Zipp launches new 454 NSW, 404 Firecrest, and 858 NSW go-fast aero wheels
Zipp launches new 454 NSW, 404 Firecrest, and 858 NSW go-fast aero wheels
Zipp’s latest generation of wheels — the 353 NSW, the 303 Firecrest, and the 303-S — have all featured aero shapes, but they’ve also been very progressively wide, disc-brake-only, and tubeless-only. Now joining that trio are three new models that follow in the same vein: the 454 NSW, the 404 Firecrest, and the 858 NSW.
The second-generation 454 NSW is slower, but faster
The new 454 NSW Tubeless Disc-Brake wheels (yes, that’s the official name) are designed to be the ideal all-rounder for road, paved or otherwise — if you could only afford one model in the Zipp family for your high-performance drop-bar bike, this would be it.
Although this wheel shares its model name with the original 454 NSW, there’s not a whole lot of resemblance. The new rim still features a sawtooth-like rim profile with an undulating 53-to-58 mm depth that Zipp still claims to offer superior crosswind stability as compared to a more conventional design (and based on my anecdotal experience with the older 454 NSW and similar wheels from Princeton Carbon, I’m inclined to agree). However the new rim is a whole lot wider with a 23 mm internal width, and the clincher version is now tubeless-only – and disc-only – with a hookless tire bed.
Despite the inflated dimensions, it’s also more than 250 g lighter with a claimed weight of just 1,358 g (631 g front, 727 g rear, without tubeless rim tape but with SRAM XDR driver body).
Zipp laces this rim to its updated Cognition V2 disc-brake hubs. The old magnetic pawl system of the original Cognition driver mechanism has been replaced with a “Sylomer” polymer leaf spring design, which Zipp claims to not only be 10 g lighter, but spins with “23% lower coasting friction” and offers faster engagement (6.67° vs. 10°) to boot. Zipp doesn’t make any mention of this, but the simpler design also uses a lot fewer parts and will likely be more reliable, too.
Zipp may be looking at more than just aerodynamic efficiency in its road wheels these days, but the company’s primary focus in this area is still figuring out how riders can eke out more speed from the same output, and to that end, the 454 NSW is certainly claimed to be a whole lot faster than the previous version. As compared to the original 454 NSW, the new one will supposedly save 10 watts of effort when traveling at 40 km/h (which, in all honesty, is a pretty attainable speed, even for a solo rider of fairly average fitness).
Interestingly, that improvement is despite the wheels actually being more than 3 W slower when viewed purely in terms of aerodynamic efficiency when tested with the same 25 mm (printed width) tires; all of the overall speed gains are coming from rolling resistance and weight improvements.
Retail price for the Zipp 454 NSW is US$4,000 / AU$6,027 / £3,200 / €3,600.
Just to be clear, there is no rim-brake model for the new 454 NSW. However, SRAM has added a tubular version with the same undulating 58/53 mm rim profile and updated Cognition V2 hubset to satisfy its sponsored teams and athletes. Interestingly, though, claimed weight on the tubular version is actually 105 g heavier than the tubeless clincher version at 1,463 g.
New 404 Firecrest follows in the footsteps of the 303 Firecrest
Following the lead of Zipp’s versatile 303 Firecrest model, the new 404 Firecrest Tubeless Disc-Brake wheelset looks beyond just aerodynamic performance with a new focus on rolling efficiency and reduced weight. Rim depth remains the same at 58 mm, but the newly hookless internal width grows from 19 mm to 23 mm, and the external width is slightly more generous at 27.5 mm. Like nearly all of Zipp’s latest generation of road wheels, the 404 Firecrest is also disc-brake-only and tubeless clincher only.
As with the new 454 NSW, the revamped 404 Firecrest is less aerodynamically efficient than the current version (although, in this case, the claimed difference is just 0.9 W). However, the rolling efficiency gains that come with that broader internal rim width (and lower recommended inflation pressures) nevertheless give the new 404 Firecrest a 4 W total saving for an 85 kg rider (including bike) traveling at 40 km/h.
Speaking of aerodynamics, it’s worth noting that although Zipp says the new 454 NSW and 404 Firecrest are both optimized for a 25 mm (printed width) tires, and if you abide by the “105% rule“, you won’t want to go any wider than 26 mm. As such, these are very much intended for road use, not gravel (although they’d probably work just fine if you’re so inclined).
The new hookless design does lop off a lot of mass, though. Actual weight for a set of 404 Firecrests is 1,508 g (691 g front, 817 g rear, with tubeless tape and a SRAM XDR driver body) — a saving of about 370 g.
Anchoring the new 404 Firecrest wheels is Zipp’s new “engineered in Germany” ZR1 DB hubset, which the company says incorporates updated seals for improved all-weather durability, plus a new six-pawl drive mechanism that offers a speedier 5.5° engagement speed.
Although the 404 Firecrest may not be quite as efficient, light, or neat-looking as the 454 NSW, it sure is a heck of a lot less expensive. Retail price is a comparative bargain at US$1,900 / AU$2,863 / £1,600 / €1,800.
A note on Zipp’s wild-sounding rolling efficiency claims
The claimed improvements to rolling resistance for the new 454 NSW and 404 Firecrest almost seem too good to be true, but without independently verifying them myself, I can only report them as “claimed” figures for now. That said, I did request further clarification on how exactly Zipp arrived at those numbers.
“The tire pressures were set by the AXS tire pressure app,” said Zipp product manager Nathan Schickel. “Each wheel’s pressure was set according to the individual specs for the rider, wheel, and tire. Previous model 404 Firecrest and 454 NSW wheels are 19 mm internal hooked [and the rim-brake 454 NSW was 17 mm — Ed.] and the new wheels are 23 mm internal hookless. All wheels ran the Zipp RT25 tire. The older wheels were run at 77 psi front and 82 psi rear. The new wheels were run at 65 psi front and 69 psi rear, again the appropriate tire pressures for the given tire/rim system.”
In other words, the new wheels’ more generous internal rim widths likely afford some rolling resistance improvements on their own, but more so in the sense of how they allow for lower inflation pressures that are better able to conform to less-than-ideal tarmac without incurring frictional losses.
Tri- and TT-focused 858 NSW gets a hub update
Last but not least, Zipp’s most aggressive 858 NSW carries on with the same 77/82 mm undulating rim depth, 18 mm internal width, hooked rim profile, and tubeless clincher compatibility as the current model, but now with the same updated Cognition V2 hubset as the new 454 NSW.
Claimed weight is 1,773 g (838 g front, 935 g rear, without rim tape, with SRAM XDR driver body). Retail price is US$4,400 / AU$TBC / £3,930 / €4,400.
All of Zipp’s new carbon wheelsets are supposedly available now, and also include the company’s latest lifetime warranty policy, which covers the original owner for “damage during intended use per the user manual, as well as defects in materials or workmanship, for the lifetime of the product.”
Reviews pending
Zipp sent samples of the new 404 Firecrest ahead of the official release date, but I’ve only ridden them enough for some initial impressions — and truth be told, it’s all quite favorable at the moment. Tests will be ramping up in earnest in the coming weeks, though, so stay tuned for a more complete report shortly.
For more information, visit www.zipp.com.
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