Tim Boyle, Don Ipock and Gary Bonacker sit on the summit of Mt. Bachelor in 1976 with their “Klunker” bikes, an early, one-speed version of a mountain bike.

Tim Boyle, Don Ipock and Gary Bonacker sit on the summit of Mt. Bachelor in 1976 with their “Klunker” bikes, an early, one-speed version of a mountain bike.