Spend some time googling and reading about available rear and front motorcycle carrying options. I have carried my 188 lb Honda Trail 90 on a rear aluminum hitch rack safely with ratchet straps and bungee cords. This arrangement blocks access to rear cargo door, however. The weight of a motorcycle may shift the balance of your rig adding weight to the rear and making the front end light on it's front wheels.
It may be that a small trailer is best and also useful for carrying other gear that won't fit well inside your short rig.
