I am thinking of faking together a set of wheels for an old Schwinn Fastback, which uses 20 x 1 3/8 tires with an ISO of 451. There is apparently a BMX rim size used for beginning racers called Mini BMX, which is available in 20 x 1 1/8 or 1 3/8 and also has an ISO of 451. (Doesn't make a lot of sense to me, as standard BMX wheels with 20 x decimal measurement wheels have an ISO of 406. Why would you put a smaller rider on taller wheels? Whatever, if Sheldon says it, then I believe it.) At any rate, I'm thinking of lacing a set of these to old Schwinn hubs. Does anyone have any experience with this size BMX rim? Does it sound like it'd work for what I'm trying to do?