Originally Posted by Pompiere

This caught my interest because I'm working on a similar bike for my wife. It is a Neroa, made in Japan for domestic sale. It has a front basket with dual headlights and a plastic skirt guard over the rear wheel. The biggest obstacle has been finding new tires. The original tires are marked 22x1 3/4 with no other markings except the maker's name, Riken. I measured the rim (per Sheldon's instructions) and they appear to be 501 mm bead seat diameter. I tried a 24 inch/507 mm kid's mountain bike tire and it falls right off. The closest I have found is a 37-501 wheelchair tire. Although narrower than what I have now, that might be my only option. What size tire is on your bike?