Zipp’s NSW program represents the pinnacle of their engineering efforts — kind of like a skunkworks program. One of the first public-facing products from NSW is the Zipp 303 NSW wheelset which features revised dimpling, optimized layup and a unique brake track aimed at improving all-weather braking.
Zipp 303 NSW Carbon Clincher Features:
- ABLC Sawtooth dimple pattern for
- Utilizes Cognition hubset with Axial Clutch
- Sapim secure-lock bladed spokes
- ImPress graphics technology
- Showstopper brake track for consistent braking
- Rims are laid up, molded, drilled and assembled in Indianapolis
- Rim depth: 45mm
- Inner width: 17.25mm
- MSRP: $1350 (front), $1750 (rear)

NSW is as good as Zipp gets
Long heralded as one of the most advanced set of hoops money can buy, Zipp has recently gone a step beyond by launching their NSW lineup consisting of the 202, 303, 404 and 808 NSW’s. All use Zipps new Cognition hubset, ImPress graphics, Showstopper brake tracks and optimized carbon layups.
Over the years, I’ve had the opportunity to ride a variety of Zipp wheelsets, but it hasn’t taken long to put the 303 NSW’s firmly into my favorite set thus far. Let’s break down the guts of Zipp’s latest.
At the heart of the 303 NSW’s is the new Cognition Hubset, which uses magnets instead of traditional springs to engage and disengage the freehub body. The goal is to allow the internal ratchet to float instead of deliver the tell-tale click, click, click of coasting. As you can imagine, that ratcheting sound can potentially rob precious watts over the course of a long race and Zipp has aimed to eliminate that bit of loss of efficiency.
The result is a bit of a different-sounding hub from the traditional. I equate it to a muted baby rattle. It’s a different sound and was odd at first, but I’ve since equated it to a smooth ride. Have a gander at the following video for a few more details on the Cognition Hubset with Axial Clutch.
Beyond the freehub, there’s more to the 303 NSW’s that’s worth mentioning. There’s the revised dimpling pattern for even better airflow, a 200 gram weight loss, ImPress graphics and Showstopper brake track. The whole kaboodle puts these 45mm deep wheels into rare territory amongst all-rounder clinchers. Unfortunately, that rare territory is reflected in the price tag, which puts these at $3100 and makes them the only wheels worthy of being hung aboard the Pinarello Dogma F8 test bike I’ve been sauntering around on for the better part of the past 5 months.

Zipp 303 NSW’s + Superbike = Bonkers fun
For starters, I did my roll-to-stop test with the Zipp 303 NSW’s and they roll quite well — just short of my all-time best Bontrager Aeolus 3 TLR D3’s. That’s only one data point, but a promising start and the best-rolling Zipp’s I’ve tested. The neighborhood roll-out was followed up with rides (long and short) all up and down the Wasatch mounted up with the Zipp Tangente Course 25 tires. At my 170 lb. rider weight, I’ve been running these at 95 psi. front and rear.
I’ve sat in the drops for miles and rolled flat terrain. I’ve powered up more lung-busting climbs than I can count, followed by demanding descents with tricky crosswinds and put the Showstopper brake track to the test with hard-braking at speed. The 303 NSW’s are easily the best all-around rim brake wheelset that I’ve tested to date.
I love how quickly the Axial Clutch responds and have gotten used to the baby rattle sound. Coasting and pedaling is smooth with instant engagement when needed. As mentioned, the entire test was aboard the Pinarello Dogma F8 with SRAM Red eTap and I couldn’t imagine a more proper wheelset for that kind of superbike. The Dogma isn’t the most compliant bike, but it is quite comfortable for climbing-friendly all-rounder. I swapped the 303 NSW’s out for a set of Zipp 30 Course wheels and it confirmed what I thought — the NSW’s do deliver a noticeably-smoother ride over a good set of alloy wheels and do feel smoother than the 202’s to me.

