Even Citi Bike’s most ardent supporters couldn’t have foreseen its biggest problem: The bike-share service is just too popular. In the East Village, most docks are empty after morning rush hour and filled to the brim after six, forcing bikers to search the neighborhood for an open space (negating much of the convenience). There is one, however, that seems to be the Goldilocks of Citi Bike hubs: 9th Street and Avenue C. Never empty, never full, this rack is a good bet every morning. Sitting two blocks from East River Park, it’s a perfect place to start your commute to midtown or Wall Street. Plus, you can fuel up at Ninth Street Espresso, which sits across the street. Trust us: A double Americano makes that morning trek so much easier.