Dahon Launch D8 as checked baggage?

Hi, my wife and I own a couple of Launch D8 bikes, we're keen to take them on an international flight to do some light touring in China. The dimensions of the bikes folded up exceed the size limit of 158cm (they're 183cm folded). Has anyone had any experience breaking down these bikes further and checking on as baggage? I'm not super tool-handy but have basic skills, is this something that's going to be realistic to do or do I just have to suck it up and pay the oversize charge? Thanks for your time.