While you can’t ascribe human emotions to inanimate objects like bike wheels, I can tell you how I feel riding them. When it comes to riding the Zipp 303 NSW carbon disc wheelset, I get a comfortable, confident thrill I don’t often experience from the performance of other wheels.

You wouldn’t think feelings like comfort and thrilling happen at the same time or that you can be confident in pushing yourself to the limits where thrills are usually found. Yet for me, someone admittedly filled with my own contradictions, I experience comfort, confidence, and thrills at the same time from the performance of this versatile carbon disc wheelset from Zipp.

Let me explain.

As to comfort, these 303 NSW carbon disc hoops combine smooth and quiet rolling with great compliance. The rear hub freewheels without even a whisper. The wheels absorb rough roads, cracks and even shallow holes with hardly a notice.

Part of that comfort probably comes from being optimized for tubeless tires. More than tubeless ready or having tubeless as part of a crazy long name – Zipp 303 NSW Carbon Clincher Tubeless Disc Brake – the rim bed has shallow, narrow channels near the outsides of the rim beds to better secure the tire beads under the rim hooks when running tubeless tires at lower pressures.

Zipp 303 NSW Carbon Disc WheelsetI set these wheels up with 25C tubed clincher tires and 25C and 28C tubeless from multiple brands. Tubed tires like the 25C Continental Grand Prix 4000S II were a bear to get off. I wouldn’t want to have a flat on the road with tubed tires on these rims unless I was riding with Scott, whose hands are the size of a bear’s.

The tubeless Schwalbe Pro One and Zipp Tangente Speed tires were easy to install and remove. If ever I needed to put a tube inside them due to a sidewall cut too big to close with sealant, it’d be an easy job.

Zipp claims these wheels test fastest in the wind tunnel with a 28mm tire. I found, however, that Zipp’s 28C Tangente Speed Road Tubeless tire, a model whose 28C and 25C sizes typically set up narrower than Schwalbe Pro One, Mavic Yksion Pro UST and other tubeless tires I recently reviewed, measured 1 mm wider than the roughly 29 mm wide rim.

Zipp’s rim shapes have obviously changed as they’ve moved to the newer and wider NSW wheels. Their tech support representatives tell me the 95% tire to rim with rule Zipp established a decade ago and other brands have followed no longer applies to the NSW rim shapes. They didn’t tell me what their new rule is though, perhaps wanting to keep that secret sauce secret. Most other leading aero wheel designers still go by the tire-narrower-than-rim-width principle and have publicly shared the aero data to confirm it.

While riding these wheels with 28C tubeless tires is supremely comfortable, I found the 25C Schwalbe Pro One tubeless tire that measures essentially the same width as the 303 NSW rim and the 25C Tangente Road Tubeless tire that measures about 2mm narrower both provide great comfort in combination with these compliant wheels.

While I spent most of my time on the roads, a couple of outings one of my fellow In The Know Cycling testers took with this 303 NSW road disc wheelset on combined paved and dirt roads showed their versatility to be better than most.

Wide rims and wide tires usually lead to good handling. The handling on these wheels was better than good. It took me to the extremes of confidence in cornering and made me darn near fearless. I never doubted them in tight turns and I pushed them as hard as I can. That was a thrill right there.

Responsive? Yes. Acceleration? Beam me up Scotty. Aero? Held my speed well. Crosswinds? Bring ’em on. Not a bother.

For me and my mere 150lb/68kg body weight, they were plenty stiff and climbed well. They also handle beautifully going fast downhill with never a worry about speed, cornering, wind or road surface.

I’m holding back final judgment on their stiffness until one of our new testers with legs twice the size of mine comes back with his report after flexing this wheelset to his max on climbs and in sprints. I’ll update this review when he does.

Beyond how this Zipp 303 NSW disc brake wheelset performed against all of these criteria, and they did as well or better than most other all-around carbon disc or rim brake wheels I’ve spent time with, I just found these a joy to ride and really looked forward to it. That was a thrill in itself.

Of course, being Zipp’s top-of-the-line carbon disc wheelset model, it’s not a cheap thrill. But if you are up for all that I experienced, you can get these wheels by clicking through to Competitive Cyclist for US/CA residents and Tredz for those living in the UK/EU.

In The Know Cycling supports you and your fellow enthusiasts by doing hours of independent and comparative analysis to find the best road cycling gear and kit to improve your riding experience.

You support us and save yourself money and time by buying anything at all through the red links to stores we’ve picked for their low prices and high customer satisfaction. These stores pay us a small commission when you buy there after clicking on these links. Thank you. 

Read more about who we are, what we do and why.


