While New York City's nearly two-week-old bike-share program already is among the largest in the world, it's passing over neighborhoods where nearly 90% of the city population lives.

The solar-powered docking stations and the nearly 6,000 stocky blue Citi Bikes are located in Manhattan below 59th Street and selected neighborhoods of Brooklyn. Vast swaths of the city—including Queens, the Bronx, Staten Island, most of Brooklyn and much of Manhattan—are left bikeless.

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