Crosswinds can wreak havoc on tall-profile wheelsets. This becomes particularly dicey when descending mountain roads at 40+ mph. While the 303 NSW’s are not impervious to crosswinds, they do handle them quite well without too much extra muscle. It’s windy around here and in spite of a little taller profile, I’m not missing my 202’s one bit.
Carbon brake tracks are notoriously-sketchy when wet. There’s no way to get around it. I’ve had some very scary experiences trying to stop in the rain with other carbon clinchers. The unique Showstopper brake track aims to improve wet-weather braking performance and certainly does improve stopping power. But, by no means will these stop as well in the rain as they do when dry. Dry stopping is stellar and wet stopping is certainly an improvement over standard brake tracks, but you’ll still require a longer stopping distance. Showstopper is a good improvement, but disc brakes are simply better if you find yourself riding in the rain a lot.
Certainly, the 303 NSW’s are expensive and at that price, I’m going to expect it all. The biggest beef I’ve got is the internal width (17.25mm) and inability to run tubeless. Again, I’m going to want it all if I’m spending this kind of money.
The Good
- Delivers a smooth ride
- Performs well in crosswinds
- Showstopper does improve wet braking (just don’t expect miracles)
- The near-perfect all-rounder
- Unique freehub rolls smoothly and engages in a jiffy
- Easily-serviced (thought I had no need during my test period)
- Feel fast on the flats, climbs and descents
- Knocks 200 grams off the standard 303’s
- Laser-etched graphics are far superior to stickers
The Bad
- No tubeless-compatibility
- 19 mm or wider internal width would be great
The Bottom Line: Zipp 303 NSW Carbon Clincher
Fast-rolling, quick engagement, laterally stiff, wind cheating, sexy — that’s just a few words to describe Zipp’s new 303 NSW wheelset. They are certainly superbike-worthy wheels that will perform at the highest levels no matter where or how you ride.
Buy Now: Available at CompetitiveCyclist.com
In Summary
Zipp's NSW wheelsets are built to be fast, light and market-leading. After a summer's-worth of miles aboard the 303 NSW carbon clinchers, I'm impressed. Yes, there are wider rims out there, but these are an excellent match for the current crop of rim-brake superbikes on the market.
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Lateral Stiffness
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Responsiveness
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Durability
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Braking
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Aerodynamics
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Ride Quality
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Rolling Efficiency
12 Comments
Interested to know if you’ve ridden the Enve 3.4 or 4.5 and how they compare. I’ve got a set of Enve 5.6 Disc for fast group rides in the flats of NorCal, however in the foothills and mountains the front wheel gets a little twitchy from strong crosswinds on fast descents. No problems with crosswinds at 30mph on a bunch of rides, and looking back at a recent windy ride I was confident in crosswinds up to 32-33mph on a long 6-8% down grade. Above 33mph in 10-20mph crosswinds and the front wheel was a little too twitchy for me to confidently descend. Not surprisingly, never had a problem with the stock (non aero) Bontrager Affinity Comps on 40+mph descents in the foothills or up in Sierra mountain.
The 2017 Enve 3.4s are the same price range as the 303 NSW, and vs the 303 NSW the new Enve 3.4 come either rim or disc brake, tubeless compatible, have a wider 21mm internal width, and are aero optimized for 25mm tires.
As you’ve experienced, the 5.6’s are a little tall in stiff crosswinds. I haven’t ridden the Enve’s but I have ridden the Zipp 404’s and found them to be too tall for my tastes because of the same reasons you mentioned.
I really prefer the depth of the 303’s for all-around use. They are fast in the flats and don’t get blown around in crosswinds.
I’ve seen the 3.4 Discs and the mixed-depth and extra width really set those apart. I’d have a tough time choosing between those and a set of the new Zipp 303 discs. But, again, there is a significant difference between 54mm and 45mm depth wheels when it comes to crosswinds. Plus, the dimpling on the Zipps improves that even more.
I’m interested to hear what you decide on. Keep me in the loop!
