THE NEW ZIPP 303 S ANNOUNCEMENT IS SURE TO RAISE A FEW EYEBROWS

Words - James Raison
Images - supplied by Zipp

In keeping with our “big or interesting stuff only” approach to media releases, we present the brand spankin’ new Zipp 303 S! The icon, the legend, the hero of all-round performance wheelsets has been given a refresh and it’s the first in a series of 2020 releases from Zipp. Their own words are: “The Zipp 303 S Series is just the beginning. Watch for more advanced speed coming from Zipp on May 28.” So stay tuned for more.

They’ve lost weight, had a face-lift, seen a price drop, and gotten into gravel so there’s plenty going on.

The rear 303 S showing off its stealthy new graphics

SPECS

Let’s dive into the nitty gritty of numbers first:

Price: $1,300 USD | € 1,100 | £ 985
Tire compatibility: Clincher Tubeless Ready (more on this below)
Weight 1,540g
Internal Rim width 23mm
External Rim width 27 mm
Optimised for 28 mm tyres
Centre lock disc
Hubs: Zipp 76/176 Disc Brake hubs,
Symmetrical Rim profile
Rim finish UD fiber / Bake-On labels / Matte clear coat
Nipple material Brass
Spoke type CX-Sprint
Spoke count 24 Spoke pattern 2 Cross
Driver compatibility SRAM XDR, SRAM/Shimano Road
Thru axle 12x100, TA 12x142
Steel Cartridge Bearings
3 Pawls Leaf Spring Driver Mechanism

HOLISTICALLY FAST

We got a very comprehensive info kit from Zipp about the wheels and it focuses on more aspects of riding than I’d expect from a wheel release.

They’re claiming a healthy performance gain with their new family of wheels with 10 watts of efficiency savings over the previous generation; “The combination of a large tubeless tire, low tire pressure, a wide rim profile with optimized tire interface, and rim laminate create a more efficient ride; to be faster on or off the pavement.”

Zipp has focused on:

Reduced wind resistance through smoother rim/tyre interface. The hookless rim doesn’t pinch tyres inwards like a hooked one does so the new profile makes the tyre less lightbulb shaped. Zipp claims “a 10 watt savings vs. a top peer wheel in total power required to ride 40kph on a flat road with a 28mm tire, according to internal Zipp testing”.
Lightness. The 303 S shaves a whopping 155 grams from its precursor 302 MY20.
Reduced rolling resistance. Zipp’s new wheels are claimed to decrease contact patch deflection by allowing very low tyre pressures. Tyre sag is reduced and rolling efficiency is increased.

MIXED TERRAIN MONSTER

Welcome to 2020 where every bike is a gravel bike and every component had better be built to withstand the punishment of unsealed roads. You can be cynical if you want but there’s not many detriments to making sure bike equipment can handle more punishment than it could several years ago.

Zipp has used a customised, hellish-looking, RollingRoad contraption where some poor bugger had to ride along constant and major bumps to see how many watts and tooth fillings came out of him. The short summary; the new wheels helped him put more power out, and retain more teeth, than Zipp’s previous versions.

There appears to be significant improvements in absorbing impacts. The tyre with low pressure, more compliant rim and spokes, are able to conform to the bumps rather than shooting the bike and rider upwards. Now, when our test set arrives they’re going onto a gravel bike and we will treat them very poorly. Because it’s fun and it makes for more interesting reviews!

TYRE SPECS

Zipp has a fairly detailed list of tyre compatibility requirements for the new 303 S, but haven’t made a specific list of approved tyres. That’s unsurprising given how long the list would be for a gravel/road rim. I sure hope it’d be long anyway!

So, the first thing is 25 mm or bigger. All you gnarled old grumps insisting on still using 23 mm rubber aren’t invited to the 303 S party. Things get properly interesting with tyre pressures.

MAXIMUM PSI OF WHAT?!

Hold onto your butts because Zipp recommend a maximum PSI of 72.5 for the 303 S. That. Is. Bonkers. Now, I’m an absolute zealot for low tyre pressures so this doesn’t bother me at all but it’ll come as a shock to many.

Zipp’s parent company SRAM has their new AXS Tyre Pressure Guide that’ll help you find the ideal pressure for most rims and they’re encouraging some quite low pressures.

Zipp, for the 303 S, has given recommended tyre pressure values by weight for 28 and 30 mm tyres:

45 kg - 49F/52R, 45F/47R
50 kg - 50F/53R, 46F/48R
55 kg - 51R/54F 47R/50F
60 kg - 52F/56R, 48F/51R
65 kg - 53F/57R, 49F/52R
70 kg - 55F/58R, 50F/53R
75 kg - 56F/60R, 51F/55R
80 kg - 57F/61R, 52F/56R
85 kg - 58F/62R 53F/57R
90 kg - 59F/64R, 54F/58R
95 kg - 60F/65R, 55F/60R
100 kg - 61F/66R, 56F/61R
105 kg - 62F/68R, 57F/62R
110 kg - 63F/69R, 58F/63R
115 kg - 64F/70R, 59F/65R

There’s no stipulated minimum tyre pressure with Zipp instead saying “we recommend our customers to experiment before fully committing to a low tire pressure.”

TUBELESS ONLY

Tyres don’t have to be set up tubeless with sealant and all, but Zipp are insistent that a tubeless beaded tyre is essential. ENVE made the same stipulation with their 3.4 and 4.5 All Road disc wheels. The 303 S’s hookless rim profile “will not securely retain the tire in place” of a standard clincher. That will be an ongoing concern for owners who don’t want a full tubeless setup. My experience is tubeless tyres tend to be a little heavier, a little more expensive, and a little less comfortable when used with a tube compared to full tubeless setup, or a standard clincher. Plus it’ll discount some of the lovely thin-walled clinchers from being used like the legendary Specialized Turbo Cottons.

WARRANTY

2019 saw warranties become a bona fide battleground for high-end wheel brands. Zipp is extending that to the 303 S with the original owner only getting “warranty coverage against manufacture defect, and impact damage warranty coverage during intended use that will cover all 2021 Zipp products and beyond.” The wheels must have been purchased through authorised Zipp retail channels, and require proof of purchase.

It’s good to see warranties become so comprehensive. These are big ticket items after all. Beware buying second hand though because you ain’t getting that premium treatment transferred from the original buyer.

WRAPPING UP

The wheel market has become fascinating in the age of disc brakes. Carbon rims have dropped to ever-cheaper pricepoints, carbon braking isn’t a development concern any more, widths have rapidly grown, and the gravel market boom has seen more of a focus on multi-use sets.

It’s heartening to see more focus on all-round wheels rather than a focus on just lightness and just aerodynamics. The Zipp 303 S sees a product adding comfort, resllience, lightness, and aerodynamics over the previous generation then dropping the price and backing it with a thorough warranty.

Hopefully we’ll be getting a test set and we can tell you whether Zipp has delivered on its many promises!