1st I dont know what a class 1 lic is and Ive been in the transportation industry and licensed to drive ANYTHING for over 20 years. I have a class A commercial with all endorsment except hazmat. 2nd DOT laws dont apply to recreational vehicles used for personal recreational use. Now if you are a RV puller and try to pull two trailers then you best be properly permited. What you are asking about is perfectly legal to do and is done on a regular basis. DOT cops don't ever look twice at RVs. You can drive as big an RV as you can afford pulling as many ATVs as you can, with no med card, no large vehicle driving test, no eye or hearing test, and there is not a DOT out there that could care less, except in Calif, all bets are off when you cross that line!