If you have ever locked up your bike, you were most likely using a type of security called a tubular lock. Tubular locks, unlike most other locks, require a special circular key to open. If this key is lost, getting the lock to open can be difficult. You may be able to open the lock with a specific type of lock pick, however. This is called a seven-pin lock pick. The lock pick works by mimicking the movements of the lock's key to release it.
Twist the seven-pin pick's tightening bolt to the left, loosening it. This allows the pin keys to slide down into the proper position for picking the lock. Press the tip of the pick gently against a solid, flat surface.
Turn the tightening bolt to the right. Ensure that the pin keys are still able to move before trying to pick the lock. Line up the pick's pin with the notch on the tubular lock. Insert the pick into the lock.
Rotate the pick to the right as you insert it. When the pick reaches the back of the tubular lock, it presses against a spring. Continue pushing to the right, and the lock opens.