50:1 approx,change plugs ,non-ethenol premium gas,and Its still a bear to flip start,In fact it won't,I have to try to use a starter ,choke it and then it will fire.it will restart will a flip or two unless it sits for an hour. My question is what can I do to improve its starting ,without buying some giant stater and dragging out a car battery?I have a nice new DA50 powered P-51 and I really don't want to chew up the spinner tryin to get it started .Any suggestions would be greatly appreciated...