As others have mentioned, force it like any other key in a lock and it will snap. The barrel has anti-drill plates inside and the can slip out of alignment, but as dubcat has mentioned you jiggle the key to re-align the plates. I've sold over 100 Roadlok's and I've had two keys snap in 3 years. On was due to a seized barrel through lack of general maintenance the other was due to the key not being inserted correctly and then forced. The barrel is exposed to the elements as are other moving parts on a bike. If you don't maintain the "parts" they will fail.
I have two roadloks and can't help thinking that the newer one is lower quality - whenever I go for a decent ride the key slips into older one with no problem but on the newer one I usually have to use a toothpick or similar to get the lock internals to line up before I can get the key in; fortunately this is only likely to be a problem before I lock the pin in place. edit - neither has had any 'maintenance' or lubrication and both are subjected to the same cleaning processes (soap and water). I should also add that neither roadlok was bought via this forum so I'm not passing any comment on the ones that are being sold here.
