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When George Miller was developing the movie, the film wasn't going to be a science fiction film set in a dystopic future and originally the character of Max Rockatansky wasn't a policeman who succumbs to madness when he loses his family and that Max was a journalist who becomes a shell of a man who goes from one place to another witnessing horrific accidents.
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.