It’s Sunday morning and a group of bikers are taking turns riding a hardtail chopper around an oak tree covered hill in California. But this isn’t just another group of weekend warriors. There’s a small film crew capturing the shenanigans and giving interviews. This outfit is a clump of veteran Dirtbags and they’re filming a promo video for an ambitious project entitled “Rigid: A Dirtbag Challenge.” These bike-nuts plan to ride home-built, hardtail choppers across the country on the 5,000 miles of unpaved roads that make up the Trans-America Trail.

To understand how this crazy scheme was hatched, you must first understand the Dirtbag Challenge. Held each fall in San Francisco’s Hunter’s Point district, the Dirtbag is a low-rent biker build-off that gives entrants one month to make a sweet ride for under a thousand bucks. It began a little over a decade ago, when head Dirtbag Poll Brown and some friends were trash-talking the ridiculously expensive, rolling chrome museums of American Chopper. The friends basically dared one another to build bikes for a grand in almost no time.

Today the Dirtbag Challenge attracts thousands of folks and sees some pretty impressive builds. Not least impressive were the bikes built by Casey Anderson. When he heard about the Dirtbag, Anderson was already building custom bikes. He quickly clicked with the other motorcycle miscreants and became a regular Dirtbag competitor.

Anderson and Brown got along so well that they entered a coast to coast hardtail chopper race together. The Stampede was fun but aside from the ungodly pace of the fastest riders, they didn’t find it all that difficult. While camping one night, they got to talking about the Trans-America Trail. Now there was something that would challenge their riding and building skills. No gas stations or hardware stores. Choppers without a net.

Shortly after the Stampede, Anderson bought some Honda Trail 90s and they headed east from the Oregon coast. But it turned out to be a little too daunting. Not only were the western slopes steeper than their eastern counterparts forcing the group to reroute several times, but the trip also saw a couple riders injured and a blown engine. In the end, only one of the original five finished the ride. A postmortem resulted in two decisions: they needed bigger bikes and would start from the east next time.

Months later, Brown discussed the trip with filmmaker Paolo Asuncion, who had documented Brown and other builders in his first feature film, “Dirtbag.” It seemed like a natural chance to make another film together. The project was dubbed “Rigid” for the rigid frames they plan to ride. The profits from the film have been slotted towards a pediatric cancer charity. This is partially in hopes that the community will support a project that aims to do more than just show off three-quarter helmets and mustaches. But moreover, as many of the crew’s lives have been touched by cancer, this was an obvious way to make the ride more meaningful and fulfilling. At the end of the day, these guys just want to do the ride.

The group was to depart in early June but, much like the steep slopes previously encountered, they were met by insurmountable obstacles. Going on a ride is one thing, but the riders are financing their own builds and travel costs, so making an independent documentary of the experience has turned out to be an entirely different beast. Icon and the Dainese San Francisco store have pledged riding gear sponsorships, and local shop Motopia has promised to supply the film crew with a bike. But the production end - the actual filming - still needs funding or sponsorship.

A used truck had been procured, and the team was prepping a bike to raffle off in order to raise money. But the talented Turk was drawn away to the East Coast to tend to the health of his father. Meanwhile, Anderson had an epiphany, realizing that he wasn’t living the life he wanted. He has since sold most of his possessions and is shipping a truck, a couple of bikes and his dog out to Hawaii.

With a half-finished raffle bike, a production vehicle still in need of repairs, and Turk’s family concerns up in the air, the crew chose to regroup and aim for next summer. While this is certainly a setback, Brown and Asuncion are trying to spin it into an opportunity. They’re hoping this will give them a chance to get more in depth, to build better bikes, get more funding and sponsorship. With any luck, they will eventually produce a better film and raise more money for charity.

Between now and the release of "Rigid", the guys are releasing several mini-movies in the form of an episodic web series called "The Road to Rigid", sharing the struggles that come from making an independent motorcycle film. The first episode can be seen here. More info on the project: Facebook.com/RIGIDfilm