I rode a bicycle across the U.S. and I too thought I could just pitch my tent on the side of the road...WRONG. You really have to go OFF the road, usually in a grove of trees, down trails, back yards of abandoned houses and abandoned gas stations, Honor system camp grounds (Contact me and I'll tell you a little trick I used to keep from paying!), and the little parks that every small town in Kansas seems to have; just let the local law-dog know what you're about. In Colorado and Utah there is a LOT of BLM and wildlife management land were you are allowed to camp for FREE.

Of course, I was on a bicycle, not a motor bike. Being silent worked to my advantage, I'm sure.