Colnago

K.Zero TT Frameset-2015

Over the past few decades, the cycling industry has seen a radical movement toward specialization that placed a premium on aerodynamics. Ernesto Colnago was one of the few leading industry voices who insisted that wind-cheating properties shouldn't trump ride quality, so the engineers at Colnago were obliged to design K-Zero TT Frameset as a model that excels in both categories simultaneously. The result enjoys a claimed 7.54% improvement in aerodynamics compared to Colnago's previous Flight model, but it achieves those gains without putting the rider at risk on every turn and descent.

As with any frame, the K-Zero is only as good as the raw materials from which it's born, and Colnago's exclusive use of Toray's Japanese carbon means the K-Zero begins with an advantage over most aerodynamic frames on the market. Most Toray carbon is sourced from China or elsewhere, but the Japanese carbon used in the K-Zero is the most consistent in the world, guaranteed perfect every time, which is why it's the same stuff that Boeing insists on for its aircraft. This carbon is so sought after that Toray enjoys a degree of selectivity in who it sells it to, so Colnago is the only cycling manufacturer able to use it for 100% of its frames.

The bike's primary identity is still in its name, though, so Colnago knew the K-Zero TT would be judged first by its one-cyclist-against-the-wind properties. Toward this end, Colnago began with a catalog of NACA-derived tube profiles in order to establish an aerodynamically efficient base. These shapes were then shaped to address the drag coefficients affecting each disparate element of the frame in real-world conditions, not just the idealized time trial courses of marketing materials. Even the frame's wind tunnel testing was always done with a rider on board and pedaling. No fantasy drag conditions were used in the making of this frame.

The insistence on real-world conditions also means that the K-Zero handles like a Colnago. Like other aerodynamic frames, it cheats the wind while grinding along on the flats. Unlike those other frames, it doesn't sacrifice handling while climbing, descending, and cornering to do so. The road itself ?in all its infinite variations?is part of the data set that informs the K-Zero's design. It's meant to go fast, sure, but it's also meant to be fun to ride.

Since both the rider and the mutable environment were factored into the K-Zero's systematic development, you might assume that the frame's ancillary components were designed to contribute their small part to the overall aerodynamic system. You'd be right. For example, the brake calipers are tucked discreetly behind the fork and bottom bracket so as to avoid even that limited amount of drag.

Not even the stem and handlebars were left to chance, as Colnago is aware that the shape of the bars can drastically alter the entire bike's aerodynamic footprint. The K-Zero includes its own aerobars, which were designed to feed airflow along the head and top tubes' contours rather than into them. The bars also feed the brake and shift cables straight into the frame. The apparent excess of these details is indicative of the systematic approach to maximizing aerodynamics by small, mutually complementary gains spread throughout the K-Zero's construction.

There are some nods to customizability on the K-Zero, most notably the handlebar's fore/aft adjustability. The 77-degree seatpost, the frame's other key contact point, also allows for adjustment, letting you set the saddle back up to 30 millimeters to achieve your ideal hip tilt angle. After all, all the aerodynamics in the world won't help a rider contorted into a painful knot in order to fit on their bike.