Well I have never seen a 2 wheel one, maybe a "WORKS" model
One time a buddy and I stopped at the Honda dealer. They showed us a scooter, I think about 150 or 200cc. It had 2 wheels up front, I think it turned by leaning like the Kick-n-Go. I think they said they were not sure if they could sell them, as they were waiting on DOT or Transport Canada approval.
Anyway, that never happened & all were pulled off the foor.. be cool to have one, cant remember the name of it..