I thought it had to have 200w to be considered a vehicle. 50cc to be considered registerable and then taller than 90cm to the seat to be considered a motorcycle. From what I read my guess was that as long as you had a general driving license it was ok to ride them (private property), not necessarily a motorbike license. So now I'm a little confused.
I can't find the 50cc rule anywhere.
http://www.rta.nsw.gov.au/registrati...kes/index.html
There it says 90cm. Otherwise it's considered a mini bike or
http://www.rta.nsw.gov.au/usingroads/bicycle/index.html
motorised recreational device (200w)
I agree it looks like a motorcycle, but no way would I consider riding it on the freeway with real vehicles. The cop said he had trouble with those bikes in the area so they were probably cracking down on them.