Zipp 404 NSW: faster, more stable and coasting on magnets

Zipp 404 NSW: faster, more stable and coasting on magnets

Magnetic freehub design replaces traditional springs and pawls

Warren Rossiter / Immediate Media

Published: February 1, 2016 at 2:00 pm

After Zipp’s 'Nest' skunk works churned out the Zipp 808 NSW wheelset that was ridden to world championships at Ironman and the UCI women’s team time trial, the 808's technology is now coming to the 58mm Zipp 404.

The Nest operation inside Zipp’s Indianapolis facility in Indiana, USA, is capable of making everything from rapid prototypes to full ride-ready wheelsets. The NSW designation stands for Nest Speed Works.

While the 808 is very much a specialist wheelset for TT and tri duties, the 404 is more of road racing wheel. The new NSW variant offers plenty of compelling reasons to consider it over the groundbreaking Firecrest, and the Firecrest-on-steroids that is the limited edition Firestrike.

Zipp 404 NSW specs

  • $3,100 / €2,800 / £2,150 / AU$TBC
  • 1,555g (claimed), with 
705g front and 850g rear 

  • 58mm wheel depth 

  • 27.8mm max width 

  • 26.44mm brake track width 

  • 18 front and 24 rear spokes 

  • New Cognition hubset 

The new 404 nsw is the latest project from zipp's nest design team:

The 404 NSWs come with Zipp Tangente titanium skewers
, Zipp valve extenders by Silca
, Zipp individual wheel bag
s, Zipp Tangente Platinum Pro Evo brake pads, Zipp Tangente tubes 700c x 20-28mm, and Zipp 700c x 20mm rim tapes

First up, Zipp decreased the side forces from crosswinds by a claimed 34% over the already impressive Firecrest design. The company did this via no fewer than 42 different CFD (computational fluid dynamics) studies backed up with weeks of wind-tunnel and real-world testing.

Results were achieved by reworking the rim’s surface. Zipp’s signature dimple design has been re-patterned with 12 nodes designed to start aerodynamic shearing – aiding crosswind stability – at a rate of 50Hz at a rider speed of 20mph, well within the grasp of mere mortals as well as super fit pro riders. The dimples work by keeping 'vortex shedding', the rate at which air sheds off the wheel, in control.

The less disruptive air path means a more balanced rim between the exposed and shielded sides, meaning the rim works more consistently at higher yaw angles (the angle of the wind), hugely improving crosswind stability. So the theory is you’ll be putting more of your precious watts into moving forward rather than trying to hold your line in poor wind conditions. Zipp calls the design ABLC Sawtooth.

Dot matrix style graphics keep the nsw's looking suitably subtle:

In place of stickers, ZIpp has a direct-printed logo style the company calls impress

Second, Zipp completely changed the hub design for the NSW. The new magnet-based Cognition hubset debuted on the 808 and was designed to reduce friction while coasting – meaning a faster wheelset.

Zipp’s engineering team believes that a conventional freehub designs ratchet mechanism with springs and pawls exerts a lot of friction when coasting, acting like a mild drum brake and slowing you down. The Cognition design disengages the ratchet mechanism with magnets when you are coasting. Inside the hub, a pair of metal ratchet rings instantly engage when you pedal (with the same 36 points of engagement as previous Zipp hubs), but magnets force the two pieces apart when you coast.

An added bonus is that the system requires no lubrication, and only a light oil is used inside the hub instead of grease.

The design is also low profile compared with a standard setup, so you can use a SRAM XD driver should you want to use SRAM’s wide-range 1x gearing setup, which goes down to a 10-tooth cog.

The low-profile shape of the new hubs' internals means you can swith from a standard freehub to the 1x specific xd driver:

The new hubs feature factory-set preload bearings that require no adjustment and are lighter than Zipp’s previous hubs, tipping the scales at 110g and 225g for the front and rear respectively.

Finally, Zipp has incorporated the latest brake track from the Firestrikes, called Showstopper. This combines a deeper brake track section with a siped pattern, and uses a silicon carbide material that Zipp claims improves power, modulation and heat management. We’ve used the Firestrikes in the rain and the dry, so if the NSW’s match their performance we expect to be suitably impressed.

The original Firecrests weighed in at 1,690g, with the Firestrikes at 1,620g. The NSWs come in at a claimed 1,555g for the wheelset (excluding rim strips and skewers) making them – as you’d expect – the lightest of the bunch. Price-wise they sit between the recently reduced price 404 Firecrests and the still-new Firestrikes.

The new Zipp 404 NSW carbon clinchers are available now.