Rosborough 22 Inboard Wheel Size

JSousa003

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This is my first post, but have been following many threads and learning lots from everyone's builds & projects.

Over the past year I have repowered a Rosborough Sea Skiff 22 with a Yanmar 4JH4-HTE 110hp inboard. The current wheel I'm turning is a 16x17RH with a #4 pitch (-0.63). I am currently able to turn 3500 RPM at full throttle and the motor is designed to turn 3200 RPM.

I have been advised to change the wheel to a 16x20RH with a #3 pitch. What do you all think about the wheel size & the suggestion?

Thanks for all your help in advance.
 

Sailorgp

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vou've been advised to make an awfully big change to your wheel in order to drop your wot a slight 300rpm. I'd go with a 16x18 wheel which would theoretically put you at 3300 wot rpm. Being 100 rpm over propped is actually good for your engine.
 

JSousa003

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Thanks for the input. After discussions with Michigan Wheel I settled on a 16x19 with no cupping. Still about 150rpms over when fully loaded with gear, but I can live with that and hopefully once the coolers are full of fish that will be helpful.
 
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