How many guys dream of saddling up and riding off into the sunset? “Just us, the wind, the road to the Pacific …” Woody (John Travolta) moons in “Wild Hogs,” and his amateur biker buddies perk up. In this low horsepower comedy of middle-aged men gone wild, though, heading for the great unknown isn’t quite so simple. There’s the wife to consider. The job. The potential paucity of Wi-Fi hot spots. If they do hit the road, Woody’s three amigos wonder, should they wear helmets? (After all, helmets prevent 62% of motorcycle fatalities.)

The target audience here would seem to be self-aware baby boomers with fond memories of “Easy Rider,” or at least “St. Elmo’s Fire.” But “Wild Hogs” — written by Brad Copeland and directed by Walt Becker, products of a younger generation — harps on its autumnal theme so insistently you’d think the midlife crisis was a foreign concept, and there’s an adolescent mean streak behind the film’s abundant gay jokes and middle-age humiliations. With a few exceptions, “Wild Hogs” is not especially funny stuff.

Woody, who exudes prosperity and alpha-male confidence, is the leader of the pack. Dudley (William H. Macy) is the poindexter. Doug (Tim Allen), an orthodontist, is the average Joe. And Bobby (Martin Lawrence) is the black janitor they’ve all been best friends with since high school (go figure). They all live in the Cincinnati suburbs, where they have achieved stability and success — or, in Bobby’s case, stability — at the perceived expense of their manhood. Some time ago, they came up with a way to reclaim it: Every once in a while, they don lots of leather and cruise around town together. So far that hasn’t worked.

Now the open road beckons — and with it the obligatory classic-rock soundtrack — and the Wild Hogs can’t resist. But the first Lynyrd Skynyrd tune hasn’t even faded out before they find themselves in front of a campfire with Doug asking, “Did you ever wake up and wonder what happened to your life?” Before anyone can respond, a misplaced marshmallow sets their tent aflame. (Conflagration gags haven’t been funny since the silent era, but this one comes as a relief.)

The next day, the Hogs are hounded by a state trooper (John C. McGinley) who’s convinced four men sharing a mattress in the woods must also share his idea of a good time. A decision to go skinny-dipping has embarrassing results. Later, in New Mexico, the Hogs stumble upon a real biker bar. Not surprisingly, its regulars aren’t big fans of BlackBerry types, especially those who impersonate bikers. In case there was any doubt at this point that our heroes are a bunch of sissies who should just go home, their chief antagonist (Ray Liotta) spends five minutes screaming just that in their faces.

What began as gentle self-mockery takes on a less pleasant dimension here, and it’s not because Mr. Liotta’s acting is totally out of control. You begin to feel a twinge of pity for these guys — Mr. Allen’s Doug in particular, perhaps because he is so bland yet believable. Twenty-five years removed from high school, they just want to be cool again, and they get a chance when a small town of decent folk is menaced by Mr. Liotta’s biker gang. But the Hogs don’t exactly acquit themselves with dignity. The Magnificent Seven they are not.

As comedy — or anything else, for that matter — “Wild Hogs” falls just as short. Dudley, a know-it-all computer programmer who’s pathetic with women, is the only consistently funny character, though various animals give him a run for his money. He falls for a woman he meets in New Mexico, who reassures him that though he may not be all that virile, she likes him because he is sweet and honest — “the type of man that’s really hard to find.” I would make a stink about how this casual assumption has become a tired staple of romantic comedies, except it is delivered by Marisa Tomei, who can still turn a guy to mush 15 years after “My Cousin Vinny.”

Let’s get real, though. Dudley and his friends (as the film does not fail to suggest) could sue the pants off those redneck bullies if they wanted to. For some reason, they don’t really stick it to them until the credit-crawl epilogue, when the biker bar gets a makeover. Looks like those thugs got a dose of the tough stuff after all: gentrification.