Yea, your pilot circuit is not jetted right. First determine if it is lean or rich. Does is pop and rev a little high before it dies, or does is come down to idle and bog a bit.
Let it get almost to idle before it dies, and give it some revs, does it have poor response (hesitation or bogging)? If not, you may be jetted right, but you need to bring you idle up some.
But since you made mods, the jetting is probably off. Did you rejet since you made the mods? If not, I would think you might be lean. But usually when you are lean you know it.
Tinker around with. Jot down where your air screws are set now (so you can reset them back if needed), and try putting them in a turn or a turn in a half. If it helps, you knwo you were lean, and work from there. If it is worse you know you are rich and reste your screws to where they were orginally and turn them out a turn or so.