Had exactly the same problem today. Only just seen this thread, JC summed up the problem. I assume the problem is from when the key is either removed after locking or when I tried to unlock
somewhere I once read it's best to apply oil to the the key and to lock and unlock a few times. They said that's the best way to oil a sticky lock. Spraying oil into the mechanism can caused it to clog up with dust and grime. Not sure if this also applies to bike locks.
Had exactly the same problem today. Only just seen this thread, JC summed up the problem. I assume the problem is from when the key is either removed after locking or when I tried to unlock
somewhere I once read it's best to apply oil to the the key and to lock and unlock a few times. They said that's the best way to oil a sticky lock. Spraying oil into the mechanism can caused it to clog up with dust and grime. Not sure if this also applies to bike locks.