I can speak from personal experience. I pull a 31' fiver with a 10' motorcycle trailer behind it. Of course it must be a frame mounted hitch... That goes without saying. Illinois is legal. Mostly east coast states have heartburn. West coast states may have issues. Call each state. I have the proper Michigan endorsement. We put 12,000 miles on this train last winter. I DID get a ticket in Florida, and paid a $110 bond. Ticket was not adjudicated, meaning they got my bond money, but no points were assessed. It is normally a three point violation , which I protested by mail. Be careful, plan your fuel stops, plan your turns, and make sure all your brakes are in good shape. Have fun and maybe we will see you on the road!