I dont know why not, if a model airplane was flown across the Atlantic, a bike ought to go from MN to AZ. Now all the theoretical stuff out of the way, to be really sucessful, it would almost have to be based(in my opinion) on an industrial type 4 stroke. Like a 2.5hp Lifan or the 3.5hp Harbor Freight engine, or others. The configuration of the bike would have to be designed around comfort. I am just finishing a recumbent built for traveling, it suits me better in the comfort department. I also have a trailer to go with it. What it boils down to is you will need somewhat of a custom built bike. I think you would be hard pressed to buy a standard engine kit and bike and get very far, once again my opinion.