Help me unjam my U lock

November 6, 2015 2:09 PM

My Palmy U lock, with one of those simple circular keys, is stuck. How do I open it?

Here's a picture of the mechanism where the key goes in. I think the key is entering turned in the unlocked direction, and then I can't turn the key or open the lock.

Is there something I can poke/move, and then open it with a key? Should I try to pick the lock with a pen or something?

Thanks in advance!

posted by domnit to Grab Bag (11 answers total)

Response by poster: To clarify, the picture shows the lock in its current jammed state. I'm not sure what it's supposed to look like, but hoping someone here knows how these types of locks work and are supposed to look.
posted by domnit at 2:10 PM on November 6, 2015

So the key can go in but won't turn?

When this has happened to me, bike repair people have told me to add a drop of chain lubricant to and let it sort of settle in around the mechanism, then try turning. I have fixed two of my own Ulocks this way and one belonging to a friend. I suspect that WD-40 would work if you don't have anything else.
posted by Frowner at 2:16 PM on November 6, 2015

Response by poster: Right, key goes in but doesn't turn. I think I took the key out hastily. The lock is fairly new and hasn't been rained on, so I don't think it's just worn away lube.
posted by domnit at 2:30 PM on November 6, 2015

Is it locked around the bike? If not, just throw it out and get a new lock (or see if they'll replace it under warranty, but I personally wouldn't trust the same design if the first one jammed on me while it was still fairly new.)
posted by contraption at 2:35 PM on November 6, 2015 [1 favorite]

I had a jammed lock. I used chain lube and that sorted it out beautifully. From my research, it said WD40 is NOT a good thing to put in locks because it's not actually a lube and can cause the lock to seize up again.
posted by EndsOfInvention at 2:35 PM on November 6, 2015

Also, if the lock is currently on the bike, I would not plan to reuse it once you do get it off. Locks that might jam closed without warning are almost as bad as locks that can be opened with a Bic pen.
posted by contraption at 2:38 PM on November 6, 2015

Sorry to keep chiming in, this is my last comment: it looks like that lock is solid aluminum, so a big set of bolt cutters or a hacksaw should make very short work of it. From the Amazon reviews it looks like the jamming problem is pretty common.
posted by contraption at 2:44 PM on November 6, 2015

Response by poster: Fair point that this could happen again in a less convenient/safe place than work. A security guard helped poke at it with me for a few minutes but ultimately chopped it off my bike. It was fun while it lasted, Palmy lock, but I won't be getting another.
posted by domnit at 3:20 PM on November 6, 2015

Glad your problem is solved, but looking at the picture, one of the pins is suspiciously well-centered in the keyway slot in the outer ring, and seems almost to be sticking up into it.

If it is, that could jam your lock. Normally the presence of your key would keep pins out of that keyway, and most such locks are designed so that you can only insert or remove the key when the two slots are lined up.
posted by jamjam at 3:29 PM on November 6, 2015

Response by poster: Thanks jamjam. We tried twisting the slotted ring things to line up the slots, but they were just getting bent instead of moving. Which is where lube probably would have helped, but I was just anxious to get my bike back.
posted by domnit at 3:43 PM on November 6, 2015

Just supporting the caution about WD-40. It lubricates initially, and can free up frozen mechanisms, but after a while the light oils in it evaporate, and what's left is a gummy residue. If it's all you've got, use it, but wash it out later with alcohol or kerosene. Penetrating oil is better, or something with graphite in it, like Lock-Eze.
posted by Kirth Gerson at 4:36 PM on November 6, 2015 [1 favorite]