Hi @simscale7yahoo and @jousefm, I am not sure what is happening with the MRF. Looking at the latest project link from Jousef, it seems an MRF zone is created but with an additional shell? I think the MRF is too tight to the tyre, in the FSAE project the MRF was in the dish of the rim, allowing a solid to be able to mesh around the spokes. Here we have the MRF almost flush with the spokes. I think it would be worth extending the MRF symmetrically along the spinning axis, This will allow us to a single MRF.
Then as suggested a rotating wall can be applied to the outside of the wheel.
Hope this answers your question, and let me know if you still have trouble.
Kind regards,
Darren