The First Suspension Mountain Bike

Offroad Bicycles was the first companies to market suspension frames as a complete bike. In 1990 the Pro-Flex model was introduced. The bikes were designed by Bob Girvin and build in the USA by Serotta. The bike uses elastomer in both the Offroad Flexstem and the rear end to "suspend" the rider. The Offroad name was dropped in favor of Proflex in 1994, and eventually the company became K2 Bikes.

While farily rudimentary by today's standards, the Pro-Flex was cutting edge at the time. Besides the monostay rear suspension, the bike had elevated stays and full Shimano XT components. Front and rear travel are likely both measured in fractions of an inch, but in 1990 that was more than anyone else had to offer.

I was told there were only 125 of these frames built, so although it was the first production suspension bike, it was rather rare on the trail. In the following years Offroad went on to specialize in full suspension bikes, with updated versions of this frame.

-el