I would like a piece of advice:
I’m planning to buy carbon wheel. After a lot of reading, my choice stopped on this clincher nsw rims. Now the question is which one the 303 or 404? And finally I plan to mix them, 404 rear, 303 front. what do you think about this mixture? My idea is to have a good compromise between the inertie given by the 404 on the back and something that you can bring up (climbing) easier with the 303 on the front (and probably also better with some crosswind).
thanks for your reply
I enjoyed reading your test
Fabien
Honestly, mixing the 404/303 together would be a fantastic idea. The 404 is a little heavier (~75g), but will be a little more aero on the flats. For me, the 404 in the front is just too tall in crosswinds, so sticking with a 303 up front would be my recommendation. ENVE does that very thing with their wheelsets (mixed depth sets) and that’s also why Zipp sells the wheels separately so you can mix them up.
Do you recommend 25mm tires for the 303 nsw?
Zipp has optimized this rim shape for 25mm tires, but you could ride 28 or bigger if you wish. If maximum aero is what you seek, then yes, 25mm is your choice.
Interesting that you run those on the Dogma F8. I’m struggling for clearance with my Roval CLX 50 at 29mm wide andnthese aren’t far behind. Was trying to find a light 40-45mm profile wheel that is tubeless compatible and fits the f8 frame. I’ve to run the roval with a 23mm rear tyre and its still tight for steep out of saddle climbing
Chris… it all depends on the combination of internal rim width and tire profile. Again, not all 25mm rubber is equal either. At 17.25mm internal with Zipp 25mm tires, I had plenty of clearance on the F8. I will add that Zipp’s 25mm tires tend to be taller than say a Continental GP4000s, for example.
I’d have a look at the Reynolds Assault SLG’s, which are tubeless and might fit your bill perfectly:
https://www.feedthehabit.com/gear-reviews/2018-reynolds-assault-slg-carbon-wheelset-review/
They are great wheels.
I just got a pair of these wheels and I am having big problems with the lateral flex when I push off the saddle or if I am climbing off the saddle. I have top open the break caliper way too much so the rim does not rub side to side. The other problem I had was that for some reason the rear hub (magnetic system) disengage/engage suddenly! This has never happened to me with traditional bearing hubs systems. These wheels are very expensive and to have these issues, I am very disappointed with its performance and quality. The wheels are back to the shop where I bought them and waiting to find out what ZIPP has to say about that.
I am not happy right now and thinking that maybe I should get ENVE 4.3 or another pair of the new Bontrager Aeolus XXX 4 TLR.
Rolando… sorry to hear about your problems, but if the hubs are defective, you will certainly be taken care of. I’ve now been riding the Cognition hubset collectively for a couple of years without problems. I’ve not heard of any significant failure rates, but Keep us posted on how the repair turns out, etc.
It is a bummer to have those kinds of issues on such an expensive wheelset, but I’m confident Zipp will take care of you.
Hi Jason,
Just reading your reviews of the 303’s. I’m currently riding the Enve 3.4’s Version 2 with Gen 1 Enve Carbon Hubs. I’m getting brake rub with out of the saddle climbing with 3-4mm of pad clearance. It’s annoyed me so much that I have got rid of them. Did you ever experience any pad rub on the Zipp 303’s or hear of this?
The other option would be to try the new Enve Carbon hub with larger flanges. What your thoughts on this?
Steve
That brake rub is annoying, but I’ve opened up the rear brakes on purpose during long climbs just to avoid it. However, it shouldn’t be a thing. I didn’t experience that once with these 303 NSW’s, nor did I experience it with the latest-generation ENVE 3.4’s on the Dogma F10.
Since mostly switching to disc brakes at this point, I’ve kissed that goodbye, but brake rotors will do something similar on standing climbs.
The new ENVE hubs should help and as I said, I had no brake rub on the 3.4’s I tested last summer. The 303’s really are a great wheelset. I’d have no issues recommending them. I know Bontrager doesn’t have the cache as Zipp or ENVE, but their latest Aeolus XXX wheels are outstanding as well and worth a look.