STURGIS, S.D. -- Baby boomers are driving much of the increased popularity in motorcycling -- and it's quite visible at the 66th Sturgis Motorcycle Rally.

Most bikers these days have raised a family and can afford the sport, said Pepper Massey-Swan, executive director of the Sturgis Motorcycle Museum and Hall of Fame.

''People who have lived a very respectable, steady life. You know you've worked your butt off, you want to get out there and do something crazy. Tell me what it feels like to throw a leg over and go 75 miles an hour down the highway. It's a pretty good feeling,'' she said.

Motorcycle and scooter sales have been up each year for the last 13 and rose 5 percent from 2004 to 2005, according to the Motorcycle Industry Council.

Harley-Davidson, which claims about half of the large bike market, has seen sales increase from 234,461 in 2001 to 329,017 in 2005.

''The industry's growing, the market's growing,'' said Paul James, communications manager for Harley-Davidson.

''Demographics are playing into our favor. We have a lot of baby boomers who are coming into where they have money and time to spend. A lot of them were riders in the '60s and '70s and are coming back after they raised their families,'' he said.

The company has its 2007 line on display and available for demo rides at the Civic Center in nearby Rapid City during the rally.

Other younger companies also are thriving.

L.T. Little of American Ironhorse Motorcycles said the company started 10 years ago because people had to wait too long for a Harley and wanted to design their own bike from the ground up.

''They want to be different than everyone else that rolls up on the exact same looking motorcycle from other manufacturers. They want it personalized. They to be an individual,'' Little said.

Ironhorse cycles range in price from $28,000 to $46,000, so its clients are higher income, he said.

''You give me the money for one?'' Dan Panzer of Ellsworth, Kan., quipped when asked if he'd like one.

Harley-Davidson's run $6,500 to $20,000, and company has also responded to the desire for people to customize their bikes, offering more than 7,000 options, James said.

Little said the popularity of television shows featuring Orange County Choppers and West Coast Choppers also fuels interest in custom bikes.

Bob Brown of Waukee, Iowa, bought his first chopper 10 years ago and is riding this year on a new bike made for him by New York City Choppers. It's a bobber, which has slightly shorter forks than a chopper. His has artwork of Marilyn Monroe on the gas tank.

''They're not so stretched out, easier to maneuver, but it still has the look,'' Brown said. ''I like it to look a little retro, that 1950s-'60s retro look.''

A lot of the bikers are women, such as Holly Best of Muscatine, Iowa, who got a Harley three years ago for her 50th birthday.

''It's just a way of life, is the only way I know how to describe it to you,'' she said.

Tom and Sandra Uecker of Edgar, Neb., say loyalty and the lack of seating room for two people on a chopper will keep them riding a Harley. Otherwise she couldn't come along.

''If I have to choose between a warm bed and a good motorcycle, a good motorcycle is second,'' he said.