Zipp 404 Firecrest Tubeless Disc wheelset review

Zipp’s 58mm-deep 404 Firecrest wheelset has been around since 2011 and helped set the gold standard for aerodynamic road wheels.

For more than a decade, the 404 remained the Indianapolis brand's most popular wheelset, with its sponsored riders and in terms of sales performance.

The shallower 303 Firecrest has recently overshadowed its deeper aero cousin, but the new 404, with its lower weight, claims of improved performance and significantly cheaper price, could be the wheel that puts the 404 Firecrest back on top for riders in search of a fast, mid-depth road wheelset.

Zipp 404 Firecrest Disc details and specifications

I was hugely impressed with the 303 when I tested it in May 2021 – so much so that I awarded it five stars in my Zipp 303 Firecrest review. With a 40mm-deep, 25mm-wide (internal) rim, it’s a wheel that excels at road, gravel riding and even cyclocross.

So why would you need the 404 wheels? Well, Zipp suggests these are the ones to go for if flat-out, fast road riding is your thing.

Updated rim shape

The key element of the new 404 tubeless, disc-only wheelset, launched in June 2021, is the rim shape. It’s a wider evolution of the old Firecrest’s broader, blunted edge, with the deep-section shape featuring Zipp’s signature dimples.

It also adopts the hookless and tubeless-specific rim design from the 303: the hookless rim is lighter and stronger than a traditional hooked rim, according to Zipp.

The brand hasn’t quantified how much of a weight saving comes from the hookless design, but the new 404 wheels are 350g lighter than the old set, so there’s a significant drop across the board.

The 404 Firecrest rim shape is 58mm deep, as expected for a 404, but now it’s broader, too. The new rim also features a 23mm internal rim width, growing significantly from the 17.25mm internal width of the old clincher wheelset.

The new shape is optimised for use with 25-28mm tyres. Zipp recommends 90kg riders should use 28mm, while those under 90kg should pick the 25mm tyres.

Although Zipp says the new rim shape is slightly less aero than the old model (which had a narrower frontal area), the latest model comes with big weight savings (350g) and redesigned hubs with improved bearings.

The rim also features an evolution of Zipp’s long-standing dimpled surface pattern.

Zipp claims the golf ball-like dimples create a thin boundary layer, keeping air attached to the rim surface, thus reducing drag.

This, along with the improved efficiency of the wheelset, means that Zipp claims the new 404 design is 4.4 watts faster than its predecessor.

Despite the aero penalty of a wider rim, Zipp claims a wheel and tyre combination that rolls more smoothly over imperfect road surfaces makes for a more efficient wheel on the whole.

Hookless design

Zipp says a hookless rim, which does away with the hooks found on traditional clincher wheels to retain the tyre, is cheaper, easier and greener to make, by using solid moulds rather than the one-use silicone moulds required by hooked designs.

Silicone moulds produce more waste, according to Zipp, both from the mould itself and due to the machine finishing required.

As well as producing less waste, Zipp says the simplified process also results in a cost-saving to the rider, and the new 404s are significantly cheaper than the old wheels (hundreds of pounds cheaper, which is a rare thing in today's market).

However, hookless rims have caused some riders (and brands) concern since their introduction, and not all wheel and tyre manufacturers have updated their designs to the revised ETRTO (European Tyre and Rim Technical Organisation) and ISO (International Organisation for Standardisation) standards for tubeless.

Hookless rims must be used with a compatible tyre, so while most tyre brands offer updated designs, check before you fit your tyre of choice. That said, many of the best tubeless road tyres are now approved for use with hookless rims.

As part of the testing process, I’ve run the 404s with tyres from Pirelli, Zipp, Schwalbe, Specialized and Michelin. All have been easy to fit, have sealed at the first time of asking and retained pressure. Anyone with past experience of tubeless road tyres will understand how impressive that is.

Weight and build spec

My test pair weighs in at 703g for the front wheel and 824g for the rear (a very respectable 1,527g for the pair), including tubeless tapes, lockrings and valves. Zipp claims 1,450g, but that's without the accessories required to get them on the road.

