For Daihatsu Copen, aerodynamic tires were developed

Yokohama Rubber introduced the ADVAN A50 tires with improved aerodynamic characteristics, specifically designed for the compact sports convertible Daihatsu Copen. 

Yokohama ADVAN A50 is equipped with 12 aerodynamic fins, V-shaped and located on the outer sidewall, changing the direction of airflow near the tires, reducing air turbulence and improving handling and stability. Additionally, the unique sidewall design is intended to add exclusivity to the appearance of the Copen.

Yokohama has been developing solutions to improve the aerodynamic properties of tires and affect various parameters such as stability, fuel efficiency, and acoustic comfort for over 10 years. For example, in 2011, the company introduced the BluEarth-1 AAA Spec tire with special "pockets" on the sidewalls that reduce air resistance and improve fuel efficiency, and in 2012, a variant with aerodynamic fins was developed. 

"After that, Yokohama Rubber continued to optimize the shape and arrangement of elements that improve aerodynamics, and now we are releasing our first tire with aerodynamic fins," the company says.

The asymmetric tread pattern was taken from the Yokohama BluEarth-A AE-50 tires, and in the Japanese classification system, the new tire received an "A" for fuel efficiency and a "b" for wet grip (using the "AAA-C" and "a-d" scales, respectively). 

The new tire will be available in Japan from September 2024 exclusively through Daihatsu dealerships across the country. Only one size will be available — 165/50 R16.