀

 

Good one: being that I have no cats, I never even thought of that, but have had to cut out or replace cats in cars many times for that reason. Kudos my man. I would have thought that running rich enough to foul a cat would also have set a code though.

 

I had a 2002 FLHTCUI with 115.000 miles that had a similar problem when returning from Sturgis years ago. It would just flatten out about 4000 RPM in any gear. Stopped at a dealer in Iowa and they said that they checked the fuel pump pressure and compression and all was good. Then they told me I had worn out cams and to ride the hell out of it until it broke because I had the extended service plan. Rode it back home (1500 miles) and took it to my dealer. When the tech checked the fuel pressure it was good at an idle but it dropped off when he took it down the road. He replaced the fuel pump and the bike ran like new. Just my experience. I still wonder if some of the gas I bought along the way contributed to the problem.

 

Check crank runout?

 

well OP, have you changed the fuel filter? checked for sumping? what about the clogged cat, have you got one?
the suspense is killing me.


Now you guys that avoid 4000 rpm, what is that all about? stock these are around 5800 max, stage 1 @ 6200. are you telling me that you shift below 3000 and ride like the proverbial old lady driver. It may not be a crotch rocket but the power band is 3500-4500 for acceleration purposes.
good grief if you don't hit the rev limiter once per month you void the warranty!

 

My 06 Electraglide came with a torn oil pump O-ring that filled the crankcase with oil. After adding the lost oil with 50 miles on the bike,it was thought it had come low from the factory it only took a year of complaining and being told everything checked ok, for the shop to finally called the factory. They suggested they check the sump and then fix the oil pump seal.
The bike pulled great from idle to just over 3k before the revs bogged. Simple to pull the sump plug with a catch pan handy.