The attack goes on for as long as five minutes with the teens returning repeatedly to hit the victim with metal bars ripped from his own wheelchair.
The suspects, 16 and 15 years old, were denied bail and both are facing charges including robbery and inflicting grievous bodily harm.
The victim, a 35-year-old Canadian tourist, is in stable condition after undergoing surgery for severe lacerations to his head and a skull fracture. He was in Australia to visit his girlfriend.
AP contributed to this report.