“Pump it up? You won’t really need to, soon. Bridgestone has revealed a new “airless” bicycle tire that it plans to put on sale by 2019. The non-pneumatic features a ring of flexible composite spokes — connected to a smaller, solid inner hub — that both hold its shape and provide cushioning on par with an air-filled tube. A conventionally-shaped tread is mounted to the outside. Bridgestone has been developing “tweels” intended for automobiles for several years, but has yet to commercialize any of the designs. Polaris currently sells an ATV with flat-proof tires of a similar design that’s available to military and consumer users, while Michelin offers one for small commercial vehicles. Projected pricing and size availability for the Bridgestone bicycle tires have not yet been determined.”