Horny black vintage movie with Billy Counes and Rhonda Jo Petty

Suzy, Denise, and Rhonda are three pretty young ladies in San Francisco who decide to take a bicycle trip to Los Angeles so Suzy can enter in a bicycle race. Along they way, the girls pick up three friendly surfer guys named Mark, Steve, and Charlie. Charlie takes a liking to Suzy, but who is so sexually repressed that she cannot return his affections. However, other complications set in when two degenerate, sex-crazed thugs, on vacation in a traveling trailer, spot the girls and decide to abduct them so they can have their own way with them.