I have a 1978 lazer that i just picked up. it only has 1,100 orig miles on it. The fuel was pretty old and I cleaned it out and took the carb apart to clean it. It will not run unless the choke is on all the way. It has great fuel flow and the carb seems 100%clean. I sprayed carb cleaner around all the connections to see if there is an air leak and there seems to be none. The adjusting screw ha sno impact what so ever if you turn it or even take it out. what am i missing?