One rite of spring in New York is dusting the spokes off your ten-speed that’s been nestled between the boiler and nineteen half-empty cans of Provençal-yellow paint and hitting your favorite bike path. But first, your chain needs oil, your tires need air, and your brakes need more work done on them than a Gabor sister. National-time-trial-champion cyclist and three-time Tour de Francer Elizabeth Emery (of team Celestial Seasonings) gets her bike repaired and prepared at Metro Bicycles (1311 Lexington Avenue, at 88th Street; 427-4450). “Carlos Plaza Metro’s head mechanic is the best mechanic around, fixing and sprucing up my bikes with incredible reliability,” assures Emery, adding, “They’re so friendly, helpful, and knowledgeable about all levels of bikes and equipment.” Tune-ups start at $48, major overhauls at $120.