Regular unleaded fuel in Japan is a minimum 95 RON. The Australian Jazz is made in Japan not Thailand or mainland China (like the future European Jazzes) and hence designed from the ground up for at least 95 RON fuel.

In fact Australia was one of the only countries outside Japan to get the VTEC Jazz at launch. Due the the small size of the Australian market and the the very special relationship Honda Japan has with Australia we often get some good things like the batch of real Type R Integras at the end of life of the last model. Australia is used for product testing due to the space and harsh and varied climate. I remember watching a promotional video at one of the large Honda bike factories (bigger than 400ccs) in Japan and realising that the scenery was Australian gum trees.