Fabian: It's a good question. As I understand it, 26 inch motorcycle wheels are in two primary bead types: (it's difficult, because they use different names in different countries) There was banded aka beaded edge tires that were in use mainly until the mid 1920's. The are now considered dangerous because the air pressure holds the bead to the rim, when the pressure goes low, the tire falls right off. I think this happened on an episode of "What's in the Barn" in a race of 100 year old bikes. The other type of bead is the wire bead, that is harder to get on a rim, but safer. Tell me if I've lost my mind here. You know what, I have a 26 motorcycle tire in the garage, actually I have ones with both kinds of beads. I think I can take a picture....