Vitus ZX-1 EVO CRS Ultegra Di2 review

The ZX-1 is Vitus’s latest flagship aero race bike, designed in conjunction with the Silverstone-based aero specialists, Total Sim.

The aero road bike of Northern Ireland’s Vitus has seen a total refresh for 2021, with a new, aerodynamic frameset designed from the ground up to be as fast as possible.

Despite boasting the cheapest price tag of the aero bikes I tested, the 8.07kg ZX-1’s deep-section wheels, electronic gears and aero-profiled carbon components wouldn’t look out of place on a much pricier bike.

Vitus ZX-1 EVO CRS Ultegra Di2 aero claims

Vitus says the new ZX-1 cuts aerodynamic drag compared to its predecessor by 18 per cent in a headwind, and up to 45 per cent in strong crosswinds. And the stout kammtail aerofoil tubes, hidden cables and deep-section carbon wheels certainly look the part.

Unlike many brands, Vitus doesn’t claim the bike is ‘X seconds faster than every other bike over 40km’. Partly because the new ZX-1 has only been benchmarked in the wind tunnel against its predecessor and its Vitus Vitesse sibling.

Vitus also points out that performance differences between aero road bike framesets are relatively small, and pale into insignificance once a rider is involved. What matters is whether you can get into an aerodynamic position and stay there.

That’s true, but it strikes me as an odd choice for Vitus to spec a non-adjustable, integrated handlebar. The Vision Metron 5D is a slippery, full-carbon monster that feels fabulous when yanking on the drops in a sprint. If it’s not the right fit for you it might be a pain, though, because there’s no way to change the handlebar width or stem length.

Stack height changes are also limited by the integrated top cap to about 5mm in either direction, unless you’re willing to cut the steerer tube. Fortunately, the bar isn’t proprietary, so you can swap it for a non-integrated option.

Vitus ZX-1 EVO CRS Ultegra Di2 geometry

In terms of fit, the longish reach and low stack figures (396mm and 562mm on my size Large) mean the riding position is racy.

The head- and seat-tube angles fall just on the less aggressive side of race-bike geometry, sitting at 72.9 and 73.3 degrees, respectively. It’s a small difference but combined with the 1,000.4mm wheelbase and 410mm chainstays, it adds a touch of stability to the bike's handling without muting the bike's responsiveness.

Vitus ZX-1 EVO CRS Ultegra Di2 kit

Setup as stock (without pedals or bottle cages), the ZX-1's 8.07 kg weight won’t wow weight weenies but it’s competitive within its category. The reality is that weight isn’t a meaningful performance metric for aero bikes. Provided they’re in the same ballpark, a few hundred grams doesn’t make much difference to how fast you’ll be able to ride on anything but the steepest and longest climbs.

The chunky, sculpted frame tubes make it feel like none of your input is being wasted, and the stiff front end makes for a bike that’s precise and confident in the corners. It’s a rapid descender too, especially on good roads where you can take sweeping lines.

Credit for some of this is due to Shimano’s hydraulic disc brakes, which provide heaps of power and control in all conditions so you can push the bike’s limits more easily.

Like the brakes, the ZX-1’s Shimano Ultegra R8070 Di2 drivetrain is flawless, with accurate and reliable shifting no matter how you abuse it. Vitus has swapped in a KMC chain and Sunrace cassette, but you won’t notice these subs while riding.

The Reynolds AR 58/62 tubeless-ready carbon wheels are the star of the build, though. They handle excellently for deep wheels, even on gusty days, and the difference they make to your speed on flat and rolling roads is tangible.

The tyres are the only place the spec feels compromised. The 25mm Schwalbe One TLE tyres measure just over 27mm wide when inflated to 60psi and make for dependable training rubber, but there are faster, more supple options. They’d also help with comfort because you do feel road imperfections at both ends.

The slim, dropped seatstays do a good job of managing big bumps at the rear, but it’s a focused ride overall. There is clearance for tyres up to 30mm if you want to ride on rough stuff, though.

Vitus ZX-1 EVO CRS Ultegra Di2 bottom line

The Vitus ZX-1 is a bargain. Aero road bikes often have you considering whether you really need two kidneys, but that’s not the case here.

If the integrated handlebar fits you, there’s little about the build that needs upgrading, and the frameset and components combine to make a fast and purposeful race bike.

While the glossy grey paint job might not excite much on paper, it’s a great-looking bike in the flesh, and – more importantly – a joy to ride.