Try a new plug, gapped at .020 instead of .035. Use a good plug, not a crappy Chinese one like the engine comes with.
There's a list of plugs around here somewhere.....Autolite 425 or 4093 for starters.
See what happens, it's under two dollars to find out if that's it.
BTW, let me get something straight, does it run O.K. once you get it going and dies when you are off the throttle and pull in the clutch? Or does it run generally crappy all the time?