Oblivious, I'm currently in the process of removing the counterbalancer shaft from my bike also. Main reason is to reduce rotating inertia hence acceleration rate of engine will be marginally better plus of course there are marginal power gains to be had from the reduction in bearing friction, intermesh of gears, windage.
My concern is the magnitude of the "unbalanced "vibration.
The bike will be used primarily for track ride days and some street use.
Muzzy sell a replacement for the ZX12.!!
In regards to the oil supply , that definately needs to be addressed which I have yet to look at in detail and would interested if others have machined up a dummy replacement shaft which isn't driven.