I had the same issue, exactly. Turns out, when I'd put my carb back together after a cleaning and the metering needle clip, which I normally kept on the 2nd notch on the needle (default) had slipped all the way to the last notch.
I took the carb back apart, moved it back to the 2nd notch and it's been running like a champ ever since.
<tried to post this at the end of the thread here but for some reason it posted in the middle somewhere. I'm adding it again here where I intended it.>