Aircraft kept having problems turning starter over. I surmised this was because the engine had not run long enough to charge the battery. I charged the battery while in the aircraft, and had no starting problems.
I did a 10 minute (approximate) taxi run while the engine was running. It wants to die, if the rpm is below about 800, especially if the engine is cold.
In addition, the stick needs adjustment - neutral is too far to the left.