OK Check this out. Pulled the cowl off the cub and found the pressure line had popped off the tank, that explains why it had to run so rich, no pressure to feed the carb! Got the line put on, put the cowl back on, and it ran OK, two full turns in on the HS, and it ran smooth with a lot less smoke, then it quit. ARGH, pulled the cowl off again, the feed line popped off. I wired them on, put the cowl back on, ran it again, and got the top end smooth, low end is still a bit rough, then it quit, AGAIN! This time the feed line split at the tube. This time I got my soldering iron out, put bulbs of silver solder on the ends of the tube, straightened them out, put new lines on, wired them on, and made sure no sharp bends, and left the cowl off.
Ran out of light to go any further, but I think the slight adjustment to lean on the LS may do the trick, it had quit at idle, and as the fuel ran out it ran much smoother. Transitions are a bit burbely from low idle, so hoping I got this licked. Other than the low idle this is a strong running engine, once I nail the idle down so it is smooth, this will be a great combination, just the right power for the Cub. At half throttle, very scale like flight and sound, WOT it will pull towards heaven! I will be able to hover this one, did it on Sunday for a brief moment, but it was gusty so it got knocked askew, but at 3/4 throttle it held its place.