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I'm currently trying to unlock my bike that has been sitting on my porch for a while, the key works and turns, and I can hear the lock engaging/disengaging, however I cannot get the shackle to come out. I think their might be dust/sand stuck in the mechanism however I'm not sure how to get it off now to check.

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I've read about this problem in reviews of OnGuard locks on Amazon, so it's likely a design flaw with rust as a possible culprit. I haven't read about any solutions to it, beyond renting a power grinder to cut the lock off so you can buy a better one next time. That was one of the reasons I chose not to buy OnGuard, the other reason is one key fron an OnGuard lock fits multiple locks, which would allow a bike thief to walk around with a large key ring trying several keys until one of them works (the cheaper Kryptonite locks also have this problem). – Robin Ashe Jul 3 '12 at 22:25
I'd try first putting it in what you believe to be the unlocked position, then applying a hammer in such a way as to knock the pieces apart. Failing that, an angle grinder. (If there's a Harbor Freight nearby you can probably buy one for under $20.) – Daniel R Hicks Jul 4 '12 at 1:28
Related: U-lock stuck on a bike – Neil Fein Jul 4 '12 at 3:57

Get some "Creep" or other penetrating oil (ask at Home Depot or Lowes and they'll point you right to it). This is similar to WD-40 but it foams a bit and seeps in everywhere. Apply liberally both at both ends where the U plugs into the bar as well as where the key fits in (key may turn without the tumblers moving completely).

This will likely loosen things up...a bit of patience and a bit of trying to move the parts around will usually work wonders.

If this fails, apply some more "creep" and use a persuader (hammer, etc).

If that fails, you're going to need a hacksaw and a couple of blades.

Good luck! Note: This is karma's way of telling you that your bike likes to live indoors when it's not being ridden :-)

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The lubricant to use is Tri-Flow Teflon-bearing spray lube. – Daniel R Hicks Jul 4 '12 at 4:20
I like teflon for once parts are moving, but to get into the rusted up crevices, creep is the stuff. or… both will do a lot to get things unstuck. – Ken Hiatt Jul 4 '12 at 4:46

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