Fulcrum Speed 42 Rear Wheel - 700 12 x 142mm CenterLock HG11 BlackFulcrum Speed 42 Rear Wheel 700 12 x 142mm CenterLock HG11 Black. Speed 42 wheels are the culmination of a process that included over 4000 hours of testing in the wind tunnel laboratory and the open road to achieve the best performance in terms of aerodynamics rolling resistance lightness and handling without compromising safety. An evolution without compromises: the new rims (higher wider lighter and more aerodynamic) combined with new hubs and