On his lock strategy page, Sheldon Brown (RIP) recommends locking a bike by securing the rear wheel inside the rear triangle with a U lock. A YouTube video shows Sheldon might be wrong!
I almost always use the “Sheldon Method” of bike security by wrapping a U lock around the rear wheel inside of the space between the seat stays and chain stays as shown below.
Even if a thief removes the rear wheel, the lock is inside the frame and the bike isn’t going anywhere.
Sheldon claimed that it’s too difficult to saw through the rim to make stealing the bike worthwhile for most thieves. “Cutting the rear rim is much harder than you might think,” he wrote. “Since the rim is under substantial compression due to the tension on the spokes, it would pinch a hacksaw blade tight as soon as it cut partway through. Then there are the wire beads of the tire, also difficult to cut.”
I’ve been wanting to do a Myth Busters style video to test Sheldon’s hypothesis, but I see now that somebody’s already demonstrated the ease of taking hacksaw to tire and wheel. If you can’t watch the video, it shows somebody ripping through the rear wheel in about 10 seconds with a hacksaw.