Zipp 303S review

Long having been at the forefront of aerodynamic innovation and development, Zipp is a name typically associated with ‘aspirational’ high-end builds.

The 303S, however – despite still sitting on the wrong side of the £1,000 barrier – represents quite the departure for Zipp, bordering on being an achievable upgrade.

Aimed squarely at those who wish to go fast, the 303S is for road racers and those who like to go head to head with the clock, but the 22.7mm internal width and recommended lower tyre pressures heavily suggest a gravel bike or cyclocross intention as well.

Zipp 303S wheels details and specifications

As well as being wide, the 303S is a sensible weight at 1,558g. Measuring 45.3mm deep front and rear, and with a maximum external width of 27.3mm, the profile tapers. It still offers a blunt spoke bed but without maintaining width in the way some other wheels do.

24 bladed Sapim spokes per wheel are laced in a two-cross pattern. Serviceability is good, the spokes are J-bend and the nipples are external.

The hubs are similarly serviceable, the end caps being removable by hand and no tools necessary to clean and re-grease the drive system.

Three leaf-sprung pawls hook into 36 teeth in the driven ring, making for a solid 10 degrees of engagement. Shimano and SRAM cassette compatibility is available.

Zipp states these wheels are for tubeless tyres only, because the rim walls are hookless.

This isn’t the issue it may have been a few years ago, because most tyres are now tubeless-ready, and have a stronger bead to prevent being blown off the rim.

Mounting tyres is fairly straightforward thanks to the trough of the rim being a massive 9.9mm deep.

The bead seat diameter – where the tyre ideally locates when inflated – is a European Tyre and Rim Technical Organisation (ETRTO) pleasing 622.2mm, meaning most tyres should seat with a satisfying audible confirmation.

Zipp 303S wheels performance

The 303S are what Zipp would like us to expect; snappy and direct. Sprinting and climbing out of the saddle feels intuitive and no power seems to be lost. Cornering is confident and predictable – unless the surface is bumpy.

Even then, the bike stays on line, but the lateral stiffness of the wheels does mean you get rattled around a little. That stiffness is felt when in a straight line too; it’s not an uncomfortable ride as such, but you’re never left wondering how rough the surface you’re riding on is.

There were several instances when it was my perception that speeds were higher for similar perceived effort levels.

Measured similarly at 0.1mm out of true and 0.2mm out of round before installation, both wheels had less than 2 per cent variance in spoke tension.

Given 250km of abuse on the worst roads I know in a variety of conditions, the front wheel seemed to suffer more than the rear.

There were no particular impacts that could have been individually responsible for this, but the front tension variance was 4.5 per cent when measured after testing, with trueness at +/- 0.4mm and roundness +/- 0.3mm.

By contrast, the rear was 0.2mm out of true and maintained both +/- 0.2mm roundness and 2 per cent spoke tension variance.

It's a nice bonus that the 303S wheels are supplied with a double wheel bag, including Velcro straps to secure the wheels and a small pocket for quick-release skewers. This worked equally well for carrying a couple of tools.

Also included are rotor lockrings, and the rims arrive pre-taped for tubeless installation.

Zipp 303S wheels bottom line

This is a zippy wheel that delivers snappy confidence-inspiring performance for those who like to go fast. It's easy to mount and maintain, while the weight is not excessive.

If you race, whether it be road racing, time trials, cyclocross or performance-related multi-surface touring, the Zipp 303S is a high-ticket option at a relatively achievable price.

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