RaceFace Era SL Rear Wheel - 29", 12 x 148mm, 6-Bolt, XD, Carbon BlackRide Light. Log Miles. Get Loose. The Era SL wheel was designed to bridge two riding disciplines with the goal of excelling at both ends of the spectrum. Not your typical XC race wheel, nor a strength forward Enduro wheel. A happy medium, designed specifically for the mass of riders who sit happily in between. At 385 grams, the Era SL rim is the lightest ever produced by Race Face. That low rotational mass allows quick acceleration and maintains