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Bridgestone Corp developed the second generation model of its air-less tire by improving load capacity and travelling performance and reducing rolling resistance and exhibited it at the 43rd Tokyo Motor Show 2013.

The company showed the first generation model in 2011 (See related article). The tire does not need to be filled with air. Therefore, it eliminates the need to worry about a puncture and saves maintenance costs. While the first generation model supports a vehicle mass of 100kg and maximum speed of 6km/h, the second generation model supports a vehicle mass of 410kg and maximum speed of 60km/h so that it can be used for ultra-small vehicles.

For the material of its spokes, Bridgestone employed a strong, soft thermoplastic resin. Also, the company improved the design of the spokes by using FEM (finite element method) simulation to reduce stress and strain in the tire.

About 90% of the tire's rolling resistance is accounted for by energy loss caused by the tire repeatedly changing its shape. This time, Bridgestone drastically reduced the energy loss by employing new materials and simplifying the tire's structure. As a result, the rolling resistance of the new model is equivalent to that of the company's air-filled fuel-saving tire. The resin and rubber used for the spoke and tread, respectively, are recyclable.