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posted to rec.boats
Injam
 
Posts: n/a
Default I'm trying to understand propellers

But you would not over rev?

"Harry Krause" wrote in message
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Injam wrote:
If you are testing your new boat and find that it does not achieve
recommended maximum RPM at WOT. That would be bad for the motor right?
Too much load. Then you would change to one that is a lower gear so to
speak. And if you over compensated and the motor went over the
recommended maximum RPM at WOT. That too would be bad for the motor,
right? Over revving. When testing should you take it to the recommended
maximum RPM and see if you have any throttle left?



Ideally, with your boat properly loaded and trimmed out, your engine RPMs
should be between the middle and upper end of the max RPM range suggested
by the manufacturer. As an example, one outboard I know of has a
recommended range of 5500 to 6000 rpm at WOT. If I got 5300, I'd probably
look for a slightly different pitched prop. If I got 5800, I'd be pleased.