If you liked the movie “Big” about a boy-turned-man or just want to relive your childhood, you might find yourself caught up in a wacky craze over pint-size motorcycles.

Called "pocket bikes" (search) and originally created for racing, the li'l cycles are catching on like mad across the country, particularly among teenaged and 20-something guys — who don’t seem to mind looking like adults on kids' toys as they zip around hunched over on the too-small motos.

“They think they look cool,” said Linda Ma, a partner at Fancy Scooter in New York City, which sells pocket bikes and other two-wheel novelty contraptions. “They feel powerful.”

The trend has really taken off in the last year or so. At the International Motorcycle Show (search) in January, they were practically zooming out of the booths.

“People were going crazy for them,” said Jay Robertson, a vehicle sales consultant for Harley Davidson in Stamford, Conn. “It’s a recent explosion. This is happening all over the place.”

The bikes are smaller, lighter and cheaper than their adult-size counterparts, with price tags in the $200-$3,000 range, as opposed to the regular motorcycles that cost a minimum of several grand. They are also illegal for street use in most states, but enthusiasts who are attracted by their low cost and cachet can't get enough of them.

“They’re affordable, convenient and gas-efficient,” said 19-year-old Alex Li, a Brooklyn college student looking to purchase a pocket bike at Fancy Scooter last week with his brother, Joseph. “It beats getting stuck in traffic, and it beats walking. Sometimes you like the breeze in your face.”

Like scooters and mopeds, pocket bikes aren’t allowed on the highway. Other road rules vary by state, but basics like registering them and equipping them with license plates and lights apply, according to Robertson, whose dealership doesn't sell the minis.

Pocket bikes are ubiquitous in California, where police have been cracking down on riders after a number of recent accidents. On the other side of the country, in New York, the little motorcycles are illegal on public streets, but the laws aren’t heavily enforced in many jurisdictions, according to those in the know.

“A lot of people ride them,” Li said of pocket bikers in his Brooklyn neighborhood, Bensonhurst. “The cops have other things to deal with. They have real criminals to deal with.”

Howard Wu, a partner at Fancy Scooter, said he and Ma suggest that buyers ride the pocket bikes in the park or at the beach, advise them of the state laws and warn them to wear helmets and proceed with caution.

“We don’t encourage small kids to ride,” Ma said. “They’re built for speed and if you go very fast, it’s going to hurt you.”

The larger versions of the mini motos hit speeds of 20 to 25 mph, but the smaller ones can go up to 50 mph.

“Of course they’re dangerous,” said Robertson. “You’re going 25 miles per hour and run into a car or a wall, you’re going to come away with some scrapes and bumps and bruises. They’re so small and low it’s possible that a driver in a vehicle would not see you and just run over your ass.”

On the other hand, he added, pocket bikes are light and low to the ground, so if an accident happens it might not be as serious as one on a heavy-metal, full-size motorcycle.

“If you fall off, you’re already only six inches off the ground,” Robertson said.

A recent test drive of a Fancy Scooter mini proved that the toy-sized cycles are zippy, fun, loud and fairly simple to learn to ride — but are likely to cause leg-cramping for anyone who isn’t ultra petite.

“I don’t think it’s comfortable, but the speed and the noise it makes are the attraction,” said Wu.

Still, some don’t see the appeal of being hunched over on a minuscule bike.

“It's like a baby bike,” said Ted Smolar, 28, of Israel, who was buying a stand-up scooter at Fancy Scooter instead.

Ninety percent of customers who do buy the small cycles are male, according to Ma. And Smolar’s female cousin certainly wasn't overly eager to hop on a pocket bike.

“I think it’s really a guy thing,” said Esther Garfin of Toronto, Canada. “I like cars.”

Like any trend du jour, the mainly male fascination with the tiny two-wheelers will probably be fleeting, said Robertson.

“It’s a fad,” he said. “Eventually, it will go the way of the Dodo.”