BeauGM

I just installed a Graupner Speed 300 in my Hummingbird. Everything else is stock (battery, Century piezo gyro, pico receiver, stock mixing board). Now the tail just spins when I get close to taking off and spins uncontrolably if I just go for it and lift off fast. Do I need a stronger tail motor? Oh yeah, I put a 12 tooth pinion on the motor. The stock pinion is 11, so it doesn't seem like it would make that much difference. Does it??

-Geoff

kenru

I am running a 9-tooth pinion with my Graupner Speed 300 and it works just fine. I suspect that with the 12 tooth gear, your tail motor can't keep up. My throttle stick is only about 1/2 - 2/3'rds the way up for flight so the 9-tooth still provides plenty of power.