A lap in two months! You'll be doing nothing but riding. We went as follows:

Brisbane-Sydney-Adelaide-Perth-Broome-Darwin-Alice Springs-Uluru-Coober Pedy-Birdsville-Normanton-Cairns-Brisbane-Melbourne-Tasmania-Brisbane. Obviously this is just key points - there were lots of national parks, small towns, etc., etc. This took us 9 months, and we had already spent most of a month in Queensland.

We planned the trip around the following:

- the Red Centre in winter (too hot in summer, and some areas are closed for this reason)
- Victoria and Tasmania in Summer (cold and less pleasant in winter)
- Adelaide and Perth in autumn (not too hot, not too cold, although we did run into a polar cold front)
- Pilbara, Kimberley, Kakadu NOT in "the wet" (although we'd like to return to experience the wildlife in wet season some time).
- Northern Queensland NOT in "the wet" either.

So, we ended up as follows:

We arrived in Brisbane at the beginning of March. Left Brisbane at the end of March; to Sydney then west into Outback NSW, then SA, Kangaroo Island, and to Adelaide in April ; SA and then Nullarbor to Southern WA and Perth in May; north to Kalbarri, Ningaloo, Karijini, Broome, Gibb River Road in June;
Darwin, Kakadu in July; Alice Springs, King's Canyon, Uluru, Coober Pedy, Simpson Desert, Birdsville, Normanton in August; then through Northern Queensland to Daintree, Cairns, Great Barrier Reef, and Carnarvon Gorge in September; then back to Brisbane (so a lap in 7 months or so), then to Sydney, Thredbo, Melbourne, Great Ocean Road in October; then Tasmania, Canberra, and back to Brisbane in November. We left Australia in mid-December.

This worked well in terms of putting us in the north when it was cooler and drier, in the centre in mid-winter, and in the south when it was warmest.

PS - anti-clockwise is shorter.