Hunt has launched the new 5AM Limitless Ti_UD Carbon Spoke wheelset, with a deeper and wider 58mm front wheel, and shallower and narrower 55mm rear wheel.
The new wheelset includes carbon spokes for a claimed 1,212g weight and Hunt says it is the fastest all-round road race wheelset it has ever tested – both its own and those from key rivals.
Both front and rear wheels have a 23mm internal-width hooked rim, but the front wheel’s maximum width is 34.5mm, while the rear’s is 30mm.
Hunt says most aero gains are achieved at the front wheel, where airflow is more laminar, while the turbulent airflow around the rear wheel makes light weight and maximum power transfer more significant.
The deep front and shallow rear design, and the thinking behind it, mirror the Roval Rapide Sprint wheelset, which was launched last year and which Hunt has used as a comparator in its wind-tunnel testing. That wheelset has a 63mm front and 58mm rear rim depth, and 1,395g claimed weight.
Hunt says its new wheels are aero optimised for the 28mm to 30mm tyre widths now chosen commonly for racing.
As with many carbon-spoked wheels, Hunt has reduced the spoke count in its new wheelset, which also helps keep weight down and reduce drag. The 15 front and 18 rear Vonoa Ti_UD carbon spokes weigh only 1.7g each and have titanium ends. The internal nipples again help to optimise airflow.
Hunt uses its patented Limitless tech in the front wheel, which moulds low-density material into the sidewall between the layers of carbon fibre to enable it to produce a more aero profile without a large increase in weight. It claims the wide, blunt rim shape improves aerodynamics at higher yaw angles and increases handling stability.
The wheels turn on Hunt’s Chase SLC aero alloy hubs with a 48-tooth ratchet freehub that provides a 7.5-degree engagement angle. There’s a choice of steel or, for a price uplift, newly designed CeramicSpeed bearings that are yet to be launched officially.
Tested against ENVE, Zipp, Scope and more
The 5AM in the new wheelset’s name doesn’t, as I had imagined, refer to the best time to start your ride, but Hunt’s Aero Maximisation process. This has five stages, starting with CFD computational analysis of airflow around the wheel and wheel-bike combination.
This is followed by three phases of aero testing in a wind tunnel, beginning with the wheel alone, moving on to wheel-plus-bike and finally wheel, bike and pedalling rider.
The fifth stage takes the wheels to a velodrome, defined road course or aerodrome runway, using an Aerosensor drag-measurement device to measure real-world parameters such as rotational drag.
Hunt has compared its wheels to seven competitor aero wheelsets in the wind tunnel. Based on its testing using 30mm Schwalbe Pro One tyres, Hunt claims its wheels are 1.74 watts faster than the Roval Rapide Sprint and 4.35 watts faster than the ENVE SES 4.5 Pro wheels used by Tadej Pogačar‘s UAE Team Emirates-XRG WorldTour team.
Hunt has also tested its wheels outdoors on a runway, where it says it found an 8.5-watt aero advantage over the Zipp 404 Firecrest and a 5.9-watt gain on the Scope Artech 6.
The 5AM Limitless Ti_UD Carbon Spoke wheelset is available with a choice of stainless steel or CeramicSpeed hybrid ceramic bearings, with the wheelset priced at £1,999 / $2,599 / €2,349 with steel bearings or £2,489 / $3,199 / €2,899 with ceramic bearings.
