Hi Will - I have always used governor mode, simply because I don't have a laptop and want to use the timer to make on the spot RPM changes at the field. I set the magnet pole setting at 14 because the motor spec sheet calls out no. of stator arms=12, no. of magnet poles =14. I guessed that the stator had to be the armature windings on the fixed part of the motor. So the magnet poles have to be the magnets in the outer rotating can? When the motor is cogged over, I clearly count 12 steps. Might this explain it? (14/12 x 9050 = 10,558). Most important, your experience seems to suggest that if the system looks staqble, it will give adequate flight performance by just tuning the RPM to give good results in terms of flight trimm, and ignore the discrepancy. Any thoughts?
Hi Dennis - My guess is that the timing wouldn't affect the RPM discrepancy. I do plan to move it up after I get things flying. One thing that might be of interest is that the front end of this airplane is open, and it has only a spinner nut the width of the prop hub. Accordingly, the cooling holes in the motor bell face directly into the airflow. There is also a big air exhaust in the cockpit, with a cutaway canopy to operate as a rear facing airscoop. Apparently the cooling is fully functional, as I couldn't detect any difference between ambient temperature and the bell temp after the first few test flights. I have an IR thermometer, and elected not to bother with it when I felt the motor on the first flight. It was a smoking flight, 3.9 sec. laps, yet the motor stayed way cool. We shall see if advancing the timing makes it run any warmer.