stays true to the exuberant spirit of the Beat Generation bible with his lushly shot tableaux of post-war America.
The film, starring Sam Riley, Garrett Hedlund, Kristen Stewart, Kirsten Dunst and Viggo Mortensen, got a polite reception at its press screening Wednesday ahead of its red-carpet gala premiere later in the day.
Salles, best known for his 2004 Cannes contender The Motorcycle Diaries about Che Guevara's youthful travels, shows his heroes ploughing through drink, drugs and women as they make their way back and forth across the United States, with a stopover in Mexico.
"I've done several road movies and I realised in doing them that the more you get distant from your roots, from the starting point, the more you possibly gain perspective on who you are, where you come from and eventually who you want to be," Salles told reporters.
"But you also are (leaving) part of yourself behind."
The 56-year-old director said he had been electrified by Kerouac's cultural call to arms in a deeply conservative country while growing up in Brazil.
"What we are portraying in the film has a correlation with The Motorcycle Diaries which is about the very beginning of a social and political awakening," he said.
Kerouac, who calls himself Sal Paradise in the autobiographical novel about his wandering years in the late 1940s and early 1950s, is mesmerised by a charismatic womaniser called Dean Moriarty who has done time and lives in the moment.
Sal hits the road with him and, in between their dionysian outings, reads Joyce, Celine and Proust and begins to see how literature can be born out of raw experience.
Mortensen, who said he was also inspired by the novel growing up, plays Old Bull Lee -- a stand-in for the junkie guru Williams S. Burroughs.
The 53-year-old said the film attempted to capture the book's revolutionary drive while throwing the themes forward to the 21st-century world.
"Reading the book again, which is the first thing I did, made me realise how pertinent it is now -- protest movements, mass movements with young people in Europe, in North America, in China, the Middle East... that carry the spirit of that time," Mortensen said.
He said the film's decades-long gestation -- Francis Ford Coppola bought its rights in the 1970s and oversaw several abortive attempts to bring it to the screen -- may have in fact been a stroke of luck.
"It's probably a great time for this to come out now because I think people will look at it -- not just older people, people of my generation, people who lived through it... but young people will discover this book and identify with it I think in a very strong way."
Stewart, 22, said she had embraced the chance to abandon the virginal Bella character from the Twilight series to play the sexually uninhibited Marylou, Moriarty's wife who becomes his long-time mistress after they divorce.
The young star said her nude scenes and explicit depictions of free love had given her an opportunity to try on a new image with a compelling character.
"I love pushing, I love scaring myself. I think to watch genuine experience on screen is just so much more interesting," she said.
"The reason I wanted to do the job is because, you know, you read something, you're provoked on some level and then it's just taking that further and being able to live it and I always want to get as close to the experience as I possibly can.
"As long as you're always being really honest, there's nothing ever to be ashamed of."
The then 29-year-old Kerouac famously wrote up the novel in a three-week sitting in April 1951, typing continuously on to a 36-metre (120-foot) roll of tracing paper sheets that he cut to size and taped together.
Inspired by a rambling letter from his friend and travelling companion Neal Cassady -- who becomes Dean in the novel -- Kerouac decided to tell the story of their years on the road in a form that reflected the fluidity of improvised jazz.