“Hard Miles” is a sweet, unassuming and generally unsurprising dramedy about changing lives via cycling and seeing The Grand Canyon.

This “inspired by” a true story stars Matthew Modine as a social worker/counselor who hits on the idea that his road biking obsession could be transformational for the “delinquents” he’s trying to keep out of the Colorado prison system. Director R.J. Daniel Hanna and co-writer Christian Sander find an inventive, roundabout way to may this happen, throw in assorted conventional “obstacles” along the way and get a pleasant if slack feel-good movie out of it.

Modine plays Greg Townsend, long and lean and well over 50, a man who has devoted his life to interrupting the downward slide of boys “in the system” who might be saved if they learn the right lessons at Ridgeview Academy.

With hotheads, car thieves and gang members “processed” back and forth between the boarding school and the prison system, it’s an uphill climb. But Greg knows something about those. His long bike rides through the mountains build character.

Hey, howabout redirecting kids from a backpacking trip where they can be “rehabilitated by tall trees,” and taking them on a long cycling/camping trip throught the Grand Canyon? The boss’s dream, because they’re always about to lose their funding and certification, is doing any activity “looks great on Facebook.”

Boss Skip (Leslie David Baker of “The Office”) is sold. But if he knew this was just so Greg can combine work, get in his long-planned 762 mile ride in, and maybe drop by the hospital where his abusive father is about to die, he might not be.

Greg’s avocation training responsibilities include welding class. Great. They can “build their own bikes.” He’s pals with the bike-shop owner who gets all his business (Sean Astin). Maybe he’ll “sponsor” the “team.”

Get some donated wheels and brakes and seats and gears, acquire helmets, shorts and “Banda di Catene” (“Chain Gang” in Italian) T-shirts, convince co-worker Haddie (Cynthia Kaye Williams) to drive the support van, aka “The Slack Wagon,” and they’re off.

Well, the four metal shop kids Greg has in mind for this “Outward Bound on Bikes” experience will have to be convinced. But what else are car-thief Woobright (Jahking Guillory), gang-banger Atencio (Damien Diaz), brawler Rice (Zachary T. Robbins) and eating disordered head-case Smink (Jackson Kelly) going to do with those nice frames they’ve brazed together?

Greg will pass on maxims like “You know what overcomes hard luck? Hard work.” And the lads will learn to work as a team, a peloton of riders, each with his role in the pack.

Flashbacks will give us a taste of Greg’s past. Phone calls from prison tell us how his life might’ve gone. And a lone flashback suggests what one of these boys lived through.

Mainly this is about the riding, the scenery and the foul-mouthed insults and wise-cracking.

Maybe I missed it, but the last time I checked, an eating disorder won’t land you in a juvenile detention/boarding school. A detail missing from an incomplete yet overlong tale. The kids are barely sketched in, the obstacles they overcome are skimmed-over and Greg’s personal issues are perfunctory and arrive, like clockwork, to prop up the drama of it all.

There’s nothing all that “hard” in these “Hard Miles.” It passes the time with some pretty sights, fairly worn cliches and semi-serious cycling, a pleasant-enough dramedy that never gets out of the low, easy gears.

Rating: PG-13, some violence, profanity, teen drinking

Cast: Matthew Modine, Jahking Guillory, Cynthia Kaye McWilliams, Jackson Kelly, Damien Diaz, Zachary T. Robbins, Sean Astin and Leslie David Baker.

Credits: Directed by R.J. Daniel Hanna, scripted by R.J. Daniel Hannah and Christian Sander. A Blue Fox release.

Running time: 1:50