I ran into these guys last year outside of Moab. I was riding my moto, and they were loading their motos(all 12) into this 40 footer, that had more invested in the top-deck than the purchase of the bus. They were finishing up the week and were headed back to Canada, wish I had more time to spend with them.
I was hoping to find some evidence of these guys here but only founda mention from a friend
The website no longer remains, but they tweet https://twitter.com/ZBusCaptain