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fish2live

04 johnson 90 4 stroke?

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what kind of rpms should i be running on this motor. i am buying a boat with this motor and at wot it is around 5900 rpms seems a little high for a 4 stroke. should it be in the 5500 range?

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i answered my own question it's between 4500-5500 now my new question is it has a 14x19 would a 21 pitch prop get me down 400 rpm's?

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In theory for each 1" of pitch change it should move your RPM +-200, depending on the direction you take. With that being said, each prop is a little different so your best bet is to work with a dealer that has some test props to find what you like.

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I'd try the 21... you may need a 23 with the high gear case lower unit that suzuki (who made the motor for johnson), but your holeshot may suffer a bit with the 23.

marine_man

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Fish2Live - I have this motor and I believe I currently have a 13 1/4 x 19 Hustler aluminum.

I am not at WOT when I hit 5,500 rpms so you may want to look at a 21.

I've thought about swapping props, but I like the holeshot I have and I'm rarely on big water so a few mph top end isn't of great concern.

Enjoy the motor. Mine has been flawless.

DB

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