  • Thanks for the review Steve. I love the wheels, bought them based on your review of the rim versions best all-rounder, upgraded from the course 30 rims. I’ve had no problems with getting clincher tyres on or off, I’ve found them way easier with these rims, maybe because of their design, I don’t know, but definitely way easier than with the course 30’s. Zipp advised me to use 28c tyres, I used the Conti GP4000SII 28c but they didn’t last long, especially on the rear, 500-1000 km max, I’ve found the tyres to be too soft, wear and puncture easily. I noticed that Cannondale on the SystemSix are using 23c tyres on the Knot64 rims, the rim specs are similiar to the Zipp NSW 303 Disc apart from depth, so I thought I’d try Schwalbe One V-Guard 25c, bingo, slightly heavier than the Conti’s, similar rolling resistance but way more bullet proof, the 25c measures 28mm wide on the rims, with more wear they now measure about 30mm wide. Panaracer Race Light Evo 3 became available this year so I’m currently trialing them out, they are lighter than Conti and Schwalbe, more bullet proof that Scwalbe, rolling resistance isn’t as good but from my experience and feel, lighter out ways heavier with better rolling resistance. I’ve also found that 28c moves around alot especially in the rear (presumably caused by more air volume), whereas the 25c is primo, more responsive, quicker to accelerate, no movement in the rear. I’m 79 kg, 25c tyres are fitted with VittorIa latex tubes with 99.9 psi in the rear, 98.9 on the front. This setup I’ve found perfect for me and steed.

    • I’m surprised that you find Conti GP4000SII 28c to be soft. In reality, it’s overbuilt German tire. Thicker tread and puncture resistance is quite high. As much as I like these, they fall into all-season category and far from supple. On a positive note, rolling resistance is among the best. It’s good that you mentioned Panaracer Race A light EVO3. People rave how supple this tire is.

      • Yes, unfortunately maybe just me, the Conti is a great tyre but they don’t last on the rear, I have mates who use them and don’t have any issues, but unfortunately for me I’ve gone through a few and they damage easily. I’m 79 kg and run them at 99.9 psi on the rear and they are great, fast, sticky, everything, except durable. 500-1000 km is only 2-4 weeks riding. Yes, the Panaracer L Light EVO3 @ 205g that has been available earlier this year I’m now testing, I’ve used it on the front for 400 km and will move it to the back to test its durability, fingers crossed.

        • 79 kg is not heavy, so why do you run such high pressure? I keep 25mm at 80 psi and 28mm at 65 psi. Typically the root cause of punctures is over inflation.
          I have been running these tires for years, year round. As you may know Conti GP4000SII run wide, even on narrow rim. 25mm measure ~27mm with caliper and 28mm measure ~30mm.
          Panaracer Race A light EVO3 is a durable tire. As a matter of fact it’s more puncture resistant than Conti GP4000SII

          • I run them at these pressures through testing and feel, lower means too much movement when putting the power down. I started from 85 psi and moved up bit by bit till I was happy with the feedback, not too hard, not too soft for the flats and climbing. Yes http://www.bicyclerollingresistance is what I use to choose tyres. My gut feeling is the NSW303DISC rims are such in design and spec that they are not as compatible with the Contis spec as with other tyres that haven’t had the same issue.

  • Great review, can’t wait for the full update. Have you considered the new Industry 9 carbon deep disc road wheels? Could be great comparison, all mountain bikers I know have about I9.

    • Scott, I haven’t considered the i9 wheels as of yet. From what I can tell, their new wheels have Reynolds designed rims and i9 hubs. Reynolds wheels, like the Aero 46 DB I have been testing have i9 torch hubs. i9 torch hubs are also now available on some ENVE wheels. Reynolds is also likely coming out with new Attack, Assault and Strike wheels (my guess based on how few of the current model are in the pipeline, how low the prices have dropped, and how long its been since an update/redesign) and I’m curious to see how similar their rim shapes are to those of the new i9 wheels. i9s wind tunnel tests compare to Zipp 303 and 404 Firecrest disc wheels which are their second-tier wheels and likely to get an upgrade soon as the NSW rim shapes get passed down.

      All of this is not unlike DT Swiss’ long time strategy of selling their hubs to a lot of top wheelmakers (Enve included but other top brand names like Roval also using them as their hub internals) and DT is now selling wheels with rims designed by SwissSide. DT Swiss and to a lesser degree Chris King and i9 are all fighting for share for OEM wheels. Following DT, i9 are now branding their own wheels with other’s. Others like Zipp, Campy, Easton, HED still designing and building (or having built) their own hubs.

      It’s a lot to keep up with and try to separate the reality from the hype. How much of a difference do the hubs make on high-end wheels relative to the rims? Depends what performance, design and cosmetic aspects are most important to you.

      Will try to give you much of that in our full update though not including the i9 (but including the Reynolds Aero 46 DB), which I hope to finish and publish next week. Steve

Add Your Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.