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The new Zipp 303 S and Zipp 303 Firecrest road disc wheelsets have raised a lot of questions and a fair amount of concern among fellow road cycling enthusiasts.

The questions start with what’s new about these wheelsets and how they perform on the road. The concerns center on what these introductions might mean to the bike and gear purchase decisions we’ve recently made or are planning.

In this post, I hope to answer some of these questions and put the new Zipp wheelsets into the context of the party that’s going on now with a broad group of new, even wider road and gravel wheelsets.

What’s new about Zipp 303 road disc wheelsets

Hookless rims are the essence of what’s new about the new Zipp 303 S and 303 Firecrest road disc wheelsets.

By going hookless, Zipp claims they’ve produced lighter rims with wider inside dimensions that are less costly to produce and will make the wheels faster and more comfortable and suitable for both paved and gravel roads compared to the models are replacing.

That’s a long sentence. Let me break it down. It’s kind of dry, as a description of design specs rather than a review of actual performance can be, but hang in there with me and I hope to make it worth your time.

Hooks are those 1.5mm or so wide protrusions extending out from the inside rim walls that a tire bead locks into when you inflate it. A rim without hooks will automatically start with a 3mm bigger inside width and weigh less than a rim with them. Kind of obvious.

Wider, lighter, less costly, faster, and more comfortable are all comparative words. Zipp is comparing the 303 S to the 302 road disc wheelset model it replaces and the 303 Firecrest to its same-named predecessor.

The 302 had a stock wheel-like actual weight over 1750 grams and used first-generation (circa the early 2010s), non-tubeless 303 Firecrest rims (without dimples) that had a 16.2mm inside and 26.0mm outside width. They were fast when you got them up to aero speeds but not very responsive or comfortable in contrast to today’s better wheels. The 302 sold for US$1500.

Compared to the 302, the 303 S is indeed lighter (measured 1556g) and wider (measured 22.5mm inside, 27.5mm outside). They sell for $200 less at US$1300 (€1,100/£985).

You can read my review of the 303 S here and the 303 Firecrest here.

The last 303 Firecrest used earlier generation 303 NSW rims that were Zipp’s first tubeless disc brake models. They were as wide (21mm and 28mm) as most of their road disc wheelset competitors are currently and, at 1632g, were in that hard-to-tell-on-the-road heavier weight range (75-175g). Their full price was US$2300.

I measured the new 303 Firecrest wheels at 25mm internal and 30mm external width and 1383g. Their price is US$1900 (€1,800/£1,600) or $400 less than the previous Firecrest model.

The new 303 Firecrest wheelset is also considerably lighter and wider than the earlier model. They are also shallower, now 40mm deep vs. the prior generation’s 45mm depth.

The 303 S hubs are the same as those used on the 302 wheels while the ones one the new 303 Firecrest are new for the company. Zipp seems to introduce a new hub with a new design every year or so and now has three very different ones in use across their 303 and other wheelsets lines.

I’m not saying it is good or bad to regularly introduce new hubs, it’s just a challenge to understand what’s different and more importantly, predict how they’ll perform over time.

Zipp has also “moved the goalposts” or perhaps is playing on a new field in how they measure and create speed and comfort with their new 303 wheelsets. Without getting into or debating the details of their new approach, let’s just say it looks like they’ve moved out of the wind tunnel and are trying to get closer to the “real world.”

Since the real world is where the paved and gravel roads are that we cycling enthusiasts ride, it’s a step in the right direction. Until you dig into it, however, Zipp’s new approach does look like a lot of marketing hooey.

The other “new” thing about Zipp’s 303 line is that they will stop making the 303 NSW disc brake wheelset at the end of June while continuing to make unchanged versions of the 303 NSW and 303 Firecrest rim brake models, save for a logo facelift. I’ve not seen nor have an explanation other than to conclude this is further evidence of the increasingly disconnected worlds of road disc and rim brake wheelsets.

With the 303 NSW disc brake wheelset gone, Zipp has effectively dropped the price of their best wheelset for the largest performance-oriented carbon disc aftermarket category (all-around) by 40% from US$3200 for the former 303 NSW to $1900 for the new 303 Firecrest. That’s a big drop in price and perhaps, a big performance hole in their lineup.

Other than updating the logo across the board and putting the new ZR1 DB hubs on their 202 and 404 Firecrest wheels, Zipp is not making any changes to their other wheelset lines, at least not for now.

