This Road Race Bike Has No Seat Tube: Colnago Y1Rs

Cycling’s WorldTour is the pinnacle of road racing globally. Sponsors spend incredible amounts of money chasing results. Slim margins win road races, and air resistance is the largest obstacle to speed. Colnago launched an all-out attack on aerodynamics to produce the Y1Rs.

Announced today, the Colnogo Y1Rs is a wild departure from traditional bicycle design. This road bike removes the seat tube, which is present on almost all other road bicycles. By doing this, the premium race machine aims to reduce air drag, one of the biggest forces slowing cyclists on the move. It hits the market today and will cost an astounding $6,750 for the frameset alone.

The side profile of the Y1Rs reveals the obvious empty space vacated by the seat tube, which normally runs from the rearward termination of the top tube down to the bottom bracket. Colnago eliminated this, creating a “Y” shaped juncture of a very short seat mast with the seat stay(s). The “seat tube,” if you can call it that, hugs the rear tire from the bottom bracket to join the middle of the seat stay, where it splits into two.

This stunning departure from almost all other road frames isn’t the only thing Colnago did in the search for speed. From the front of the bike, a similar “Y” shape disrupts the handlebar’s top. Again, visually stunning, the extreme departure from traditional drop bar design lessens aerodynamic drag. But Colnago also claims it’s stiffer and, thus, more efficient during sprints.

For decades, Colnago bikes have been regarded as stunning in form. The skeptic in me wanted proof that these striking shapes were more than “wow factor” marketing attempts. The brand delivered with a barrage of white papers and data. Read on for my distillation of the important bits.

Computational Fluid Dynamics: The Buzzword for Aero Everything

Computational Fluid Dynamics (CFD) is touted as the holy grail of designing anything that slips through the air or water with the least amount of drag. From Formula 1 race cars to America’s Cup sailboats, the CFD acronym is heavily used to portray the epitome of aero engineering.

What CFD Does

CFD is incredibly powerful, and engineers use software to analyze fluid flows numerically. But all the impressive computer graphics representing airflow around frame tube shapes and accompanying reams of data are just that: theoretical behavior that lives in a computer and not the real world.

Some bicycle brands stop there. Colnago’s CFD analysis, done in partnership with Khalifa University in Abu Dhabi, UAE, and Politecnico in Milano, Italy, was verified by quickly prototyping 3D-printed models and wind tunnel testing. Colnago drilled 70 holes into prototype frames in the areas most impactful to airflow and mounted pressure sensors. It then ran each prototype through a battery of wind tunnel testing.

Wind Tunnel Validation

The wind tunnel data was then fed back through CFD analysis to produce a refined, real-world analysis. And the cycle was repeated.

Colnago didn’t just test the bicycle. It also produced 3D-printed adjustable mannequins to “ride” the Y1Rs prototypes in the wind tunnel. These human forms replicated the size and position of typical WorldTour competitors. The rider is the most significant contributor to drag, which also affects the behavior of the air around the frame tubes and wheels.

Engineers tested the bike and bike+rider combination in a range of yaw angles to the wind. Conlago used ranges from 0 degrees to 12.5 degrees to the wind, claiming research has found that these are the most common in bicycle riding. It also used a wind speed typical for racing, 31 mph, with two bottles aboard the frame.

Colnago didn’t stop at the unique “Y”-shaped frame, handlebars, and frame tube profiles. It also analyzed the effects of the standard, round water bottle. Other brands have gained aero efficiency with proprietary aero-optimized bottles and bottle cages, but Colnago stuck with the standard bottle because it’s the lightest and unavoidable in racing.

So, What Does This All Mean?

The short and sweet of the incredibly massive amount of data collected and analyzed can be distilled to the following.

Colnago claims the combination of the Y1Rs frame and the matching handlebar/stem combination (dubbed the CC.Y1) results in a 19% reduction in frontal area compared with its current “normal” road race bike, the V4RS. The V4RS has won the Tour de France three times under Tadej Pogačar. And last year, it rocketed the Slovenian phenom to an incredible triple of the Tour d’Italia, Tour de France, and the World Professional Championship.

The CC.Y1 handlebar alone produced a claimed 16% gain in aerodynamic performance.

Colnago claims the Y1Rs only saves 3 W over the best competitor at 0 degrees wind yaw. But it claims a massive 19W advantage for an average drag, weighted for yaw angles that are most common in racing. And 19 W throughout a 3-week road stage race covering thousands of miles is more than just “marginal gains.” Equally impressive is the 20W+ gain for both yaw angles compared to the Colnago V4Rs.

OK, What Else?

Although improved aerodynamics was the primary vision for the Y1Rs, Colnago claims other significant advantages of its unique shapes and design.

It doesn’t take a genius to understand that the lack of a continuous seat tube means more vertical compliance at the saddle. The Y1Rs’ seat post also has a more laid-back angle to improve compliance.

Racers don’t care about the comfort of enhanced vertical compliance if it means reduced power transfer. But Colnago claims advantages here as well. Compared to its V4Rs, the brand states that the Y1Rs is 3.5% stiffer out of the vertical plane in the standing sprint position and are just as stiff in the seated position.

For the sprinters, Colnago claims the CC.Y1 handlebar/stem combination is 16% stiffer laterally and vertically than competitors. This theoretically squeezes out wattage for sprinting and climbing.

Finally, the weight. Light is right in racing, but the Y1Rs weigh 242 g more than the V1Rs for the frame, handlebars, and headset combination. However, racing professionals and studies assert that aerodynamic gains trump weight, even at slower, non-racing speeds.

Final Details on the New Colnago Y1Rs

The Y1Rs comes in five sizes and can accept up to 32mm-wide tires.

Three paint schemes are available: a black-and-white replica of UAE Team Emirate, a glittery white replica of women’s team ADQ, and a Pogačar World Champ Rainbow edition.

And, yes, pricing. Hold on to your wallets. $6,750 for the frameset! You can also pick between five premium builds, all with top-tier group sets from Shimano, SRAM, and Campagnolo. You’ll have to cough up between roughly $13,000 and $17,500. Do you hear that? It’s the sound of the wind sucking the cash out of your bank account.

But this is a racing-only bike for the pinnacle of professional bicycle racing globally. And, like Formula 1, saving money isn’t on the radar in the pursuit of speed.

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