Can't geet past 5500 RPM w/ a 07' 250 HPDI

I have a Z21 Ranger and I can't get the RPM past 5400-5500 RPM. I changed props and still nothing. I understand that the max is 5500 RPM for Yamaha, Yamaha and Ranger tested their Z21 at 5700 RPM. Any input as to what could be preventing me from exceeding 5400-5500 RPM would be appreciated. I have heard it could be the VST filter but don't want to go down the exporatory expense unless that seems to be unanimous.

[boats.net]

If you have the VZ250TLR the operating range is 5000-6000 rpm's. Did you try a smaller pitch prop? Are you running at full trim?

I find it hard to beleive a 21P prop is what I need. Maybe in Colorado since the altidue issues but a 23M in Powell should have been fine. I am confident I have eliminated the Prop issue. Yes about the trim, I played with the jackplate and trim and found the sweet spot in Texas. With a 25M I hit 65 but only got 5500 RPM. If I was thinking I would have put my 23 on to see if there was a difference, was not thinking of couse....

[boats.net]

5500 rpm's is ok, if you like the way the boats performs maybe you should leave it as is.

I want more speed, really hard to run 61 and the same model boat and motor screamed by me like I was sitting still. I should be pushing 70 at sea level and close to 70 at Lake Powell. Not sure what to do.

[jb123]

you should have checked what type of prop he was running.