What if instead of carrying around a hand-held bike lock, your bike was its own lock? That’s the premise behind the Yerka Project, an attempt to design an “unstealable” bicycle.

Image from the Yerka Project.

The ingenious design works like this: The bike frame’s down tube splits into two pieces, each of which then twists so it’s perpendicular to the rest of the frame. Once the two pieces are turned 90 degrees, the bike seat pulls out of its tube, and slides into the down tube pieces, like a giant lock.

Thus, the frame of the bike becomes its own lock. The only way for a thief to break the lock is to break the entire bike.

There is a weakness, though: Individual components of the bike are still vulnerable. It’s only the frame itself that’s unstealable.

So far the designers have only produced a prototype, but the concept is straightforward enough that it could easily find its way to an assembly line. There are fewer moving parts than on a folding bike.

Still unsure how it works? Watch this example video:

 Cross-posted at Greater Greater Washington.