Keep the ignitor on it and adjust the low end per the instructions posted here earlier. If it slows down and dies after a minute, then it's probably loading up, so lean it some and see what happens. If you can get it to idle at 3000 or so without the ignitor, let it run like that for a few tanks full. Remember, this engine is still breaking in! It will improve with a little time, and you should be able to gradually zero in on the exact regulator setting, and begin reducing the idle RPMs until the regulator drops out and it's running just on vacuum. Take your time, make small adjustments, and once you get it to idle at 2500 or lower, concentrate on the air-bleed screw until you get it to idle smoothly. Often just a touch to the regulator screw will make all the difference in the world, and once you get it tuned, it will purr every time you start it.

It's amazing how often another part in the fuel system winds up being the cause of a YS that isn't running right. Just like my 140 was at first.

Good Luck!

David