Hi,
Wheels aren't rocket science and your severely over complicating
the issue, as are are those called "engineering" students, who
seem to have never heard of "KISS" and real engineering.
The lack of understanding of the real issues in their wheel fixtures is awful,
clueless, and ineptly pointlessly complicated. It isn't complicated at all if
you understand wheel design for different applications.
It wouldn't be hard to mount those wheels directly on the motor flange.
rgds, sreten.