around here if they are abandoned which only happens if they are parted, they are fair game. Like say a wheel or wheels are stolen, the owner abandons the bike, thusly in two weeks, rarely longer, theres nothing left but a frame. Thats only if it isn't ulocked.

I talked to a guy who at the time left his bike near his job and coulnt get it, his wheels and seat were stolen so he said eff it and left it for the scavengers.