Why make an aero climbing bike? Firstly, because the climbs are only part of anyone’s ride and on the rest of any route it’s as important as ever to be aero. Secondly, because the pros climb so fast that aero remains a significant consideration even at typical gradients of 8%. Of course, everyone wants both lightness and low drag, but with aero shapes being heavier, the challenge for a climbing-focused bike is to save the most watts while adding the fewest grams. Our team nailed it.

How aero is it? In the wind tunnel, at effective wind angles of 0-5 degrees (ie a calm day, or headwind to moderate crosswind) the new O2 VAM is only 5W behind the OSTRO VAM, which itself is the fastest aero bike on the market. Across a full sweep of angles, it slashes the gap by 50% versus the previous version. For such a light bike, that’s outrageous. On the road, it means that your climbing bike will be faster than many brands’ much heavier dedicated aero offerings.

STIFFNESS, HANDLING. CHECK. CHECK.

The new O2 VAM is as stiff as the mighty OSTRO VAM and feels inspirational when you stamp on the pedals. You’ll be attacking just to feel it. The handling geometry is shared, too, which means incredible poise at high speed on descents, confidence at big lean angles, and the agility to outmanoeuvre a house fly. After all, a bike for the mountains has to be great on the way down, too.

The most visually apparent features of the O2 VAM relate to ride comfort as well as weight saving. The external seatpost, ultra-thin toptube and dropped seatstays all work together to promote controlled deflection at the saddle. The latest UCI rules allow a minimum tube thickness of 10mm and that is exploited in the toptube ahead of the seat cluster. This section bows in a controlled way under the reverse force of the rider on the saddle when the bike hits a bump. In combination with the external seatpost, which eliminates the mass and overlap of a conventional seatpost, this enables a small amount of ‘travel’ at the saddle over rough roads.

ENGINEERED OBSESSIVELY

To craft a bike that is everything you've ever wanted took everything we've ever learned, and more. In pursuit of the ultimate climbing bike, our relentless R&D broke new ground, pushed boundaries and polished every detail.

The new 28//33 wheelset was designed to complement the new O2 VAM and represents an equally remarkable breakthrough in lightness and aerodynamics. The 28//33 weighs a feathery 1,146g as tubeless clinchers optimized for 28mm tires. They feature differentiated front and rear depths of 28 and 33mm, measure 23mm internally and 28mm externally, and use exceptionally light and strong carbon fiber spokes. As well as a substantial weight saving, they also reduce drag by 10g from the previous THIRTY wheelset and greatly boost stiffness, and therefore responsiveness and acceleration.