Every second a bike is stolen. The three engineering students from Chile behind this project have all been victims. That's why they came up with Yerka, a bike that cannot be stolen.
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The innovation here is simple: the frame of the bicycle becomes the lock. A detachable seat, a unique hinge and lock mechanism lets the rider secure the bike just about anywhere. No need to lug around those monstrous U-locks.
If someone wants to steal the bike, he or she will have to break the lock, thereby breaking the bike. Hopefully a potential thief is smart enough to put two and two together to figure that out.
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As Kristen Lofgren points out on Inhabitat, a thief could steal the tires and saddle, but those are cheaper to replace than an entire bike.
See the video.