I don't have a tow hitch on my X5, but on my cars that do, I use a Yakima HitchFork. It is now old, and discontinued, but still awesome. It folds up/down and basically gives you a pair of Yakima round 1" bars to mount to. So you can use the exact same rack mounts on the hitch rack as you do on the round bars up top (if you have those ... I actually have aero-shaped Rola bars on my X5).

The interchangeability (e.g., moving mounts from the hitch rack to the roof rack as needed) was the main reason I went with the HitchFork solution. With a family and biking friends, I needed all the flexibility I could find.

So the HitchFork would allow you to mount fork-mounts, wheel mounts, whatever you want, as long as it would fit on a 1" Yakima bar. I don't know why they discontinued it.

Another reason for a hitch-rack - you might want a rocket box up top, especially with the limited interior space in the X5.

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2001 X5 3.0i, 203k miles, AT, owned since 2014