Claiming a win in a game that hasn't started

This has probably been asked before but

Is it possible to claim a win if the opponent has left the site in

a) a clan game
b) a tournament games

The reason I am asking is that the time doesn't seem to start ticking ...

Thanks
TSP

Edit: The games in question are when I am playing black and white has not made a single move

The time should start ticking. I've not played move 1 in games as white recently until the timebank has begun to be used.