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RPMs

"K.T. your max wot should be 5

"K.T. your max wot should be 5600, so optimal would be 5400/5450. Optimal wot is where you have a small safety zone against over-rev, but the motor still produces max horsepower. When selecting a prop and trimming the boat this is the rpm you should shoot for.

You will find if you set it all up in the spring or fall, during the middle of summer you may lose as much as 400 or 500 rpm at top end. This is due to humidity and air density. For that reason you should re-prop (again) during the summer because it is unhealthy for the motor to fall out of it's max rpm range - 5000-5600 on your model. Falling below 5000 at wide open can cause damage to the powerhead.

The importance of props are often misunderstood and overlooked - every boat that is used for more than just the summer season should have at least 2 props of different pitches..."
 
What is the maximum rpm for a

What is the maximum rpm for a Mercury 125hp off shore 1997 motor
 
"Bruce, the WOT range for your

"Bruce, the WOT range for your model is 4750 – 5250. Your optimum wot rpm would be about 5000/5100 - it is at that point your motor develops max horsepower and still leaves a little wiggle room to prevent an over-rev.

Anything below 4750 rpm at full throttle (if the motor is running properly - meaning the rpm is not restricted due to mechanical issue) would be caused by "too much prop". That is a dangerous situation which will severely shorten the life of your motor."
 
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