While I have no inside information, I suspect Zipp will discontinue other higher-priced disc brake models, make fewer rim brake models at all price points, add more lower-priced “S” ones, and update the 202 and 404 Firecrest wheelsets to hookless over the next year or so.

My analysis below will hopefully shed some light on why I expect these further developments from Zipp.

Putting Zipp’s new wheels into context

While the new 303 wheelsets and line changes may seem shocking in light of Zipp’s position in the carbon wheelset movement they helped create, in reality, they are following or joining other well-established road wheelset brands and models on a similar path.

ENVE was one of the first to the hookless, even wider road rim party in 2016 with the 25C wide SES 4.5 AR, a 50mm deep front, 55mm deep rear wheelset. They added the SES 3.4 AR in early 2019, a wheelset whose width, depth, and weight the Zipp 303 Firecrest matched but whose price Zipp beat.

The MTB wheel and tubeless sealant maker Stan’s No Tubes makes the Avion Team road disc wheelset that shares similar specs to the 303 S – hookless, 22C wide, 42mm deep, 1500 grams, carbon road disc – except the Avion was introduced in 2016.

Until recently ENVE and Stan’s have had little company in the even wider and, in some cases also hookless rim party.

In alphabetical order, the 3T Discuss C45, Bontrager Aeolus Pro 3V, DT Swiss GRC 1400 Spine 42, and Reynolds ATR carbon disc wheelsets joined the festivities last year with rims in the same 23-25mm inside width, 35-45mm deep range rim as the newly introduced 303 S and 303 Firecrest. They are all targeted to those who want a wheelset that will work on both paved and gravel roads.

Just as wide though shallower, the Easton EC90 AX, Hed Eroica Carbon, Mavic Allroad Pro Carbon SL, Roval Terra CLX, and any number of wheelsets from lesser-known brands are all being made for the multi-surface road rider.

Most in the first group are heavier than the Firecrest or 3.4 AR but some are just as light and most are also less expensive. Those in the second, shallower group are mostly as light and less expensive. None but the Hed Eroica Carbon are also hookless.

We are testing a cross-section of those wheelsets now. The post at this link describes all the wheels we are testing now.

ENVE also introduced two hookless 21C models this year – the ENVE 45 (review here) and ENVE 65 (review here) that are priced halfway between the 303 Firecrest and 303 S.

So Zipp is joining the party fashionably late but has entered with quite a big media entourage in tow. Hopefully, they will keep things popping.

What it all means

We road cycling enthusiasts are hosting and paying for this wheelset party. And as hosts, we are addressing and welcoming our guests to come with the following spirit.

PriceYour wheelset prices have to come down. Have you seen how many cyclists are willing to take a chance on $1000 carbon wheelsets from brands with little if any track record and useless warranties that way underperform the $2000+ wheelsets you’ve been offering us for years?

Last summer I reviewed over a dozen wheels for my “best carbon wheelsets for the money” posts (Part 1 and Part 2) in the $1000-$1500 range. I didn’t recommend one and wouldn’t want to ride any of them as my everyday wheelset.

That is changing as the established, integrated wheel brands introduce new wheelsets with better performance and warranties. There are at least two new ones I’ll be recommending and posting reviews of soon. Not world beaters but worthy values.

ComfortRegardless of price and performance criteria, ample comfort must be built-in or enabled in every wheelset. Comfort is now a table stake and leads to a binary choice. If we can’t be comfortable riding your wheelset, it’s not going to sell very well.

At first, it was mostly about the tires. We moved from 23C to 25C tires and dropped the pressure. For many, it didn’t matter if added comfort slowed us down (aero effects of tires wider than rims; rolling resistance increases or changes little depending on how far you lower your psi) or affected our handling (somewhere between better or worse, again depending on pressure). More comfort made us feel better on the bike and studies soon followed showing how much less energy we expended (and watts we saved) rolling more comfortably.

Wheelmakers have also gotten behind making all their rims at least tubeless-ready recognizing you can more safely set their pressure at a lower level to make your ride more comfortable. Unlike with tubeless tires, when you lower the pressure with tubed-tires you increase the likelihood of getting a pinch flat to the point where you just won’t want to ride with tubes anymore.

As otherwise sane cyclists have started putting 28C tires on any wheel that rolls, most sacrificing aero and often handling performance in the process, wheelset makers have been working to provide new wheelsets that offer comfort and better aero and handling performance.

