Maybe one of you can help me by telling me bead seat diameter for the Schwinn 20 x 1 3/8. I have a Schwinn Stardust that was my wife's bike when she was a little girl, the tires are rotten, and I'd like to get the bike rideable for our daughter. The tires are simply marked "20 x 1 3/8 to fit S-5 or S-6 Schwinn Tubular Rim". The front tire also bears the text "Schwinn Sting Ray Fastback", and the rear tire says "Schwinn Fastback Slik". I'd also be grateful if anyone could say whether Kenda or someone else still makes this tire. My Search-Fu is not good enough for me to find this info on the intarwebz.