Max RPM's

[Swift Buzzard]

20' Cobia Aprox 4200lbs loaded up....
2000 150 hpdi
Stainless 17p 15 1/4dia Prop (Generic Yamaha)
Turns Aprox 5000rpm

I know that the range is 4500-5500 but do these engines like to run at the top of the range like a mercury, or is running it @ 5000 fine?
The boat is new to me so I don't have verified #'s at this point....
Thanks...

[boscoe99]

Here is advice from the Yamaha tune up specifications manual:

NOTE: It is recommended for optimum performance and engine life to adjust the WOT engine speed to the top end of the recommended range.

I would consider the installation of the same propeller currently being used but with 2 inches less pitch.

[DennisG01]

It's always good to get as close to the upper end as you can as that translates into efficiency, along with avoiding lugging the engine. Although where you are at isn't all that bad, either - but what happens when you're loaded up with people and gear? Another thing to check would be the height of your motor. The anti-ventilation plate should just barely be skimming across the top of the water when on plane.