Wider tires on wheels with larger inside rim widths (from 17C to 19C on rim brake wheels and 19C to 21C and now to 23C and 25C or road disc ones) give your tires better support in handling maneuvers. Those same wider tires, even 28C ones mounted on wheels with outside widths now hovering around 30-32mm, give you better aerodynamic performance too.

Removing the hooks as ENVE, Zipp, and HED have done improves the handling and aero performance even more.

Collaboration For any of your tire and wheelset developments to work well, you need to party together. We still don’t have a standard for fit and size to guide the tubeless tire and wheelset makers and those of us enthusiasts who buy, mount, inflate, seal, and ride your products.

The result is that some tubeless tires and wheels get along famously and others just don’t. I’ve written a lot about that before (such as here and here) and don’t want to revisit it now.

Hookless adds another dimension of uncertainty or, at best, unknowing. ENVE publishes a list of tubeless tires they’ve tested and say are compatible with their hookless rims and another shorter list that isn’t. Zipp hasn’t published a list of tires compatible with their new hookless rims but claims any tubeless tire will work with their new 303 S and Firecrest.

Continental, which makes the highly-rated Grand Prix 5000 TL that ENVE has rated incompatible with hookless rims, says none of their road tubeless (or tubed tires) should be ridden on hookless rims. For now, I’m following the ENVE list when I ride hookless rims from any wheelset company.

Most wider hooked rims ride more comfortably and handle better with appropriately pressured tubeless tires compared to their tubed-tire counterparts. Yet, a majority of us roadies still prefer tubed tires primarily because of the standard-less inconsistencies around tubeless tires and the years of experience we have changing a tube after getting a flat out on the road.

One answer some are offering to deal with this seems wrong to me. Use a tubeless tire they say, just ride it with a tube instead of sealant inside. Easier to mount and replace if you get a flat.

Yet, as you lower the pressure on your 28C tire into the 70psi, 60psi or 50psi range recommended for the combination of wide tires, wide rims, optimum comfort, and improved handling, you’ll be changing your tubes a whole lot more often from the increased number of pinch flats you’ll get at those low pressures than you ever would from a sidewall tear on a tubeless tire. And when you aren’t flatting, using a tube inside a tubeless tire also increases weight and rolling resistance.

I hold the view that a tube inside a tubeless tire is a “break-glass in an emergency” solution on the road and not a good excuse for learning how to mount and seal a tubeless tire.

Oh, and yes, when we’re talking about better collaboration, let’s not ignore the bikes you want to ride these wider wheels and tires on. How many of you have frames with 38 to 40mm chainstay, seatstay, and fork openings that will fit a 30mm or 32mm wide rim or its 28C inflated tire plus the added 3-4mm either side of the tire to allow for deflection?

Most rim brake bikes don’t and older disc brake ones (like 2-3 years old) don’t either. How many of you even know what your opening widths are? The bike frame supplier dudes need to keep up with the even wider rim and tire trendsetters or this party is going to fizzle out pretty quickly.

Inclusiveness Most of us like to try out new things from time to time. Sometimes we are forced to. We want some fresh kit or our tires wear out. We are intrigued by those new wheels you are publicizing and are thinking about trying some mixed surface riding with all the hype you’ve created around it. Some of us are retro grouches but many are also into doing new things. Lots of them. So please make it easy to include all of our preferences in what you are doing.

Whether you’ve checked it out or not, gravel cycling is fast-growing. It’s a nice change of pace, a bit safer than riding the roads all the time and has a cooler vibe surrounding it than the road racing scene or aging gran fondo one.

Wheelset makers are clearly getting behind gravel, increasingly with multi-purpose wheels that can be used on both gravel and paved roads. I listed a bunch above.

The idea of mounting up different tires on a single wheelset that can be used on the road, gravel, or a combination of both on the same ride is cost-effective and inclusive for sure. Time will tell whether they also provide good performance on each surface or a compromise that leaves you wanting more.

Differences At the same time some of us look for our wheelsets to do more, others of us appear to have needs that are even more different from one to the next. Give us enough options to serve our different preferences. 

Some of us like stealthy, blacked-out wheels with barely visible logos whereas others are attracted to the ability to personalize rims and hubs with colors and patterns that declare our identities.

Those looking for dedicated climbing or aero or all-around wheels continue to separate themselves from each other. More people are still riding tubed tires than tubeless ones and while road disc bikes are outselling rim brake ones, there are still more of the later on the roads.

