I haul two bikes in my toyhauler, one for me and one for the wife. When you come back from a days ride and load both bikes you WILL most certainly smell the hot bikes unless you have a door separating the garage from the rest of the unit. There is a reason for those two vents which provide cross ventilation for the garage. A wall and door seperating the garage is a good idea also when you have guests sleeping in the garage or you want the ramp down when one of you wants to enjoy the view and the fresh air while the other one wants to take a quiet nap.