Is it a 2 stroke or 4 stroke?
The rev limiter on a 50hp 2 stroke Yamaha is 5800 rpm, the rev limiter on a 50hp 4 stroke Yamaha is at 6250 rpm.
That 2 stroke motor makes max horsepower and torque as close to that 5800 as you can get and the 4 stroke makes max hp and torque at 6249 rpm.
You are pushing a very heavy hull. You may turn a 14 pitch, just won't turn it efficiently, it will lug the motor.
You can prop the motor for an empty boat or a loaded boat, not both with the same prop.
We run 13 pitch Turbo Hot Shots on 50hp hot rod Tohatsu's, same gear ratio, and turn them about 6200 rpm on a loaded boat. They run in the low to mid 40's with a hunting load.
Again, do you want to prop it for the 2% of the time you will run totally empty or the 98% of the time you will run loaded?
If you're turning a 14 pitch 5100 empty, you are further off than 1" of pitch on a loaded boat.
D
|