Carrying a motorcycle without a trailer

Like this?

Not sure on Aussie design regs and standards and insurance if you made your own!

http://www.showmesome.info/hilux/workshop/rack.htm

I've seen em on buses and stuff - a lot of round australia tourists have the faithful combo of old bus and postie bike.

You'd get away maybe with a little postie bike or trail bike but not a full on road bike - too much weight to mount like a pushbike.

you ,might want to check the static weight your towbar can handle before you go ahead as well.
most bars are for pulling not for a weight above and behind the mounts.
just a thought?

Would something like this be suitable ? http://www.abiketow.com/