I went up to the DC 3-Day with a motorcycle crew member -- he had a 45-foot Cyclone RV that had a "garage" built into the back. It was accessible from inside the RV, and outside side door. But, the whole back wall swung down so he could ride his motorcycle right inside. It had hold-down straps for the bike. My mountain bike felt so macho strapped inside right next to the big bike! 
The Cyclone is what he was calling a fifth-wheel? It was towed behind his truck.
For 3 days, I get to part of a thousand other journeys.