Picture a bike where the central A-frame is actually a giant lockable carabiner.

The bike would be structurally unsound (possibly with a hinge) when the lock is open, so as to be unrideable unless closed.

When locked to something the bike would be impossible to steal without breaking it.
-- mitxela, Apr 19 2010

Freelock Locking Bike Frame http://inventorspot...ng_bike_frame_28203
This has been kicking around for a while. There must be a reason no-one has put it into production... [pocmloc, Apr 19 2010]

U-Lock built into frame http://blogtown.por...ted-for-the-weekend
Uses the frame in place of the bottom straight bar of the U-Lock. Not the same as mitxela's idea though. [swimswim, Apr 19 2010]

Yerka Unstealable Bike https://laughingsqu...ilt-into-its-frame/
Down tube splits in two and halves bend sideways; removed seatpost connects the two around a fixed object [notexactly, Nov 07 2018]

Lock. Bicycle https://www.trendhu...trends/lock-bicycle
Most similar to this idea that I've found yet: Top tube has a hinged section to go around a fixed object [notexactly, Nov 07 2018]

Saddle Lock Bicycle https://bikerumor.c...-protect-your-bike/
Seatpost hinges backward and saddle locks onto back wheel, optionally enclosing a fixed object [notexactly, Nov 07 2018]

BluLocks https://www.indiego...n-integrated-lock#/
Not very similar: Chain lock whose mechanism is integrated into the bike frame and also blocks pedaling [notexactly, Nov 07 2018]

Frameblock https://road.cc/con...E2%80%99s-part-bike
Cruiser-style frame where a couple of the tubes are replaced with lock cable that bends around to lock around a fixed object and/or the rear wheel [notexactly, Nov 07 2018]

self-locking bike [notexactly, Nov 07 2018]

I don't think that's quite the same though - for one, it's nothing like a normal bike, and two, it clearly doesn't need the lock intact in order to ride because it can fold 90 degrees anyway.

This one could be made from a normal bike frame, just by cutting through the two main beams, welding a hinge in place on the lower one, and locking part to the other.
-- mitxela, Apr 19 2010


[+] But, I am guessing that the reason this doesn't already exist is because of how it would affect the strength of the frame. Unless it locks together very tightly, it would result in wiggling of the frame when the bike takes impacts. Over time, that might cause the frame to wear down and break more quickly than a non-hinge frame. Still, there are in existence frames that fold and incorporate hinges into the frames. See my link for a non-hinge cousin of this idea.
-- swimswim, Apr 19 2010


Also, you would still need something U-Lock-like with which to secure the wheels.
-- swimswim, Apr 19 2010


Adds weight to the bike, reduces the frame stiffness, weakens the frame, more likely to fail catastrophically in a crash, doesn't secure either of the wheels, and renders the entire bike unusable if you lose the key - but otherwise a great idea.
-- hippo, Nov 07 2018



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