Great data Don,

It looks like the efficiency of the smaller motor is not as good at these currents. The Watts, current, etc., are acceptable if it were a 20x15 or 22x12. I guess it figures, as the length of the motor is less, meaning less torque for a given current vs. the longer motor. You don't get something for nothing. It would probably pull a lot more current with the bigger props and that accounts for John F burning one up.

Jim O