Drag force on rotating racing cycle wheels

Abstract The professional cyclist employs a variety of wheel designs in an attempt to reduce drag and improve overall performance. such wheels include the partially or fully clad wheel, the racing disc-wheel and the aero-rim. Little if any openly published data on the performance of these wheels is available. This paper describes a series of experiments carried out on a full size racing cycle wheel, fitted with different degrees of cladding, and rotated at various air speed/wheel speed ratios. The results are compared with similar tests performed on the racing disc-wheel and the aero-rim wheel. The results showed that for wind speeds less than or equal to 10 m/s, the fully clad wheel exhibited the lowest drag while at wind speeds greater than or equal to 15 m/s, the racing disc-wheel and the fully clad wheel gave similar drag coefficients. The aero-rim wheel exhibited the highest drag of the commercial wheels at wind speeds greater than 5 m/s.