Originally Posted by Dirt Bringer
1upusa roof rack. By far and away the best wheel mounted bike rack, no contest. If you prefer fork mounted bike racks the Yakima Forklift can lock to the rails, as well as a Thule model I don't recall. However if you plan on going with a wheeled mount, don't even bother with anything else, the price difference between the Yakima and Thule racks to the 1upusa rack is so minimal that it's simply not worth the quality and design difference. Also, whatever you do, avoid the Yakima Frontloader. I've heard horror stories.
If you look into any wheel mounted roof rack, you'll find horror stories about all of them. Except the 1up actually. I haven't seen any about that one. I just can't get over the aesthetics. I'd say it is the most solid of the bike racks (quite literally too).
I've had no qualms with the Frontloader and I carry a downhill bike on a regular basis without concern that something catastrophic is going to happen. People tend to just be idiots the majority of the time, in my experience.