What is it?
Profiled covers, which fit over a regular spoked wheel to convert it into an aerodynamic disc wheel.
Wheelcovers are available in Classic, Lightweight, Premium and now new Ultra lay-up. The Lightweight and Premium both offer around a 10% weight saving over the Classic, while the Premium also features a distinctive 'spread-tow' chequerboard carbon finish. The Ultra also has the chequerboard finish but boasts a further 10% weight saving over the Lightweight as well as exclusive Gold or Silver graphics. An Ultra wheelcover for a deep-rim wheel can now add less than 200g to the wheel weight.
Premium Carbon Finish
Our bold graphics suit most frame colour schemes, but if you want something more 'stealthy' or just different, we can supply them in black, grey, red, or other colours to order. The graphics can also be left off if preferred.
Ultra Wheelcover with Gold Logo
Wheelcovers are available in a number of shapes to suit frames with close-fitting, curved chainstays and seatstays, including specific frames like the Planet-X Stealth, Specialized Transition etc.
How does it work?
All the wind-tunnel tests show that a disc wheel has the lowest drag of all types. Furthermore, as the yaw angle increases (greater relative side-wind), the drag reduces even more and in some cases can become negative - like a sail driving you forwards. For this to happen, the airflow needs to stay attached on the leeward side of the disc. This happens best if the disc is lenticular (lens-shaped) rather than flat, in the same way that an aerofoil works better than a flat aircraft wing.
What can it do for me?
A flat disc is generally found in wind-tunnel tests to be worth a saving of about 30-40 seconds over a 25-mile time-trial compared with a standard road wheel. A lenticular disc or a set of wheel-covers can improve a further 5-10 seconds on that, possibly more in a stronger crosswind.
Performance estimates are based on a number of assumptions. Individual results may vary. Key assumptions are:-
Lead-time is typically about 2-3 weeks. At busy times, it may even be a bit longer. Let us know if your requirement is urgent, as we may be able to prioritise your order.
Please remember to put in details of your rim and hub combination and any other information required, especially if your frame may have clearance issues with 'fatter' profiles. Refer to previous e-mails if you have enquired earlier. (You can also add more notes if required at the Paypal page.)
We have data for the following hubs:-
Wheelcovers can be made to various depths and dishes to accommodate shallow rims up to 100mm deep rims.
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