Motorccle Carrier on Stock Hitch
 

I have an E53 3.0 (manual) with the stock hitch. My understanding is that the stock hitch is rated for 6000lbs and generally tongue load is 10-15% of that so 600-900lbs. I have a 600lb motorcycle I'd really like to be able to put on one of those hitch mounted carriers to move it about 3 hours on the highway. I don't intend to do this more than maybe once or twice a year but I would like to move a 200lb dirtbike in this manner fairly regularly. Has anyone done this with the e53?

My (longwinded) concern is that while this sounds fine on paper, you get significant moments about the longitudinal axis of the trailer hitch receiver. With a normal trailer hitch you don't get loads like this as the arm is relatively short from the center point of the ball to the receiver. Tall trucks sometimes do when you use a drop down) receiver. For the motorcycle carrier, the arm will be from the CG of the motorcycle to the longitudinal axis of the receiver. Slop in the receiver will mean that the motorcycle will rock about the longitudinal axis and cause considerable inertial loads about the CG), more so from the deceleration caused by the impact when the receiver takes up that axial slop.

I personally would never trust those hitch mounted carriers with a 600 lb bike. The dirtbike should be no problem. My understanding is that the stock hitch has a tongue load limit of around 330 lbs and thats the most I'd want sitting on the perch.

For the 600 lb bike, I'd definitely grab a uhaul rental and strap it down.