On our DA150 we use a servo to operate the choke. On a cold first run of the day, we start with the choke closed and the ignition on, carb at idle. While one guy props the engine the other guy holding the transmitter is ready to flip the servo switch. When the engine starts the choke is opened and momentarily re-closed if the engine begins to quit. This process is repeated until the engine is running smoothly and will accelerate. After the first flight of the day the engine is started by closing the choke, ignition off, and the prop flipped twice. The choke is then opened, ignition on, carb at idle, and the prop flipped once or twice. The engine starts easily.

If you are using a non servo operated choke try starting the engine with the choke closed. When it starts and quits try opening the choke about 25%. It should start and run rich. When it warms up open the choke.