Shawn Linn
Active member
Can anyone explain gear ratio for outboard motors, advantages one way or another so an idiot can understand. thanks
gear ratio
- Thread starter Shawn Linn
- Start date
Robert Day
New member
The outboard motor RPM is gear reduced to turn the prop at a slower speed and gain torque.
Gear reduction increases the prop shaft torque allowing a greater load (bigger prop).
A big prop turning slow is more efficient than a little prop turning fast.
I am an idiot and that is my explanation.
R.C.
Gear reduction increases the prop shaft torque allowing a greater load (bigger prop).
A big prop turning slow is more efficient than a little prop turning fast.
I am an idiot and that is my explanation.
R.C.
David Allen
Active member
Try this on.
Gear ratio is simply a factor that relates the rotations per minute (RPMs) of the engine to the RPMs of the prop. Engines have a sweet spot (really a sweet range) where they like to run. The gear ration of the outboard and the pitch of the prop work together so that the motor can run in this sweet spot. The gear ration of the outboard cab not be easily changed but the prop can. A high pitch of the prop will mean more top speed but less acceleration out of the hole. Lower will get you on plane sooner but at the price of top end speed.
Hope this helps.
Gear ratio is simply a factor that relates the rotations per minute (RPMs) of the engine to the RPMs of the prop. Engines have a sweet spot (really a sweet range) where they like to run. The gear ration of the outboard and the pitch of the prop work together so that the motor can run in this sweet spot. The gear ration of the outboard cab not be easily changed but the prop can. A high pitch of the prop will mean more top speed but less acceleration out of the hole. Lower will get you on plane sooner but at the price of top end speed.
Hope this helps.
Shawn Linn
Active member
So following that theory which is better 2.27:1 or 2.8:1 if displacement is close.
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