Saito 40

"stops in mid flight" "When I restarted it about ten minutes later I had to turn the engine over several revs with the electric starter. Usually it would start on the first rev when restarting " Indicates the motor the motor has leaned out in flight, got hot and used/dried out all fuel remaining in crankcase. Try taking off a click or two richer on the needle valve or checking for air leaks especially if using a Du-Bro or similar fuelling valve. Fuelling valve may have a stuck shuttle or need new "O" rings which should be replaced each year or two - especially if stored for any length of time and dried out.
regards Alan T. Alan's Hobby, Model & RC Web Links