Jerry on the 2nd test what is causing the dip at about 7300 on the vm44 graph?
I do not know without doing more testing. It is a process of elimination until you find it.
First guess: There may be a rich condition caused by a vibrating carb. It could be a lean condition that is foaming the fuel in the float bowl,
2nd guess: The air velocity in the intake may be slightly lower and the reeds may be doing something undesirable at 7300 RPM.
3rd guess: Resonant wave activity in the intake tract may be doing something to the fueling or reed petal movement at 7300 RPM.