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For the lead role, George Miller had considered an American actor to "get the film seen as widely as possible" and even travelled to Los Angeles, but eventually opted to not do so as "the whole budget would be taken up by a so-called American name." So instead the cast would deliberately feature lesser known actors, so they did not carry past associations with them.
Most of the extras used in the film were paid in beer.
The "get-out-of-jail-free card" that Goose gives the triker was an on-set joke. Because of the limited budget, the biker gang was an actual biker gang (the Vigilantes), and they had to ride to the set each day in-costume; often with their prop weapons displayed. Since the production company expected them to be pulled over by the local police, each was given a letter explaining the film's peculiar requirements, and asking for law-enforcement's understanding and cooperation.
Tim Burns (Johnny the Boy) was so into character that he annoyed everyone on-set, and was abandoned one day during lunch while handcuffed to the wreck.
Some of the things Nightrider yells over the radio are lyrics from the AC/DC songs "Rocker" and "Live Wire."
James McCausland: The bearded man wearing an apron in front of the roadside diner watching the police cyclists and tow trucks drive away is the film's co-writer.