Just after 9/11, Meg Crouse, like millions of other Americans, began taking stock of her life. She had a new awareness of how fleeting human existence could be, and she wanted and needed more adventure. She also was approaching 50, and that, too, meant a reckoning.

So Crouse did something she'd always yearned to do: She learned to ride a motorcycle. And then she bought one.

"I'd always been enthralled by motorcycles," Crouse said. "Once, my mother caught me ogling some guys on bikes. I had to explain to her that it wasn't the guys - it was their bikes I was ogling."

Crouse, who recently retired from her 34-year career with the federal government as a manager for the IRS, is now officially the owner of a beloved Harley-Davidson Sportster of her own.

She is both biker and grandmother, a tattooless volunteer for the local SPCA and a community theater group. Of the saddlebags that travel with her on long rides: "One is a standard Harley-Davidson bag and the other is a Talbot's bag. I have some of both in me, and that's how I like it."

Crouse also represents one of motorcycling's up-and-coming demographics: the baby boomer woman biker.

The Motorcycle Industry Council, a not-for-profit national trade association based in Irvine, Calif., estimates that the number of female riders in the United States grew 32 percent, from 4.3 million in 2003 to 5.7 million in 2008, the latest year for which statistics are available. And these female riders, median age 41, also are spending money on their pastime. By 2008, women were 12.3 percent of new motorcycle owners, up from 9.6 percent in 2003.

"This is a female population that doesn't want to ride on the back of the bike. These women have the financial resources to buy bikes of their own," said Barb Borowiec, 47, owner of Barb's Harley-Davidson in Mount Ephraim.

Borowiec's own passion for motorcycles began in childhood. In 1983, when she was 20, she walked into a dealership and bought her first Harley. "At that time, I knew of only two other women in South Jersey who rode."

That was then. Borowiec bought that dealership with two partners in 1997; today, she owns it alone and employs a staff of 48. Ten percent of her customer base is female, and that percentage grows with every all-full, women-only riding class she hosts. Her other women-only events, including periodic "garage parties" designed to introduce potential bikers to bike veterans, have attracted hundreds.

"It's a different industry now," Borowiec said.

Jessica Prokup, spokeswoman on emerging markets for the Motorcycle Industry Council, is seeing more women buying bikes at milestone birthdays. "What we hear often at consumer shows is that baby boomers, many of whom are empty-nester women, are excited about doing something different for themselves," said Prokup.

The baby boomer mentality is definitely at work in the world of motorcycling, said Melissa Stein, a postdoctoral fellow with a specialty in American history and gender studies at Indiana University in Bloomington. "This female population especially seems to need to idealize nonconformity, and many resolve absolutely not to be their mothers," who were part of the vast domesticity movement after World War II.

"Getting on a motorcycle suggests scoffing at aging, and literally riding into freedom," said Stein. "On a motorcycle, you have speed and excitement at the very time when you want to defy surrendering to an aging body."

Two years ago, at 55, Crouse joined two male friends on a trip across the country. "On that bike, I'm young and free. I've discovered new parts of myself that I like very much, and boy, do I feel empowered."

On a recent morning outside a Delran coffee shop, a group of bikers gathered before a ride out to Batsto, a historic village in Burlington County, and then for lunch at Pic-A-Lilli, a popular spot for cyclists in the Pinelands.

Of the group, Tina Ott, 47, an administrative assistant, is a grandmother who enjoys the great outdoors.

Carol Bassel, 50, a Curves franchise owner in Delran, likes the adventure. "I'm determined to squeeze every drop out of living, and that motorcycle makes life happen for me. My joy is in the journey."

Michele Visconti, a single mother and the "baby" of the riding group at 44, took the plunge, got licensed, and bought her own bike three years ago. Her gleaming black Harley often takes her to work at the Riverside lighting company where she handles customer service.

The women all agreed that bikers look out for one another, making everyone feel protected. "This is really like a family," said Visconti. "You care about each other - and keep your eyes wide open."

In fact, she often rides with her 11-year-old son, Zachary, and is appropriately obsessive about safety. "I'm teaching him to be conscious of it, too - it's great training for any kid."

For 48-year-old Debra McMullen of Maple Shade, a banker and mother of four adult children, biking is a diversion. "I can make a 300-mile trip out of going to breakfast or lunch." She rode from South Jersey to South Dakota for a biker rally two summers ago on her 2006 Softail Harley. Painted periwinkle blue, the bike is studiously devoid of decoration. "I'm a cycle purist."

Others are taking advantage of an increase in female-specific merchandise, and it's not much different from what you'd see on the fashion runways.

"The big colors this spring and summer are turquoise and hot pink," said Borowiec; a staff of 10 runs her women's fashion department.

Along with logo items with the classic Harley-Davidson bar and shield insignia, there are jackets, pants, even sleepwear. There are five-pocket jeans, with a coin pocket on the left to facilitate paying tolls. Shirts are cut longer in the back to allow a woman to reach the handlebars and not give drivers behind her a peep show. "We also have belts with lots of bling," said Jackie Berrios of Brian's Harley-Davidson in Langhorne.

Helmets, Berrios reports, may be daintily decorated with roses - or laden with Swarovski crystals.

Even the cycles can be specifically fitted for the female frame.

Take Evy Rivera of Philadelphia. At just 4-foot-10, Rivera, 48, an assistant director of client services with the Kimmel & Silverman law firm in Philadelphia, dropped nearly 200 pounds several years ago. Having cause to celebrate, she got off the back of her husband's bike and onto her own - but not before getting a totally customized bike just her size.

Now a licensed rider, Rivera has a special interest in using her cycle for patriotic events. She also is part of her church's biking group, the "Calvary Riders" of Davisville Baptist Church in Bucks County.

"There are about 16 of us now, and only two of us are women. But more women in the church are telling me that they're ready to join," said Rivera, who said she was delighted to lead the trend. "I think that just seeing me enjoying myself so much has motivated them."

Silver-haired Jacky Kauffman of Bensalem, a co-owner of her own marketing/communications company, may dress conservatively in her working life, but she is a proud member of HOG - the Harley Owners Group.

"I wasn't allowed to date boys who had motorcycles," said Kauffman, 58. "But I married a guy who did, and had to keep it from my late mother, until she discovered Alan's secret on her own. She was fine with it after all."

It took several decades for Kauffman to ride herself. Three years ago, she took the plunge. "I'm loving it. I feel free, I feel empowered, and I've found the perfect way to unwind."

Asked what she likes most about riding, Kauffman doesn't miss a beat: "Everything."