Technically speaking, retro- is a prefix and not supposed to be used on its own. It means back or backwards. Retro as used on its own nowadays, is short for retrospective which means looking back. So I guess a retro bike would be a bike made to resemble a bike model from earlier years, while a vintage bike actually is from earlier years.
Last edited by Henke; 09-22-07 at 01:33 PM.