Form, Function, Fulcrum?
The wheel manufacturer claims their new aero road wheels are better in every way.
The new Speed are available in two versions, with 42 mm and 57 mm profiles, which replace the previous 40 mm and 55 mm sizes, whilst the inner rim width has been increased from 19 mm to 23 mm. The nose of the rim has also been widened with a radius of 9.5 mm.
The new wider rimes are optimized for use with 28mm tires and offer best performance when setup tubeless. Fulcrum claim the average aerodynamic advantage, measured in the wind tunnel with a headwind, has been increased by 10% compared to a rim with an inner rim width of 19 mm.
Despite the higher profile, handling has been improved considerably. Fulcrum carried out a specific research project to define a formu- la that would take into account the energy dissipated by the wheel during changes in direction and the flexural deformation based on roll and inclination. The data measured confirmed that the new Speed have seen an improvement of up to 17% compared to the previous generation.
Fulcrum wheels designed for tubeless tires
Interesting is the MOMAG undrilled Carbon rim bed technology and 2-way fit tubeless technology. Hooked rims and an undrilled carbon rimbed that doesn't require rim tape are supposed to make fitting tubeless tires even easier and helps maintain same stiffness along the whole perimeter and achieve greater resistance to impacts. This is also helped by the nipple holes, which are created in the mold, without having to drill the rim like traditional wheels, which weakens the structure as it cuts the carbon fibre.
New Carbon layup for Fulcrum Speed road wheels
Fulcrum use a new composite mix of FF100 high modulus unidirectional fibres for the Speed 42 and 57. Increasing the precision of the carbon layup and optimizing the use of resin, help create a product that increases ride feel and stability while staying fairly light.
Fulcrum's own DRSC (Directional Rim-Spoke Coupling) system supposedly helps avoid galvanic corrosion and provides more durability and stiffness for the spokes. While i never tried them and cannot give a real objective opinion the idea of plastic support for the nipples is a bit frightening for me.
The finish of the Wheels looks very nice and classy. Matt finish, very stealth without any flashy colors or huge decals the wheels will attract a range of style aware performance focused users. Interesting is, that the matt finish is achieved directly in the mold. (DIMF or Direct Inmold Matt Finish)
The spokes of aero wheels
For the Speed 42 and 57 we have used 24 aerodynamic flat spokes Ø 2/1.6/2 mm and 2/1.7/2 mm, designed specifically for this wheel and laced with the Two-to-OneTM system, which doubles the spokes in the areas subject to greater mechanical stresses, to prevent the dispersion of energy and contrast the torsional force.
The front wheel therefore 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 trans- mission. This specific construction (if we assume perfect tensioning of the spokes) is claimed to provide the wheels with the torsional stiffness required to ensure the maximum transfer of power. Fulcrum names a 10% improvement in stiffness compared to the previous generation.
New proprietary hubs
Proprietary hub systems are always controversial in terms of spare parts and ease of swapping parts, however it is great to see Fulcrum push more diverse products on the market and help drive competition against behemoths such as DT Swiss. By default the hubs are built with ceramic bearings. (Or more specific Ceramic Ultra Smooth Bearings 😜)
Paired with aircraft grade aluminium axles this indicates a high quality and performant hub.
The ratchet system of the freewheel has been reinforced and increased in size so that now it houses 36 teeth. The wheel is avail- able with Campagnolo N3W, Shimano HG and Sram XDR freewheel bodies.
Specs of the Speed 42 aero road wheels
- Full carbon aero profile: 42 mm
- 23 mm inner rim width
- 2-way fitTM tubeless - undrilled rim bed • USBTM - ultra smooth ceramic bearings • Engineered in italy - made in eu
- 1,410 g
Specs of the Speed 57 aero road wheels
- Full carbon aero profile: 57 mm
- 23 mm inner rim width
- 2-way fitTM tubeless - undrilled rim bed • USBTM - ultra smooth ceramic bearings • Engineered in italy - made in eu
- 1,495 g / Combo 42/57 1460 g
