With us it's always what we shouldn't have taken. Keep the spare clothing to a minimum. Don't double up on tools. Make sure you have stretchy straps, like occy straps - but only one or two. A good quality handlebar bag is always worthwhile. See if the tour operator supplies one. Suntan lotion is cheap in Australia, but make sure its in the checkin luggage.
Many thanks! I'm also told a money belt is good, and a bike lock!
Off on Saturday.