Over the last four years, the streets of New York City have undergone a transformation: More than 250 miles of traffic lanes dedicated for bicycles have been created, and several laws intended to promote cycling have been passed.

The efforts by the Bloomberg administration have placed the city at the forefront of a national trend to make bicycling viable and safe even in the most urban of settings. Yet over the last year, a backlash has taken hold.

Bowing to vocal opposition from drivers and elected officials, the city last week began removing a 2.35-mile painted bike lane along Father Capodanno Boulevard on Staten Island. In Manhattan, a community board held a special hearing this month for business owners to vent about problems posed by a new protected bicycle lane on Columbus Avenue — in particular, the removal of parking spaces and the difficulty of getting truck deliveries.

In Brooklyn, new bicycle lanes have led to unusual scenes of friction. Along Prospect Park West, opponents protested last month alongside supporters of the lanes. And last year, painted paths along Bedford and Kent Avenues in Williamsburg caused disagreement between cyclists and Hasidim. The lane on Bedford Avenue was later removed.

So far, the opposition to the city’s agenda on bicycles has far less organization and passion than the bicycling advocates, but it is gaining increased attention.

The City Council will hold a hearing on bicycling on Dec. 9 to address balancing the needs of cyclists with those of other road users, said Councilman James Vacca, the chairman of the Transportation Committee. The hearing will also look at how well the Transportation Department has worked with community boards to review large-scale road changes.

Police and transportation officials, meanwhile, have begun a crackdown on bicycle-related traffic violations amid complaints from some pedestrians.

Surging bike ridership has created a simmering cultural conflict between competing notions of urban transportation. Many New Yorkers object to bicycle lanes as sudden, drastic changes to their coveted concrete front yards.

“He’s taking away my rights as a driver,” Leslie Sicklick, 45, said of Mayor Michael R. Bloomberg. Ms. Sicklick, a dog walker and substitute teacher, grew up driving with her father around the Lower East Side, where she still lives.

She organized a protest in the East Village last month, and she and at least two groups of opponents are planning new rallies against local bicycle lanes. They have discussed joining up for one large protest, though none has been planned.

Cycling advocates have taken notice. They have begun to mobilize more — seeking to undercut any antibicycle rally by their own presence — and have increased pressure on city officials to continue the pro-bicycle agenda. On Nov. 10, for example, advocates and bike riders massed in front of City Hall to protest the Transportation Department’s decision to scale back on parking-protected lanes along First and Second Avenues.

“It’s easy to focus on some of the conflict and friction,” said Paul Steely White, executive director of Transportation Alternatives, a bicycle and pedestrian advocacy group that has seen its influence grow under the Bloomberg administration. “But that’s always going to happen when you’re changing the geometry of something as dear as the asphalt. It takes some adjustment, and we’re definitely in that adjustment phase.”

There have been no independent polls of New Yorkers’ attitudes on bicycle lanes, though online surveys have proliferated in recent weeks. One such survey, focused on Prospect Park West in Brooklyn and sponsored by the City Council members representing Park Slope, has received thousands of submissions. “It’s a study period — that’s how D.O.T. put it,” one of those members, Councilman Brad Lander, said. Results should be ready before January, when the department is likely to reach a conclusion on whether the Prospect Park West lane has been a success.

New York has a long relationship with the bicycle, with the first bike path in the country running along Ocean Parkway in Brooklyn as early as 1894.

Interest in better bike infrastructure was revived under Mayor John V. Lindsay in the 1970s. The first separated bike lanes, similar to those that now exist on sections of Eighth and Ninth Avenues in Manhattan, were installed by Mayor Edward I. Koch in 1980 on Avenue of the Americas and Seventh Avenue — though they were quickly removed amid fierce opposition.

“What we did was on such a small scale,” Mr. Koch said recently. “What’s being done now is on such a large scale.”

Along with pedestrian plazas and new express bus service lanes, improved bicycle infrastructure is part of a city effort to rebalance the mix of cyclists, pedestrians and cars on the streets. Slowed motor traffic — “traffic calming” — is one of the department’s goals for new bike lanes, to the annoyance of many drivers.

The Transportation Department has responded to criticism by pointing to accident data showing a correlation between new lanes and increased pedestrian safety. Fatal crashes have decreased on streets with new lanes, according to the department.

“The record speaks for itself: Injuries have dropped, dramatically, for everyone on streets where bike lanes have been installed,” said Janette Sadik-Khan, the transportation commissioner.

The department pointed to the support lanes have found from community boards across the city, many of which have explicitly requested new bike lanes — along Prospect Park West, for example — in part because of safety concerns.

Outside the city, bikes have begun creeping into political battles this year. The Republican nominee for governor of Colorado, Dan Maes, wondered during the primary whether bicycles were part of a plot to ruin cities.

Mayor Adrian M. Fenty, who lost his bid for re-election in Washington, found himself painted as out of touch with residents, in part because of his connection to new bike paths.

In New York, the biggest challenge yet could come along Prospect Park West, where some residents are fighting to eliminate the 1.8-mile, two-way strip of green paint delineating a new bike lane.

Norman Steisel, a former sanitation commissioner and deputy mayor, admitted that he never noticed the proliferation of bicycle lanes, until he got stuck in traffic near his Brooklyn home over the summer.

“I was shocked; I thought there had been a big accident,” Mr. Steisel said of a back-up on Carroll Street that he later attributed to a new bike lane. “I guess I wasn’t paying attention.”

Mr. Steisel was among opponents who staged a protest on Oct. 21, but they were outnumbered more than three to one by supporters.

“We don’t want to be out here having to advocate for something that’s already done,” said Eric McClure, who lives in Park Slope. “But here we are.”