The rims are laced with 24 standard J-bend spokes both front and rear through the ZR1 hubset.

You don’t get the bells and whistles of the Cognition V2 hubset found on Zipp’s NSW range, but the six-pawl freehub, with 66-point engagement, results in a rapid pick-up angle of 5.45 degrees.

The hubs are designed around road thru-axles and come with 12mm end caps as standard. These are push-fit into the hub body, so I’d recommend a little grease and making sure they are fully pressed in to avoid any undue noises.

Zipp’s new warranty covers all wheels and components bearing the new Zipp logo and covers against impact damage under normal use.

Zipp 404 Firecrest Disc performance

Zipp’s parent company, SRAM, has an online tyre pressure calculator that it advises using when setting up the 404s (you can also use our guide to road bike tyre pressure, of course).

Input your wheel, tyre of choice, height and weight, and riding conditions and it’ll calculate what it deems to be the optimal front and rear pressures. This gave me numbers lower than I’d have guessed for a fast road tyre, but the results out on the road were great.

The new wheelset is much more comfortable than the old one, which I’ve run for a number of years on my own bike. The lower pressures don’t slow it down, they just give better comfort and grip.

With a wider rim, the new design produces a better fit and profile for the wider road tyres preferred by many riders today, while Zipp also says the wheel build transmits fewer road vibrations than the previous version.

The 58mm rim depth makes this a tangibly fast wheel on the flat and, unlike some deep-rimmed rivals, they’re controllable in blustery conditions.

Of course, any rim approaching 60mm deep is going to have a rather flat side that will catch in strong crosswinds. And indeed, the Firecrests do if it’s really blowing, but it’s not a violent, course-altering shove, more of a pressure that is controllable through a shift in weight.

The relatively low weight of the 404s means the deep-rim aero advantage isn’t a disadvantage when it comes to climbing.

In fact, the combination of low weight, superb build stiffness and the quick engagement of the freehub all make for a wheelset that responds in an instant to pedal input when out of the saddle hauling up a climb.

It also makes for a lightning-quick set of wheels when you want to sprint on the flat or accelerate up to speed on a descent. Light, stiff, responsive, it's everything a modern aerodynamic wheel should be.

Zipp 404 Firecrest versus 303 Firecrest

I’ve heaped plenty of praise on the Zipp 303 Firecrest wheelset, which has a 40mm rim depth, 25mm internal width and actual weight (on my test set, with tubeless tape, valves and rotor lock rings) of 1,409g.

They have a brilliant mix of low weight, ride feel, speed and, above all, versatility that overall made me describe them as my all-time favourite wheels for the road and beyond in my original review.

So would I now recommend the 404s instead? Well, the additional depth of the 404 Firecrest means it beats the 303 in terms of pure speed on flat or rolling terrain, particularly on the road.

If you’re running 25mm or 28mm tyres, the 23mm internal width of the 404 is ideally shaped, but if you’re going slightly wider and running 28mm rubber or beyond (with a set of all-road or gravel tyres, for example), the 303’s 25mm width will start to have the edge.

Depth and width aside, broadly speaking the wheels share the same rim tech – dimples included – and the same hubs and construction, too.

Ultimately, the choice between the two comes down to your own preferred riding style and where you love to ride. If it's all about flat-out speed on the road, be it competitive or not, the 404 Firecrest is your better choice.

If, however, you ride on more diverse terrain, both in terms of topography and road (or trail) surface, then the 303 Firecrest offers more versatility. It handles bigger tyre sizes, feels a little more compliant with those plush tyres, and, at 1,409g a pair, there’s a weight advantage while retaining a 40mm rim depth.

For me, it's the 303 Firecrest, but that's because of where and how I ride. But for a lot of road riders considering Zipp’s range, I can’t see them looking beyond the 404 Firecrest.

Zipp 404 Firecrest Disc bottom line

Overall, the 404 is a superb wheelset if you ride predominantly on the road or like to race, whether that’s against the clock or with your riding buddies.

At this moment in time, I can’t think of a better wheelset for road purists; especially not one at this price.