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Revealed: The secret technique used to steal bicycles

This technique has been known for decades. Enterprising thieves when I was an undergrad in the 1970's used to carry a thermos with liquid nitrogen. A little of that, and any lock is as brittle as glass. The only defense was to put your good bike in your dorm room (in violation of the regulations), leaving only the junkers outside.

In the video, the lock is on a hard, flat surface, making hitting it simple as almost all energy is transferred to the lock. In practice, when attached to a bicycle, there is no consistent hard surface to hit against. Also, this makes a lot of noise, which thieves definitely do not want.

Just hold one hammer beneath the frozen parts and whack the top of it with the other hammer. This guarantees you a good strike.

Although some bike riders might consider it a horror, maybe it is time to build in the lock to the bike. If it were in the steering column and locked the wheel at a slight turn angle, it would be better protected. Or in the front hub? That can't be beaten on without ruining the hub.

I know the big bike people are way into weight. Keep in mind that I have no idea how much a bike weighs, but:
Bike 1 advertisement:
Our bike is 10 lbs! Lightest bike on the market! (but you have to carry a 3 lb. lock)
Bike 2 ad:
Our bike has a lock built in! (but it weighs 13 lbs)

I would just pick up the bike, put it in the back of my truck and drive off if the wheels were locked...

I think when the technique is over 20 years old it can no loner be considered a secret of any kind.

Guys, doesn't the lock also fail under the careful minitrations of an arc welder? If nobody notices you hammering like a fiend on a bike lock in the middle of the day, you can liberate an entire rack with a welder or small gas torch in about the same time it takes to pound one out.

Using a hammer is for troglodytes. A competent lock cracker freezes the lock and then uses a "nut-splitter" or similar high pressure/mechanical advantage tool to shatter the lock cylinder nearly noiselessly - except for the pop when it shatters. Which can be padded around to reduce even that sound. A good nut-splitter can generate 100K+psi. Some locks don't even have to be frozen.

Any external lock can be defeated. I could easily cut that particular lock off in a second with a bolt cutter without damaging the bike, A better lock would be integrated into the frame. Breaking an integrated lock would break the bike, making it useless.
It is best to think of locks as devices that keep "honest people honest". Some people would break an expensive bike just for fun or to steal parts.
Once, a person cut a "club" from the steering wheel of a car and hotwired it and parked it across the street with a note that said "the club ain't worth *hit" just to prove a point.
Some expensive locks cost more than a used bike or cheap new one. Think about it before purchasing.

A mechanical device designed to keep friends out of your stuff.

As other folks have said: old news. Internet videos shown how to open u-locks with cylindrical lock mechanisms in 5 minutes with a pen barrel. Frame and fork locks don't prevent the bike from being picked up and carried away. Thick braided cables, with high-quality solid-body padlocks are probably the best, but no lock will stop a determined, professional thief. To paraphrase Sun Tzu, keep your friends close, but your bicycle closer!