document: Both men will contest the opening Superbike and Senior TT races on the SG5 Norton machine.
  Donald, a two-time winner who has represented the team since 2014, said Norton have made a "huge amount of progress in that time".
  Fellow countryman Johnson, who made his TT debut in 2010 winning the Newcomers Trophy, is a rising star of the sport.
  The Adelaide racer said: "It is going to be an incredible experience riding a Norton around the Isle of Man Mountain Course, and with Cameron Donald as my team-mate is a massive honour.
  "I'm really stoked and will give it my best shot."
  Stuart Garner, chief executive of Norton Motorcycles, added: "We've made incredible progress since taking Norton back to the TT.
  "This was always going to be a long-term project and we're definitely on the next stage of our evolution. Running a two-man team will give us the best opportunity to move things forward."
summary: Norton have signed the Australian duo of Cameron Donald and David Johnson for the 2016 Isle of Man TT races.