I used to use a tire similar to that when I was going to bike camp in AZ with my Pocket Pocket. It was available as a BMX tire and I am sure I was using 451x1 1/8 tires. 451 rims are used for the younger BMX racers. If you look at a BMX web site you might find more choices. I don't think 1 3/8 tires will fit my Pocket Rocket but I have an early production bike. Roger