Aerodynamicists have long been inspired by nature, with Japan’s bullet trains being designed based on a Kingfisher’s beak, and the latest aircraft having movable noses that mimic the movements of sea birds when flying into gusts. Now Zipp has taken a similar tack, taking inspiration from whales and sharks in the design of its new Zipp 454 NSW carbon clincher wheelset.
Aesthetically, the new wheels are unlike anything else on the market, with Zipp’s engineers apparently looking at how special features on a humpback whale’s pectoral fins and the texture of a shark’s skin help them glide through the water. This has resulted in wheels with an undulating rim shape that Zipp promises to be its best ever.
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There are three major innovations that are new compared to the existing 404 NSW wheels: firstly the undulating rim depth which varies between 58mm and 53mm; secondly raised strips on the sides of the rims to improve handling in gusty conditions; and finally clusters of hexagonal dimples that Zipp says helps to keep airflow attached to the rim for longer, reducing aerodynamic drag.
Out on the road, Zipp claims that this improves the wheels’ performance in all areas, with a particular improvement when it comes to performance in crosswinds, an area of weakness for many deep section wheels in the past.
According to company’s own figures, the Zipp 454 NSW wheels have a five per cent reduction in side force compared to a 60mm competitor wheel and a 15 per cent reduction in the amount of pressure you feel when riding in a crosswind. The result should be a wheel that requires less effort to keep straight and true when riding in real world conditions, and less prone to getting caught in side gusts when riding past gaps in hedgerows and side streets.
Other aspects of the wheels are unchanged from the 404 NSWs that were released last year.
The wheels still feature Zipp’s ShowStopper braking surface, which has a textured surface that the company claims outperforms not only other similar carbon wheels in wet conditions, but also aluminium brake surfaces too. Our experiences, however, are not so clear cut, and although the braking is certainly an improvement on that on older Zipp wheels, it cannot match the likes of Mavic’s Cosmic Pro Carbon SL C wheels in the rain, and makes its way through brake pads far too quickly.
Another carry-over from other wheels in the Zipp range is the Cognition hub, a design that was introduced a few years ago which from our experience has overcome the problems with premature wear that have plagued some of the company’s hubs in the past.
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All in all, the new wheelset weighs a claimed 1525g (690g for the front wheel, and 835g for the rear) putting it exactly where we’d expect a wheelset of this depth. The rim width is also the same as that of previous wheels from Zipp’s NSW range at a very wide 17mm.
The final aspect of this wheelset that we have to mention is the price, which at £3,500 is an astonishingly high figure, almost £1,700 dearer than the 404 NSWs. That makes the Zipp 454 NSWs some of the most expensive wheels on the market, with only top-end wheels from Reynolds and German carbon specialists Lightweight being more expensive.