CADEX Aero Cotton: a tyre engineered to win at the highest level

Leading-edge aerodynamics and a high-TPI cotton casing deliver the best of both worlds in CADEX's new flagship race tyre, which has already won the queen stages in the Tour de France and the Giro d'Italia

Photos: COR VOS and CADEX Words: Simon Smythe

This article was produced in association with CADEX

When CADEX launched the Aero Tubeless tyre in 2022 it was more than just fast – it was a literal reshaping of aerodynamic integration. In 2025, the Aero Cotton takes it a step further. Building on the proven aerodynamic advantage of its predecessor and introducing a faster-rolling 320 TPI cotton casing, the new tyre is the ultimate in speed and performance.

At its launch, CADEX’s global head of product, Jeff Schneider, said: “The Aero Cotton brings together the elements that matter most for pro riders – low rolling resistance, confident handling, and aero performance. With a refined hookless profile, high-TPI cotton casing, and our latest compound technology, it’s built for real-world race conditions.”

He was proven right very quickly. The CADEX Aero Cotton won at the highest level after Jayco Alula's Ben O’Connor rode it to victory in the Tour de France's queen stage on the hors catégorie Col de la Loze – the highest point of the race. Earlier, in May, Chris Harper used the Aero Cotton for a spectacular solo victory in the epic Giro d’Italia stage to Sestriere, which included the unmade Colle delle Finestre – the highest point in the Italian Grand Tour. The Jayco Alula and Liv Alula Jayco teams have been riding the tyre in all races over all parcours beginning with the Tour of Flanders in April, where brutal pavé, changeable weather and high-speed racing require a fine balance of speed and reliability.

A new benchmark

The original CADEX Aero Tubeless set a new benchmark in tyre design by demonstrating that aerodynamics is about more than just a tread pattern. Using computational fluid dynamics (CFD) and wind tunnel testing, the brand reimagined how a tyre could control airflow across a wheel system. Its engineers conceived an oval‑shaped profile with taller sidewalls and a thicker midsection that reduced drag not only with CADEX’s own rims but with competitors’ rims too.

Tested against competitor wheels paired with common commercially available tyres, the combination of the CADEX Aero Tubeless tyre and CADEX Ultra 50 wheel came out on top, with as much as 5.5 watts of difference in power required. And in the second test, all wheels that were mounted with the CADEX Aero Tubeless tyre displayed better aerodynamics, improving power savings by as much as 5.22 watts.

In 2025, CADEX has raised the bar again. The CADEX Aero Cotton has the same aerodynamic shaping that made the original Aero Tubeless revolutionary, but now there’s a new high-TPI cotton casing and an advanced compound, enabling it to deliver top-tier performance in an areas.

The hallmark of the original Aero Tubeless was its aerodynamic profile. That principle carries forward in the Aero Cotton. It retains the taller sidewall and oval-shaped casing that creates a smooth shape with CADEX and other hookless rims for optimal aero performance. As with the original design, improving the tyre-rim interface is proven to reduce drag and enhance airflow where traditional designs can suffer significant performance losses.

At its core, the Aero Cotton features a new 320 TPI Cotton Race Casing. Cotton is a material long prized for its high thread density and exceptional suppleness. It supplies responsive, instant handling while keeping weight to a minimum.

Meanwhile, a completely reengineered RR-S2 silica compound cuts rolling resistance by a huge 30% compared to previous compounds. The tread design follows a proven formula with refinements: a smooth centre strip minimises rolling resistance, while micro-textured shoulders increase mechanical grip and water dispersion for confident control in all conditions.

The Aero Cotton uses CADEX's Race Shield puncture protection, a lightweight Kevlar centre patch that resists cuts from road debris without adding unnecessary grams, while a hybrid Carbon-Zylon bead with superior elongation resistance provides a secure, airtight fit on hookless rims.

The CADEX Aero Cotton represents a union of leading-edge innovation with traditional materials, validated by the wind tunnel, real-world pro racing and by unforgettable stage wins in the Tour de France and Giro d'Italia. This is the ultimate racing tyre.