for 3d you move the batt to the rear of the radio bay. and for sport you move it to the front. the exact messurements will be in the manule. and yes this motor will hover it. i have flown one with a os 61 fx saito 91 fs and saito 100. and each motor was great! nothing beats a saito 100, but the 61 had tons of power. it is a 40 size plane after all.