It's A Revolution Mother 1969 Written by Thomas Casey and directed by Harry Kerwin. This scruffy documentary is part of a three film set called Biker Triple Feature, all three films on one disc, I got it from Amazon for 8 bucks, it's still for sale. The other two films are fictional and star Jack Nicholson. The film is called Biker Babylon on the DVD.
It's a Revolution Mother looks at the youth counterculture of the late sixties. There's plenty of raw footage shot live on the street and it's entertainingly narrated by some unknown guy.
The film starts with the New Jersey motorcycle club The Aliens. There's some sitting about and talking, cut with plenty of motorcycle riding. Then the setting moves to a big march on Washington and the delivery of a bunch of white coffins filled with placards worn by the marchers. The placards have names on them, names of the fallen soldiers from the Vietnam war.
The last segment of the film moves to a more upbeat place, a sea of mud in Florida with a big 30 band rock festival. Oddly they never mention the name of the festival but there was a big one in Miami at a racetrack in December 1968. I'm betting that it's it based on some quick internet sources, especially after seeing some of the aerial shots.
It's a nice snapshot whether you agree with the sentiments. Glad to have seen it.