Tim Allen does eat like a pig in one scene of “Wild Hogs.” The rest of the time, though, Allen and biker buddies John Travolta, Martin Lawrence and William H. Macy are not all that wild, and more importantly, not all that funny.

The road romp from director Walt Becker is like his “National Lampoon’s Van Wilder” on Maalox, the humour and hijinks tame and tranquil as though it were a middle-aged epilogue to that raunchy campus comedy.

The script by Brad Copeland, whose sharp TV credits include “My Name Is Earl” and “Arrested Development,” even has references to Allen’s character as a former fearless party animal, a Van Wilder now lapsed into soft, safe suburban catatonia.

Like last year’s execrable Robin Williams’ road comedy “RV”, “Wild Hogs” has little story and even less characterisation to its stereotyped players.

The filmmakers simply fashion an excuse to send their weekend motorcyclists onto the highways, then string together uninspired encounters with some fellow travellers and a hardcore biker gang headed by Ray Liotta, whose enthusiastic bad-boy performance is wasted in a woefully underwritten role.

Becker and Copeland start with a sketchy glimpse of the four men’s lives. The ringleaders are Allen as dentist Doug Madsen and Travolta as Woody Stevens, a businessman with a supermodel wife and big secrets he conceals from his pals.

In their spare time, Doug and Woody cruise with chums Bobby Davis (Lawrence), a plumber with a domineering wife, and Dudley Frank (Macy), a klutzy computer programmer who’s afraid to talk to women.

The four men wear leather jackets emblazoned with the logo of their little Wild Hogs biker clique and ride Harleys around suburban Cincinnati to escape their humdrum lives for a few hours.

Then Woody proposes a cross-country trip to the Pacific. The others are quickly on board, and off they go, sputtering through a fitful series of incidents highlighted by a mildly amusing bit with John C. McGinley as a motorcycle cop.

There are a couple of genuinely funny sight gags, but most of the roadside attractions of “Wild Hogs” are either boring or outright annoying, particularly repeated segments of Kyle Gass (Jack Black’s partner in the musical duo Tenacious D) as a bad singer at a local chili festival.

Marisa Tomei, Jill Hennessy and Tichina Arnold barely register as wives or lovers of our heroes.

The movie’s main conflict arises after the Hogs cross paths with the Del Fuegos, a band of desperado bikers. The filmmakers seem to have no clue what to do with their battling bikers once the inevitable showdown rumble begins.

The only reason the resolution of the boys’ crisis remotely works is because of a surprise guest, an icon of biker flicks past, who makes an out-of-the-blue appearance to awkwardly settle all scores and send everyone happily down the road.

Without that cameo performance, “Wild Hogs” would be a breakdown along the highway, waiting for a tow to fetch it home.“Wild Hogs” is rated PG-13 for crude and sexual content and some violence and is showing at the Liberty Theatre.