The motorcycle in cinema-Deathsport.

In the Year 3000, there will be no more Olympic Games, World Series, or Super Bowl. There will be only...DEATHSPORT!

Wiki:

"Deathsport is a 1978 sci-fi B-movie produced by Roger Corman about a post-apocalyptic world where criminals fight to the bloody death in the sporting event, Death Sport. The film stars David Carradine and Playboy Playmate Claudia Jennings.

One thousand years from tomorrow after the great Neutron wars, the world is divided into a barbaric collection of city states, surrounded by wastelands where only mutant cannibals and fiercely independent warriors known as Range Guides live. One of these city states, Helix, is planning war on another city state, Tritan, and to prove the superiority of their newest weapon, the "Death Machines" (essentially laser equipped Dirt bikes) they plan a special Death Sport. In the future, the death penalty was replaced by the Death Sport, where criminals battle each other to the bloody death for their freedom.

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But this time the mad Lord Zirpola (David McLean) is using the "Death Machines" and pitting them against some Range Guides he managed to capture. Foolishly, one of these guides, Kaz Oshay (Carradine), is the son of the greatest Range guide that ever lived. He forges a bond with a female guide Deneer (Jennings) and vows to escape with her to find a child guide who was captured by the mutants before her capture. After being tortured by the sadist Zirpola, and facing off against the killer of his mother, Ankar Moor (Richard Lynch), Oshay and Deneer are forced into the Death Sport (a motocross field mined with explosives).

They defeat the riders of the Death Machines easily and escape the city of Helix with two other prisoners, Doctor Karl (William Smithers) and his son Marcus (Will Walker). During the escape, Dr Karl is killed. Eventually they rescue the child from a cave of mutant cannibals, and battle the other Death Machine riders following them (destroying a fuel plant in the process). Finally they are safe, Deneer delivering Marcus to Tritan, while Kaz Oshay faces off with his nemesis Ankar Moor in "honorable" combat, using Whistlers (plastic swords that sound like music). After a bloody battle Kaz decapitates Ankar, becoming the greatest guide alive. The film ends with him and Deneer riding off into the sunset on horses."