Originally Posted by ironwood

After 650B rims and tires became more widely available , a few clever cyclists hit upon the idea of fitting wider 650B wheels into frames originally designed for 27' or 700C wheels. I first read about this in a 2004 Rivendell Reader.

I converted a Univega Nuovo Sport to 650B, and think that 650B x 38mm tires are much more comfortable on our broken up lousy roads around here.