Born in the streets of Oakland, scraper bikes first gained attention as a trend in bicycle customization that spread with viral speed, thanks to YouTube. Since the Scraper Bike video debuted two years ago, they’ve become much more: a practical means of greening urban space, a social movement, and a rallying point for young people organizing against violence in their communities.

Tyrone "Baby Champ" Stevenson, who styles himself the Scraper Bike King, says the first scraper bikes were created by Oakland teens who coveted, but could not afford, scraper cars — souped-up sedans painted with bright colors and with rims so large they scrape the undercarriage. Scraper bikes are such a hit that many teens skip the cars and keep pedaling well past the age of 16.

On July 25, Stevenson organized the second annual "Bike 4 Life" ride to call for an end to violence in Oakland’s neighborhoods. "We’re trying to bring together a gun truce," he says, "because a lot of people in our community are dying from guns." This Streetfilm features scenes from the ride and more from Stevenson about the movement he helped launch.