I have no idea how to go about balancing a single rotor.   Would it
be accomplished by adding more balance weights to the e-shaft.  How
would one do this?   Is  it done while the e-shaft is balanced
between two knife edges.   Perhaps my question reveal that I am
missing the point altogether.      ???????? Jerry

Knife edges give you static balance only.
It is not easy Jerry. You need to know exactly where the center of mass is
in a counter weight. In other words how far the counter weight is from the center of the
rotor along the axis of the e-shaft. Perhaps the easy thing is to send it
to a guy here in So Cal that balances rotary engines
and then copy exactly what he comes up with. Call Mazdatrix for the
name of the guy they use.

http://www.balancemaster.com/Balancing_explained.htm