Hard to find in Oz, and still expensive compared to other countries.
I do agree with the Mobil1 0w40 idea and Thinken's train of thought, however in Oz it's not an option as far as I'm concerned.
I use
Elf 10W50 which you can get from your local Elf-Total distributor. Have a look at the Elf Oz website for one in your area.
I know this is debatable but in my opinion Elf (or Total= the same) is one of the best oils available.
They don't do the big hooha thing but a lot of people use them for racing despite having different stickers on the bike.
This oil works extremely well for the hot conditions we have in Oz.
Go and have a talk to your local distributor ( I won't mention the price on here but you'll be very happily surprised) I'll buy this in 20l containers and it's well priced and VERY good.
The oil comes out clean after 5 Hrs and testing has proven if I leave it in longer due to the riding schedule it holds up very well.
I have been using this stuff for ages in different bikes and this oil performed exceptionally well even compared to big know brands.
I know, like tyres, oil is a personal preference. All I can say I never had to fix any of my bikes due to premature wear, lubrication issues, bad shifting gearboxes, slipping clutches, running hot or any of the oil related issues.
The 501 has 60 hours on it and the oil comes out clean and never had a spanner on it except for service.