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.