Burt Munro, an elderly and eccentric New Zealander, spends years meticulously restoring a 1920 Indian Scout motorcycle. His dream is to take it to the Bonneville Salt Flats in Utah to see how fast it can go. Despite his limited resources and declining health, Burt's determination and passion drive him to pursue his goal. He scrimps and saves, overcomes numerous obstacles, and endures the skepticism of those around him to make the long and difficult journey to the United States.

Upon arriving in America, Burt faces a new set of challenges, including cultural differences and bureaucratic red tape. However, his infectious enthusiasm and genuine spirit win over various strangers who help him along his path. Burt's unwavering commitment to his dream and his unyielding positive attitude lead him through a series of adventures and misadventures as he strives to test his beloved Indian Scout on the famed Salt Flats, pushing both himself and his bike to their limits.