engine won't rev up

[hogmandon]

06 RG, 98" heads from Don, 50mm TB, 10.8 to1 210ccp.
This just started bike will not rev over 5,000rpm. I just changed the filter in the tank a few months ago. All lines in tank have been replaced. Usually it revs up so fast I have to think about shifting as soon as I crack it open. Rev limiter is set at 6200. Was wondering if the fuel pumps get tired and can't keep up. Bike has 129,000m on it. In my truck it started to run poorly and then just quit and the fuel pump had to be replaced but that had over 300,000m on it. Any ideas

[N-gin]

Sumping. You'll need to check the oil amount in the cases by draining them into a measuring cup.
I've seen the o ring go bad on the case to pump and it does exactly what your saying.