You can just use a small grinder or a dremel tool to grind off two connecting pins flush with the surface and drive them out with a small punch, I works for all sizes no special tool needed .
Yeah I just ordered a motorcycle chain breaker from a local shop yesterday for the same purposes. I figure athough I don't need to cut the big chains too often, when I need to it'll sure come in handy. My bike tool can't handle it and I'm not gonna grind on my tool or a chain if I can avoid it. Not that it's a bad idea for something to do in a pinch..