I'm not sure why you are trying so hard to avoid a trailer, but in any case, I don't think sliding a TC forward would be a problem carrying it. I do think you'd have to ride with the tailgate off.
I dirt biked a few times with friends in the Class A that I had. One problem that I didn't solve was how to deal with the dirt and extra gear required to dirtbike. For that reason, I think you'd be far better off with a Toy Hauler TT. The bikes would be protected from weather and could stay loaded which would be a big plus as far as I'm concerned.
