Ok this ain't a film but the episode of The Simpson's when Homer wins a Harley. Beats all of the previous mentioned scenes in my book.
Saying that he did ride one in The Simpsons Movie.
Mad Max and all those Rickman faired Z 1000's and Goose's Police bike, and who could forget the Toecutter.
Mad Max 2 and those survivalist bikes
and a forgotten classic, Stone. The funeral cortege with the coffin on the Racing Sidecar Unit sweeping down the motorway followed by hoardes of bikers 2 abreast.
What was that British horror film where the teenage thug / biker died and was buried with his bike, but wouldn't stay dead? lol
It must be the first horror film to put me to sleep