Tools needed. - Power drill with a known rpm. Most drills state the rpm on the side of the drill, in the specs area. I would suggest a 110-volt drill over a battery-operated drill. Volt meter. Put the brushless motor in a bench vise. Attach the voltmeter to 2 of the wires on the brushless motor. Tighten the shaft of the motor in the chuck of the drill. Now run the drill at full speed. Measure the voltage on the volt meter. Make sure that you are on the "AC" setting of the meter. This is the formula. Motor KV = (rpm of drill / measured voltage) / 1.41 I've tested this method with 2 pole motors and it works well.
