Fulcrum “step into a new era and dimension” with their new Speed 42mm and 57mm rims, replacing the 40mm and 55mm sizes, a result of synergy between form and function, or as they put it: “Form, Function, Fulcrum”.
The new wider rims when paired with 28 mm tires, provide a level of performance without compromises, with optimum aerodynamic penetration, rolling resistance, and comfort. The average aerodynamic advantage.
The new rims are higher, wider, lighter, and more aerodynamic. The new hubs and spokes fit together in a wheel system that weighs 1410g for the 42mm, and 1495g for the 57mm version.
4000 hours of testing across wind tunnels, labs, and the open road have resulted in the Speed 42 and 57. Seven versions of the rims, in multiple configurations, were tested to obtain the best performance for aerodynamics, rolling resistance, lightness, and handling - without compromising safety.
The average aerodynamic advantage measured in the wind tunnel with the wind blowing from the front has been increased by 10%.
Despite the higher profile, Fulcrum has managed to improve handling too by researching and perfecting a formula that considers energy dissipation in direction changes and the flexural deformation due to roll and inclines. Fulcrum says there's an improvement of 17% compared to previous generations.
The rims are constructed with a new composite mix of FF100 high modulas unidirectional fibers and resins made to Fulcrum specifications. Through multiple experiments, Fulcrum has found the “perfect mix” which combined with their “precise control” of resin, results in a product guaranteeing hors catégorie performance and a superior ride feel.
Fulcrum’s DRSC™ (Directional Rim-Spoke Coupling) system provides even greater stiffness and durability, distributing stress over a wider area that avoids chances of galvanic corrosion.
C-LUX™ technology provides the internal finish of the channel, ensuring an easy and optimal mounting for seating the tire, and the external rim is finished with DIMF (Direct Inmold Matt Finish) technology in a matte finish resulting in a surface that can easily be lasered directly onto.
Fulcrum has redesigned the graphics too, reflecting the “Form, Function, Fulcrum” identity, with minimal and refined design the goal, including new icons displaying technical information
For Speed 42 and 57, 24 aerodynamic flat spokes, Ø 2/1,6/2 mm and 2/1,7/2 mm, have been used specifically and laced with the Two-to-One™ system, which doubles the spokes in the areas subject to greater mechanical stresses.
The spokes are aligned between the hub and the rim so that they never touch, to improve performance and increase the life of the wheel.
The front wheel has 16 spokes on the disc side and 8 on the other side, whilst the rear wheel is built in the opposite way to contrast the forces developed by the transmission.
This construction provides the wheels with the torsional stiffness required to ensure the maximum transfer of power. Considering the flexural deformation and the torsional deformation based on the translation, rolling, and inclination energies, the new rims achieve a 10% improvement compared to the previous generation.
The hubs have been completely redesigned to house a more precise and lighter freewheel mechanism than the previous version.
The size of the flanges has been reduced by 40% and the central body by 10%, compared to the previous generation, giving the wheel greater resistance with lower aerodynamic drag, without giving up torsional stiffness.
The bearings used in the Speed 42 and 57 are cup and cone and use the USB™ system (Ceramic Ultra Smooth Bearings) that provides “unparalleled levels of smoothness”.
The hub system uses an aircraft-grade aluminum axle, which allows it to work with centesimal tolerances guaranteeing performance and durability.
The ratchet system of the freewheel has been reinforced and increased in size so that now it houses 36 teeth. The wheel is available with Campagnolo N3W, Shimano HG, and Sram XDR freewheel bodies.
The Speed 42 is available now, and the Speed 57 is due for release in June 2023 both cost ≈ NTD$83,000 (USD$2692).