There are been a number of posts from folks having similar problems with the new "flat key" locks from OnGuard and Kryptonite. I thought those "complaints" involved people who just were unfamilar with a new lock, or who had gotten a rare "defective" lock. Or, as Raiyn claims, maybe anyone who has trouble with a flat key lock is just "stupid".

My opinion changed when I put a "new" 2005 "flat key" lock on a bike today. It locked up smoothly. But, when I tried to unlock it, the key would not seat into the keyway. I could move the the key back and forth, but I could not open the lock.

Looking inside the keyway, I discovered the problem. The "flat" key inserts into a keyway that ranges from 5/8th inch deep to one inch deep (depending on the model and the thickness of the crossbar). That keyway is built with seven to ten thin metal plates layered in a stack. Each plates has a rectangular channel to hold the key. The top plate has two "channels" in its rectangular that engage with the two grooves on the sides of the flat key.

But, the top plates in the stack can turn independently of the other plates. If you insert the key and begin to turn it before the key has reached the bottom of the keyway, it may turn easily, but will not engage the bolts. Although the key moves, you can not lock or unlock the crossbar.

In my case, I was bending over the lock at an awkward angle, and I must have twisted my wrist just as I was pulled the key out of the lock. When I reinserted the key to unlock the bike, the key turned, but I could not unlock the bike.

So, what do some owners do when their lock refuses to open? They force the key deeper and forcibly turn the key. However, when key is "trapped" against the misaligned plates, the key will break. And, the reports of owners breaking the new "flat keys" are numerous.

Fixing a non-working flat key lock: shine a light into the keyway (some Kryptonite and OnGuard locks supply a lighted key). Insert the key 1/8th inch and align plate one with plate two, so they form a single rectangle. Then insert the key 2/8th of an inch and align the top two plates with plate three.

When every plate has been realigned with the one above it and below it, you will be able see a deep rectangle going down to the center of the crossbar. You can now put your key down deep enough into the keyway to engage the bottom plate and open the lock.

This "quirk" exists on EVERY model of the 2005 flat key Kryptonites and 2005 OnGuard locks. The designs of their keyways are very similar.

And, a bumpy road might misalign a plate, so be prepared. If you have a lighted key, keep it with you. If the key will not fully seat, or the key turns, and the lock does not open, take your time, and realign the plates one by one. Then your lock will open.

I'm beginning to miss my round key locks...

Meh!

Sometimes you wonder if the people selling their junk actually test it first or just say hey here we built this thing - buy it and test it for us!

Frankly, I don't see "You must insert key fully before turning" as a design flaw... Would you expect to be able to open any other lock by inserting only 1/3 to 1/2 of your key?

No, but if...


then I would consider that a design flaw.

If you insert a key 1/3 way into the lock of your front door, it obviously wouldn't work. But I would be shopping for a new lock quickly if a small error disabled the lock all together. Or caused me to carry around a lighted key to make adjustments "just in case".

With every other key I have used in the past fifty years, if the key is not properly seated, it will not turn at all. The "new" locks are the first I have seen where the key will turn easily at a variety of insertions depths, and the first locks I have ever seen where merely turning the key can disable the lock.

The OnGuard lock I bought last week has a tiny red warning sticker slapped on next to the keyway warning in microscopic lettering that "the key must be fully inserted before turning". That sticker suggests to me that OnGuard is aware of the problem. It can be difficult to "feel" when the key is "fully inserted", especially if a misaligned plate is "caught" on the key. A "warning sticker" is not a "cure" for the problem.

I "experimented" with five or six flat key locks today. On some of them, the plates fit tightly together, and just "jostling" the lock on a bumpy road is unlikely to put the plates out of alignment. However, on the "flat key" lock that jammed today, the top plate is very loose, and it is not a lock I can trust for use "on the road".

I can agree with the idea that if a bumpy road can cause the issue, that's a flaw. I've read the threads on the onguard locks - but I've also USED an onguard lock for more than a year, and in my opinion a little bit of care solves the problem... If security is improved by a design that requires me to be a little less careless, that's a tradeoff I'm willing to make.

Haven't used my new Kryptos yet, of course... with my luck, I'll probably be back complaining of broken-off keys immediately after I first try them! ;)

I've only had one time where my lock acted up from this symptom (onguard ultimate), and it was when i was mudging with it trying to get it to do this.

I also found that this "problem" makes the lock far harder to mess with from a lockpicker's perspective....this could mean popsicle sticks may not be our bane for some time.

However, all disc lock cylinders are like this. My bike chain's padlock has a disc lock like this as well.

best tip: graphite lube your lock, and keep it lubed. Also insert your key slowly, and learn where it's full insertion point is. It may help to mark the key for that point.

I've had this feature on my fahgaddaboudit lock forever and it's never bothered me. I just keep turning it back and forth till it seats all the way in then it opens.

I use a NY3000 ULock and minilock daily and have no problem correctly operating either lock. I figured out the first day I had one of these locks that you have to insert the key all the way or it won't work. It's no problem aligning the disks with the key.

Yea, I was afraid for about 4 seconds that I might've messed up my fahgettaboudit but it fixed really easily. I accidentally pulled the key out as I was turning it so about 2 of the disks on the very bottom weren't lined up. All I had to do was turn the key a little as I put it in to get into the bottom disks.

The only "problem" I have is after a while the U part started to rust a little and I have to yank kinda hard to get it out. All I need to fix it is a little oil, then it's smooth as butter.

I'm under the impression that Koffee owned a pair of the previous-generation New York Locks (i.e. the round key versions). Her first message in your Best Bike Locks - 2005 Tests thread seems to confirm that.

Anyway, I've also owned two of the old-style New York Locks. One malfunctioned much like Koffee's locks did and was replaced by my LBS, while the other worked problem-free for eleven years before I sent it back to Krypto under the replacement program.

This is odd. I own three flat key Abus locks and I haven't had a single problem. I use one or the other on a daily basis. I just have to make sure that the key is in all the way before I turn it for the lock to lock. How do Abuses differ from the Kryptonites and On-Guards?