The 303 NSW has been superseded by the new 353 NSW – and that means Zipp’s Sawtooth rim shape is back.
It’s a radical departure from the 303, with the 353 adopting the humpback whale-inspired shape that debuted in 2016 on the 454 NSW. Beyond that, however, it’s the lightest clincher disc wheelset Zipp has ever produced, with a claimed weight of 1,255g, and the hookless rim is optimised for 28mm tyres.
Zipp’s new 353 NSW | What you need to know
- At a claimed 1,255g, these are the lightest clincher disc wheels Zipp has produced
- The hookless rim is optimised for 28mm tyres
- The new Axial Clutch V2 rear hub is apparently the lowest friction hub Zipp has made
- NSW stands for ‘Nest Speed Works’ – Zipp’s engineering studio at its Indianapolis HQ
- The sawtooth rim shape was inspired by tubercles found on the fins of a humpback whale
The wavy inner edge of the rim shape – which Zipp terms ‘Hyperfoil nodes’ – is designed to act like a deeper rim (45mm deep, like the 303), while reducing the sidewall profile and behaving in a more stable manner under high crosswinds.
The shape is enhanced by the ‘hexfin ABLC simple patterning’. What’s that? For years, Zipp has used dimpled sidewalls to aid aerodynamics, but with this waved rim, the dimples vary in size and are arranged in strips that lead off from the taller sections of the rim.
Zipp claims this pattern aids both crosswind stability and aerodynamic performance.
It’s not all about aero anymore
Zipp was one of the original innovators of pure aerodynamic performance in wheels. The original Firecrest design – with its blunter, rounded profile – helped set the benchmark for aero rim design, and it’s hard to find any wheel on the market right now that doesn’t owe a debt to the Firecrest.
Now, however, Zipp puts emphasis on making a wheel that’s more (excuse the pun) rounded in performance terms. Zipp sees this as a balancing act between aerodynamics, gravity, rolling resistance and vibration losses.
Aerodynamic performance is a key part of any speed-focussed wheel design, but it’s most apparent for flatline speed, sprints and time trial/triathlon. For the 353 NSW, which Zipp classifies as a premium endurance wheel, aero performance has less priority.
It’s the gravity element where Zipp sees big gains for the 353, so it was key to getting the weight as low as possible and, at a claimed 580g for the front and 675g for the rear, these NSW wheels are the lightest clincher disc wheels Zipp has ever made. Lighter even than the new 303 Firecrest by 100g.
The set we’ve received for testing has tubeless valves, 12mm endcaps, an XDR freehub body and tubeless tape in place. The front weighs 600g and the rear 704g, adding up to 1,304g for the pair, which still makes them lighter than the 303 Firecrest by 51g.
Like the 303, weight has been saved by moving to a hookless rim design. By switching to a rim shape that’s simpler to manufacture, Zipp says it can make the rims lighter and stronger, and with less waste.
For rims with a hook, silicone mandrill is used in the moulding process to create the lip. These silicone pieces can only be used once and then the rim requires plenty of finishing, which leads to waste carbon.
With hookless designs, the moulds are solid metal and can be used thousands of times, plus the rim comes out of the mould in a near-finished state, so there’s less waste. However, if you have a hookless rim, you need to make sure your tubeless tyre is compatible with hookless.
Zipp also says the rim is optimised for the wide tyres popular on the latest road bikes. The 25mm internal width is recommended for 28mm tyres and above.
Meanwhile, the Cognition Axial Clutch V2 rear hub uses the same principle as the original Cognition hub – when it freewheels, the freehub is pushed apart to disengage by opposing magnets.
The freehub engages at 54 points and Zipp claims the new hub reduces friction and engages/disengages much faster than the already impressive Cognition design. Zipp also states it’s upped the quality of the bearings and reduced weight here, too.
The wheels are laced with 24 spokes front and rear (regular metal spokes rather than anything too complicated), with the lay-up of carbon fibre in the rim adding some vibration absorption, according to Zipp. This, paired with the wider rim width and compatibility with wider tyres, should help things roll smoothly, according to Zipp.
The 303 family
The 353s are the last piece of the puzzle for Zipp’s ever-popular all-rounder series, meaning the company now has the 303s, 303 Firecrest and the 353 NSW.
- Weight: 1,530g
- Hubset: 76/176
- Rim width: 23mm
- Recommended tyre: 25mm
- Price: £985 / $1300 / €1100
- Weight: 1,352g
- Hubset: ZR1
- Rim width: 25mm
- Recommended tyre: 28mm+
- Price: £1600 / $1900 / €1800
- Weight: 1,255g
- Hubset: Cognition
- Rim width: 25mm
- Recommended tyre: 28mm+
- Price: £3200 / $4000 / €3600
Prices and availability
The new 353 NSWs should be in stores now, priced at £1,425 / $1,800 / €1,600 for the front wheel and £1,775 / $2,200 / €2,000 for the rear wheel, with either a Shimano/SRAM 11 freehub or XDR hub (Campagnolo freehubs are available separately).
We’ve received a test set of 353 NSWs, so expect a full review this summer.