The Rapha Guide to Merino Wool Cycling Jerseys and Clothing

To understand why merino wool is an ideal material for cycling, put it under a microscope. Lower-grade wool is more coarse and resists moving with the body, causing irritation and itching, especially when moving. Rapha sources premium, ethically processed merino wool with an ultra-fine micron count.

In our Classic and Brevet jersey lines, we use an exceptionally fine 17.5-micron wool fibre, while our merino base layers, socks and warmers utilise an 18.5-micron diameter. Both specifications fall strictly within the globally recognised classification of superfine wool (15 to 19 microns). Because these fibres are so thin, they completely eliminate irritation while delivering next-to-skin softness.

While pure, 100% merino wool provides elite thermal regulation and next-to-skin comfort, it has mechanical limitations when adapted into technical merino cycling

clothing. Pure wool fibres have lower tensile strength and elasticity than advanced synthetics. Under the vertical stresses of cycling, a jersey made from 100% pure wool will inevitably sag, stretch and pull away from the body when the rear pockets are loaded with your spares and nutrition.

Rapha Performance Merino (RPM 150), a proprietary fabric that knits premium wool with recycled polyester, combats this. This fabric offers riders the courage to face long, challenging days in the saddle across a wide range of conditions, without sacrificing an engaged fit.

Found in our Classic and Brevet jerseys, this highly durable knit is constructed so that the yarn composition is strategically split across two faces.

Skin-Side Engineering: The merino wool is knitted predominantly on the interior face of the fabric. This ensures that only the soft, hypoallergenic, 17.5-micron fibres come into contact with the rider's skin, maximising thermal regulation and comfort.

Air-Side Engineering: The recycled cationic polyester is knitted on the exterior face. This synthetic shield drastically increases the fabric's tensile strength, ensuring pocket stability, structural shape retention and highly accelerated drying times as moisture is drawn from the core to the surface.

Warmers and Base Layers: For our additional merino cycling clothing, specifically our base layers and arm, knee and leg warmers, we utilise an 18.5-micron superfine BetaSpun wool.

Instead of twisting wool and synthetic fibres together conventionally, the BetaSpun process involves wrapping high-strength synthetic filaments around a central core of pure merino wool. This advanced construction vastly improves the garment's resistance to abrasions, reinforces its overall strength and significantly reduces pilling under the repetitive friction of bib short straps and outer layers.