The biggest difference within which all the others seem to fit right now is what I’ll call the performance-focused and value-conscious riders. These two groups have always been out there but most of the proven carbon wheelset brands have historically ignored the value-conscious crowd until recently.

Performance-focused wheelset buyers are willing to pay $2500 and up for top-rated aero performance, premium lateral stiffness, the smoothest rolling bearings, exceptional handling, minimal crosswind performance, and the lightest weight possible. More than average comfort and competitive pricing are at the bottom of the list for these buyers.

Value-conscious enthusiasts care about low prices first and foremost with specs that can make them feel they are getting a good performing wheelset even if they aren’t getting any higher performance level than the price would suggest. Being able to use 28C tires for better comfort despite their negative impact on aerodynamics and handling is also key for this group. Aero performance, hub sound, stiffness, tubeless, warranties, company experience and reputation aren’t priorities that affect their buying decision.

We went through a period when wheel rims were mostly made of aluminum alloy to one where they were either alloy or carbon. Now, most enthusiast-level wheels you can buy that would be an upgrade over the ones that came with your bike have carbon rims.

During this current carbon rim period, we’ve seen a stratification of $2000-$3000 (and up) wheelsets for the performance-focused buyer from known brands with integrated design, manufacturing, and sales & support operations and $1500-$1000 (and down) wheels for value-conscious riders from new brands which principally source and sell or those with little brand presence that largely manufacture wheels.

Reynolds has been a notable exception, for years making both a line of performance-focused wheels and another group of value-conscious ones.

What is perhaps most exciting about the Zipp 303 S at $1300, another you’ll soon see from Bontrager, and to lesser degrees, the ENVE Foundation 45 and 65 ($1600) and 303 Firecrest ($1900) is that more of the established brands are putting their integrated effort and extended warranties behind making wheels for value-conscious enthusiasts while others are coming up with wheels that fit somewhere between the two groups.

That makes this party host smile and ready for another drink, eh … test ride.

Stay well my friends,


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  • Nick Mannerings

    Let’s be clear here. Non tubeless tyres should not be used on hookless rims. Especially at pressures many of us like to use with tubes.

    This could prove dangerous for some as the scope for misuse is made easier.

  • How does the campy wto 45 fit in this conversation?

    Thanks Nolan

    • Nolan, It doesn’t. It’s an all-round dedicated road wheel with a 19mm inside and 26.5mm outside width, comparatively narrow for road disc wheels these days that would be best suited for 25C tires. It has a beautiful finish I’d never want to ride offroad for fear of dinging it. It also sells for around $2000. Steve

  • Great article Steve, Sums up perfectly where I am. I don’t really want Tubeless, because of the Faff (How long will my mates in the club wait, whilst I’m trying to fix a flat?) With a tube its 2 minutes. All manufactures seem to be going that way though.

    Almost pushing the button on Enve 45, but Zipp 303s almost identical at nearly half the price! Then you tease me, with some recommendations coming soon????

    Just a thought I have considered is “Rolling Resistance” says the Tubolite S, is almost as fast as Latex, and faster than tubeless, it weighs 23g.

    So a tubeless tyre on a hookless rim, without the tubeless valve (10g) and without sealant (30g). It would be lighter, no trouble inflating, punctures easily fixed without mess and no 3 monthly sealant change. The rolling resistance should be comparable. Downside, pinch flats? expensive tubes.

    • Nick, Bottom line, if you are uncomfortable going with tubeless and sealant, stick with tubed tires and the rims that work with them. The rest are differences in understanding or differences so small they aren’t worth losing sleep about.

      But since you asked, here’s my take on a few things. The whole process of changing a tube on the road takes more like 5 minutes but good mates will wait for you whether it’s 2 mins or 5 mins either way. It does take more time to set up your tubeless tire with sealant initially than a tire with tubes. Once set up, however, you don’t need to change anything and likely not even have to get off your bike if you get the kind of puncture in the treaded area on a tubeless tire with sealant that would require you to replace the tube in a tubeless or non-tubeless tire. If you get a tear in the sidewall of a tire that has sealant or tubes, you are going to have to put a tube in either way. But, if you are regularly getting more pinch flats using a tube in a tubeless tire than you would with no tube in a tubeless tire or a tube in a standard tube-type tire, how many mates will still want to ride with you every week, whenever we can resume doing that again?

