He called his product, which weighs 18 pounds per cubic foot, ``a true foam, with air bubbles trapped in it''-and the ``first commercially viable light-weight foam fill for tires.'' A polyurethane ...

Add Yahoo as a preferred source to see more of our stories on Google. Foam-filled tires are made of regular rubber but replace the air inside with hardened liquid urethane. While they come with ...

Following is a transcript of the video. Narrator: This is a tire technician disassembling what's known as a foam-filled tire. It's a grueling process, but an important one for these special kinds of ...