Move over, 202, there’s a new lightweight crown jewel of the Zipp lineup—one that’s faster and more versatile too. Today the storied wheel brand announced a new addition to its range-topping NSW line of wheels: the 353 NSW, which takes the 303 all-around wheel to a new level of performance, low weight and correspondingly high price.
353 NSW at a Glance:
- 1,255g/set claimed weight
- Sawtooth profile
- 25mm internal rim width
- Hookless rim
- 45mm depth
- Disc only
Biomimicry: Sawtooth Rim Profile comes to the 303 Level
As an NSW-level wheel, the 353 features Zipp’s patented Sawtooth rim profile, which mimics the shape of humpback whale fins to result in better airflow.
While it does result in aerodynamic benefits, the biggest speed gain with the distinctive Sawtooth profile comes not from its enhanced aerodynamic performance, but from the added stability it provides in crosswinds, allowing you to continue riding in an aerodynamic position unperturbed by strong or shifting winds. Granted, the effect will be most pronounced for an Ironman triathlete riding with the much deeper 858 NSW wheels through crosswinds, but it provides a stability benefit at the 353 level nonetheless.
Additionally, the Sawtooth profile imparts more strength to the rim design, allowing Zipp to shed some weight over the 303 Firecrest version without sacrificing durability. In fact, these wheels are rated for gravel riding.
Total System Efficiency
Zipp used to be 100 percent focused on aerodynamics, but finding new ways to cheat the wind is an increasingly fruitless pursuit—and major wheel brands are all extremely close to one another at this point. To find more speed, Zipp has had to look elsewhere. That doesn’t mean that Zipp has abandoned the wind tunnel or aerodynamic research. Rather, it’s now just one of four major things Zipp considers in its holistic approach to wheel design which it calls Total System Efficiency.
In addition to wind resistance, weight, rolling resistance and vibration losses round out those four areas of interest that play crucial rolls in how fast—and comfortable—a wheelset is.
Just as it is for the 303 Firecrest, the center of the 353 NSW’s performance is a hookless rim design. This allows for a smoother transition between the tire and the rim for enhanced aerodynamics. The Sawtooth rim profile results in additional aerodynamic benefits over the 303 Firecrest.
One of the show-stopping features of the new 353 NSW no doubt is its weight. At 1,255 grams/set (580 grams front, 675 grams rear), it becomes Zipp’s lightest clincher wheelset ever. And as of today, it is lighter than any tubular wheel currently offered by Zipp. (The 202 tubular is the only model that used to be lighter, but it has been discontinued. And with Zipp’s research showing that tubeless wheels are much faster than tubulars, it doesn’t make much sense for the brand to continue creating the glue-on style.)
Thanks to the increased strength of the Sawtooth profile, the 353 NSW manages to drop 100 grams over the already impressively light 303 Firecrest.
Zipp’s ImPress graphics—where the logos are literally printed onto the rims with what is effectively a giant ink-jet printer—help bring the weight down further compared to decals applied with adhesive. There’s a secondary benefit in that the ImPress graphics don’t block off Zipp’s famous rim-dimples like decals can, allowing the wheels to perform marginally better.
Rolling resistance has long been thought of as a tire attribute, but it is just as much dependent on rim shape. The wide 25mm internal rim width of the 353 NSW better supports tires and allows them to adopt a shorter and wider contact patch—which is faster and provides better cornering.
That running lower tire pressures on cobbled or potholed roads leads to impressive watt savings isn’t so hard to wrap your head around. When tires can absorb the impact of large road bumps rather than deflect them into the rider and constantly bump them off their course, a rider can save 40-50 watts.
But what might be more surprising is that even on the smoothest, most seemingly perfect stretch of tarmac, tubeless tires run at low pressures can still save 3-5 watts from absorbing the tiny, almost imperceptible imperfections present in every road.
The 353 NSW rims are optimized for running tubeless (quick note, they have to be run with tubeless tires, though you can still choose to use tubes instead of sealant), making them primed to take advantage of the benefits of low tire pressures.
New Cognition V2 Hubs
The 353 NSW also debuts a new generation Cognition hub, called Cognition V2. It eschews the magnets used in the previous generation to disengage the hub ratchet system while coasting, resulting in less drag. Instead, the V2 utilizes a material called Sylomer. Used as a damper in a wide variety of applications, from automotive to medical machines, this material retains its properties over time, helping the new hub be more durable and reliable, while saving some weight too.
Campagnolo riders on the new Ekar group should know that its N3W freehub standard is not currently supported by the new wheels. The older Campagnolo freehub style currently used by its 12-speed road groups is compatible, however, but is sold separately from the Shimano/SRAM or XDR freehub options that come standard.
Between the advances in the rim shape, lower weight and new hubs with less friction, the 353 NSW is no question faster than the 303 Firecrest, says Zipp. But the question is whether it’s worth it to you to pay that price.
Pricing and Availability
All these tech advancements don’t come cheap. The wheelset costs a cool $4,000 ($1,800 front, $2,200 rear), more than doubling the $1,900 price tag for the 303 Firecrest wheelset.
They’re available now, though, as with most bike components, there may be shortages right now caused by the COVID-19 pandemic.
Zipp Pares Down, Reconfigures Lineup
There are a few big changes in the Zipp lineup, with the brand cutting out now-superfluous wheels and simplifying the tiers. Perhaps the biggest change of note is the complete departure of the 202 from the lineup. No tubular version. No tubeless version. All gone. The reason for the retirement of this legacy Zipp climbing wheel is quite simple: the 353 and 303 Firecrest are so light now—while providing a holistically better ride experience—that it really makes no sense to make it anymore.
Another big departure: the 404 NSW and 808 NSW wheels. With those two wheelsets gone, the NSW moniker is now reserved solely for wheels with the Sawtooth profile—the 353, 454 and 858—which now clearly represent the cutting edge of Zipp wheels.
Zipp’s admits its product lineup had become a bit confusing in recent years, with the Firecrest level and both NSW and 454/858 NSW level wheels. This reconfiguration should change that. The 40mm-45mm depth 303 series now has three distinct levels: 303 S for entry level; the 303 Firecrest, a bread and butter mid-range choice that will likely attract the most riders; and the 353, the price-is-no-option, peak-performance wheelset. We wouldn’t be surprised to see the 58mm 404 series or 82mm 808 series get an “S” entry level version sometime down the road to round out three options for each depth, just like the 303 series.
We have a set of the 353 NSW wheels headed to our service course for a test. Stay tuned for a report on what these 1,255-gram, $4,000 wheels can do.
more information: sram.com