Hybrids in the 90s were basically like cyclocross bikes, like I said. They had 700c tires, canti's, relaxed angles compared to a road bike and frames that were tougher than a road frame. A road bike will have quicker geometry, less-robust frame, less tire clearance, and side or centerpulls. Don't be confused it's real simple: they're like CX bikes but with flat bars. Google for schwinn criss cross or cross fit, or even Miyata triple cross and you'll probably find a few photos that will illustrate it for you. They make great conversions.