The frame I built last year uses 650c wheels. You don't see them very often anymore. They used to come on Tri bike, smaller road frames to alleviate toe overlap. The "funny" TT bikes in 80 sometimes used a 650c front wheel. There were a few larger companies that built 650c bikes. I love 650c wheels and if you ever feel like donating them I'll gladly accept them

happy easter
henry