Open cylinder bike lock in 30 seconds

The type of bike lock that has a combination of 4 numbers and is a cylinder can literally be opened in 30 seconds. I'm sure you if you don't know the combination already, it might take a little longer. However, with this method you'll see how easily the bike lock can be cracked. This is educational, however, it should also educate you not how to open this bike lock but it should educate you in the fact that you now know you need to find a new bike lock!