I have the OEM hitch, so it would have been easy to buy a hitch-mounted rack, but I just don't like them. The bikes get dirty, and they also move around and get marked up, in my experience. Maybe they are better than they used to be. There are new and more elaborate hitch mounted bike carriers, including swing-away models so you can get to the load area.

I had a Thule roof rack with three upright carriers set up for a previous car (long gone) so I just bought new (longer) Thule crossbars with the attachments for the BMW X5 rails. I mounted the old upright bike racks on the rails. Works great. Two considerations: It helps to be tall (I am 6'4", so loading them isn't a problem) and you have to remember not to back into the garage with the bikes on.

The Thule web site lets you build the setup you need. Lots of photos. You can also use the same load bars to mount ski racks, board racks, and luggage carriers (although moving the attachments back and forth is a drag).

If you get the Thule, you need LB58 load bars, 450 Crossroad railing feet, and a 596 six pack lock set. Various upright bike holders are available, front wheel on or off. For a mountain bike you likely need the larger jaw due to the size of the bike downtube.

Jeff

__________________
2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue