supported, or on your own
There have been a few companies that ran fully supported bike tours to the outback.
ROC, “Remote Outback Cycling” was terrific with, for example, a 45 day Townsville to Broome via the Savannah Way; Gulf to Gulf, cross country from Port Augusta to the Gulf of Carpentaria via the Birdsville Track; and plenty of shorter trips.
Sadly all history now. You are on your own.