When Julie Hirschfeld opened a bicycle boutique for women, she envisioned fashion-obsessed customers with a disdain for spandex flooding in to buy bikes and accessories they would model along New York City’s paved catwalks: miles and miles of new bicycle paths. She lined her shop downtown with vintage-inspired bikes, many with Brooks saddle seats; partnered with Kate Spade to sell a $1,100 bicycle the color of freshly cut grass; and sold helmets that would pass more for fashionable hats.

One year later, Ms. Hirschfeld has conceded that it takes more than fashion to get women on bikes.

“Women want to feel safe,” said Ms. Hirschfeld, who has expanded her Reade Street boutique, Adeline Adeline, to also cater to male cyclists. She said that if the perception of danger dissipates, “women then will ride, and ride more than men.”

Despite the city’s efforts to become more bike friendly, male cyclists in New York continue to outnumber female cyclists three to one, just as they have steadily over the past two decades. Data tracked by the city and private groups shows the gap between male and female cyclists is even wider in areas where vehicular traffic is more concentrated. These figures lag not only far behind those in most major global capitals like Copenhagen and Amsterdam, where women make up the majority of cyclists, but also behind American cities like Portland, Ore., that have narrowed the gender gap.

“Within the United States, New York is far behind in terms of the percentage of women cyclists compared to cities like Washington, D.C., and San Francisco,” said John Pucher, a professor of planning and transportation at Rutgers University who is working on a book about global cycling trends. “I’m convinced that one of the reasons New York City has such a low percentage of women cyclists is that it’s dangerous.”