There is no such thing as too much wind for aero wheels," says Olivier Mouzin, "wind is good!" To prove this, the development manager at French wheel manufacturer Mavic sets up a Comete disc wheel in the wind tunnel, which we want to test as a reference. He closes the door to the measuring chamber and starts the generator that supplies the wind tunnel at the Technical University of Lyon with high voltage electricity. The fan gets up to speed. Through a window, we observe how the impeller in the holding device is accelerated by a treadmill and placed in the airflow at an increasingly shallow angle.
On the monitor of the control stand, we follow the forces that the airflow exerts on the wheel. When the wind blows on the wheel from an angle (22 degrees), we see proof of Mouzin's theory: the curve that shows the force required to turn the wheel drops rapidly. The disc wheel rotates almost without force, "sailing" on the wind. The thrust from the airflow and the resistance are in balance. In a race, this means that with a corresponding crosswind and high speed, a cyclist hardly has to expend any energy to keep this disc wheel in motion.
Sounds good - but unfortunately crosswinds not only push the disc wheel, they also interfere because they affect the steering via the large contact surface. Disc wheels are therefore usually only used on the rear wheel and not at all in stronger winds. In this test, we are therefore focussing on aerodynamic spoked wheels at prices ranging from 700 to an incredible 3,690 euros. They all aim to maximise aerodynamics with high rim profiles and few spokes - the material for competitors.
SHORT & SHORT
Aero wheels are detailed work. Few, flat steel spokes combined with streamlined high-profile rims reduce air resistance. The manufacturers implement this recipe in different ways. Ambrosio lags behind because of its many round spokes. Citec offers the best compromise between aerodynamics and suitability for everyday use. Lightweight builds a spoked wheel entirely from composite material: the lightest wheel in the test is by far the most expensive.
You can find these wheels in the test:
Ambrosio X-Carbo, Bontrager Race X Lite Carbon Aero, Campagnolo Bora G3, Citec 2000S aero, CKT Splendor, Corima Aero, Easton Tempest II Carbon, Gipiemme Carbon 5-5, Lightweight Obermayer, Mavic Cosmic Carbone SL, Ritchey WCS Carbon, Tune Olympic Gold, Xentis Mark 1, Zipp 808
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