I don't think a little RPM loss is a bad thing with these motors. With the 18.1X10 prop, you can't run it about 8100 and make the noise requirements. I have mine dialed back to about 7950 or 8000, and have NO power problems. The DZ's have so much power that there are very few times if at all you really need full power. There are certain weather conditions, but I have yet to find one that I was wishing for more power from the motor.

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