Why not just use a smaller tire? I found mine in the woods while walkin one day. Carried it home about a mile and a half. Some guy actually stopped to ask if I needed help. OK buddy I'm carrying a fuckin tire, not changin one.
I forgot the tire one day and just used a tree that had fallen down.
Now the tire is in the trunk of my car, along with the sledgehammer. That way, if traffic pisses me off enough, I won't kill another human being. Instead, I'll just pull over to the side of the road and whoop up on a tire.