      Not sure about your ENVE 45 price reference. Names can be maddening but the ENVE Foundation 45 is US$1600 and the Zipp 303 S is US$1300 so a US$300 price difference. The ENVE SES 4.5 AR with an alloy hub is US$2550, so yes 2X the price. I recognize price differences may be greater where you live. But, spoiler alert for my Zipp 303 S review, if it’s the SES 4.5 AR you are comparing, the two wheelsets are far from identical either in terms of specs or performance.

      As to rolling resistance and weight, it’s debatable whether there’d be a difference that matters to all but the time trialists among us. Or, to quote Aerocoach’s tests of inner tubes from butyl to latex and including Tubos: “At 45kph, the difference between the fastest and slowest inner tubes would equate to around 12sec over 16km/10 miles.” The Tubo is about halfway along that spectrum.

      Again, I think it best to do what makes you feel most confident about your choice. Steve

  • Hi Steve, new to ITK cycling, great site and really been enjoying reading.

    I’m picking up a set of 303s next week (thurs or fri), and going tubeless for first time. They will replace my HED Ardennes plus GP which were stock on my bike.

    I’m a solo roadie, 78kg, FTP 220 – maybe slightly higher. I’m mainly aiming to improve average speeds from 19/20 mph, hopefully closer to 21 mph, and also set some new pb’s on regularly ridden Strava segments. It is pretty flat where I live, a few short climbs at most. Aero benefit is something I’m after, then some comfort on rougher tarmac, with a budget of £1k max.

    Having seen other positive reviews I put my order in with a zipp supplying lbs. I am now a bit concerned now that some of these reviews are potentially paid for promotions.

    I am eagerly awaiting your review – any idea when it will be ready? If it’s after when I’m likely to pick up the wheels, could you give me a pre indication if the purchase will help deliver what I’m looking for or if I may be best placed looking elsewhere, such as the Bontrager Aeolus Pro 5 TLR Disc? Or even the Zipp 302 disc that the 303s replace?

    Appreciate you may not be in a position to answer this yet if still testing the wheels, no harm in asking though!

    Cheers, Martin.

    • Martin, GCN, Peloton, and others do paid promotions. Other sites that are ad-supported are often very friendly to products introduced by their advertisers. You can usually tell by seeing if there is any criticism about products being described or if they repeat a lot of supplier claims and talking points that read like they came out of a press release. I haven’t looked for a few days but hadn’t seen a review yet from someone that had ridden the 303 S more than once or twice.

      From what you’ve described about your goals and yourself, the 303 S won’t provide you the combination of things you are looking for. I’d suggest more or better training to get you w/kg up and a deeper, more aero wheelset if you ride mostly on flat roads. Steve

  • Please make a comparative review of the Enve foundation 45 VS Envr SES 45 VS Enve SES AR 45 ??

    • Aron, For starters, ENVE Foundation 45 is a road disc wheelset that you can only use with tubeless tires, ENVE SES 4.5 is a road rim brake wheelset that you can only use with tube-type tires, and ENVE SES 4.5 AR Disc (reviewed here) is a road and gravel disc wheelset that you can only use with tubeless tires. I’ve rated the SES 4.5 and SES 4.5 AR Disc as Best Performers. I hope to review the new Foundation 45 later this summer. Does that help? Steve

  • Kristian Kimberlin

    I was wondering if you had a review or knew of one on the Black Inc eighty as i live in a relatively flat area and have one lightly used for a steal locally and was wondering if it’s a good wheel or if i should save up a tiny bit and go for the ENVE Foundation 65’s? I am planning to go tubeless with either.

    • Kristian, haven’t reviewed that one. Being that deep (and heavy and narrow) it’s really an event wheelset rather than something you’d want to ride around on every day even on flat terrain. You can always use the search bar at the top of the page to see if I’ve reviewed something you are interested in. Steve

  • I recently purchased a set of 2021 303 Firecrest wheels. They are still in the box because I don’t has a suitable set of tires for them. Initially I ordered the Zipp Tangente Speed 28mm. Despite being told they are superior tires, they seemed too thin for the places I ride. Then I ordered a set GP5000’s only to discover they won’t mount and are not recommended. Finally I saw a YouTube video where the host mounted a set of Schwalbe Pro One TLE with Addix on a 303s. So I ordered those tires. Hopefully I’ll get my new wheels up and running this week. Zipp could do us a huge favor and make list of compatible tires like ENVE.

    • GPPassion, I’d just follow the ENVE compatibility list for wheels with hookless rims. BTW, the Schwalbe Pro One TLE are lighter than the Zipp Tangente RT28s. Steve

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