Originally Posted by alanbikehouston

The 2005 locks from both OnGuard and Kryptonite with flat keys use rotating plates inside the key way. As the red warning sticker that is on the locks says, you MUST insert the key fully before you begin to turn the key.

What the stickers don't tell you is why. If you turn the key before it passes the last of three, four, or five rotating plates (depending on the lock model) you rotate the plates out of alignment and "freeze" the lock. This is INTENTIONAL as it makes it more difficult to pick the locks. People did not want "round keys" because of their fear of the (absolutely imaginary) risk that someone would pick their lock. So, a "pick resistant" design is replacing the round key design.

The locks can still easily be opened by realigning the plates. Aligning the plates takes about ten seconds after you have practiced the technique for a few minutes. It takes FAR longer to describe the alignment process than it takes to carry it out.

Turn the lock so that you can see down into the key way. You will see an opening for the key. When all of the plates are perfectly aligned, that opening forms a smooth sided rectangle that extends to the bottom of the crossbar. If any of the middle plates are out of alignment, the keyway has jagged sides. If the bottom plate is out of alignment, the keyway does not extend to the bottom of the crossbar.

Just take the tip of your key, and insert it 1/16th of an inch into the key way. Gently turn the top plate until its key way is perfectly aligned with the second plate. Then, insert the key 2/16th of an inch into the key way and align the second plate with the third plate. Go deeper to align the third plate with the fourth, and the fourth with the fifth. When you are finished, the keyway goes smoothly to the bottom of the crossbar.

When the alignment is correct, you gently wiggle the key down until you reach the bottom of the crossbar. The key will turn easily and smoothly, and the lock will open. If there is ANY resistance, do NOT force the key. Resistance means you missed a plate and must realign the keyway.

I now own about ten of the new flat key locks. Two of them "froze up" when I failed to fully insert the key before turning it. After I learned how to align the plates, the realignment process takes ten seconds or less. But, now that I understand the new mechanism, I NEVER have a lock jam up. I've learned to work the key down all the way to the bottom before lightly turning it. This becomes an automatic process that you do without giving it any thought.

Frankly, I LIKED the round key design. Easy to use. Never jammed. There is not a single documented, proven case of a bike being stolen because the lock was picked with a BIC pen. But, because of the BIC pen uproar, we now must learn how to use the new flat key locks. After new owners learn the quirks of the flat key locks, they are easy to use, and have the benefit of being the most theft-resistent design in the history of cycling.