2000 Yamaha 90 2 stroke ??

[reptilasix]

What is the top RPM for a Yamaha 90hp? My engine is running at around top 4300 RPM Pathfinder 18 foot. I dont have any idea what pitch prop i have all i know is that it is Stainless Stell 3 blade. What is the ideal prop for this boat and engine.

Thanks

[robert graham]

Same motor as mine. The RPM's should be able to run in the 4500 to 5500 Range at wide open throttle and trimmed up correctly and depending on your boat and prop/setup, you should be able to get around the 5500RPM range. My boat is a large aluminum jon boat so it's not built for speed but I ran mine up to 5200RPM on Saturday, probably could have sqeezed a few more by trimming motor but not real safe with a boat like mine because it will porpoise at high trim. Yamaha Outboard Performance Bulletins give around 3500RPM as the best cruise miles per gallon. Good Luck!