I looked at my carb today. The back barrel was not working. I checked, and the linkage was hitting the intake manifold. I took it off and cut the piece off that was hitting the manifold. I drove it, and it seems to be more responsive. I will find out for sure tomorrow on the way to work. There is a hill that always brings the speed down 10 MPH. Hopefully this will work.

How are you checking the second barrel? It is opened by a vacuum diaphram unless it old enough to have a mechanical seconday.