The imagery and music of Easy Rider has become synonymous with a generation of long-haired, carefree men with a penchant for motorcycles.

The imagery of the desert rolling by, reflected in the chrome of the bikes, is a perfect representation of the Great (American) Outdoors. According to the film's tagline, Easy Rider is: "The story of the man who went looking for America and couldn't find it anywhere" - what he could find was a soundtrack which changed the game when it comes to scoring movies.

Nowadays it's common, but before Easy Rider it was highly unusual to have previously released music in a film. There were exceptions such as The Beatles films of the time, but for a straight-up motorcycle movie to have current music was revolutionary. Using licensed music cost $1m which was almost three times the budget spent on the rest of the movie. The film itself even features musical in-jokes with rock and roll super producer Phil Spector making a cameo as the bikers drug dealing contact.

The title sequence song - 'Born To Be Wild' by Steppenwolf - wasn't even meant to be used in the movie. It had been there as a placeholder as Fonda had wanted Crosby, Stills & Nash to do the soundtrack but Hopper was adamant that the guys who drove around in limos would have no idea what the film was about. It was an inspired placeholder as the song has gone on to soundtrack countless 'wild' montages in films as diverse as Borat and Nymphomaniac.

Easy Rider was a huge commercial success despite modest expectations. It's a film which made the stars a lot of money and in the paraphrased words of Roger Ebert, would make Peter Fonda rich from a film his father could not understand. The film itself pays homage to the trailblazing musicians of the late '60s like Jimi Hendrix. His track 'If 6 was 9' plays as Wyatt and Billy roll into the backwater Louisiana town.

The irony isn't lost by having a black man singing rock and roll music soundtracking the journey into what is soon to be revealed as a heavily prejudiced place. The initial shots of the town show pristine Antebellum architecture (built on plantation money) before revealing the less glamourous locations of the town's black residents. The bikers liberal attitudes (and by extension the film's message) are critical of outdated ways of thinking about relationships between American citizens, and this choice of song illuminates this idea.

The film's close relationships to the musicians whose work they featured meant using the music was often a simple process. However, the film's most interesting musical story comes from a lack of understanding. According to an interview with Sabotage Times, Dennis Hopper had said that Peter Fonda had initially wanted to use Bob Dylan's 'It's Alright, Ma (I'm Only Bleeding)' in the film but Dylan himself rejected the approach as he didn't like the film and Billy's anti-hero status. Dylan relented slightly and allowed the filmmakers to use Roger McGuinn of The Byrds' cover version instead. According to legend, Dylan also scribbled the lines - "The river flows, it flows to the sea/Wherever that river goes, that's where I want to be/Flow, river, flow" - onto a napkin, before telling Fonda to "give this to McGuinn. He'll know what to do with it."

McGuinn then expanded the words on the napkin into the film's theme song 'Ballad of Easy Rider'. But despite this gift to Fonda, Hopper and McGuinn - Dylan demanded his name be removed as a co-writer of the track due to his disdain for the film and his perceived notion that his name would be used to add credibility to the movie. Regardless, the song and the score have been a symbol of American counterculture for the past forty plus years and have soundtracked many a journey into the American Great Outdoors.