It must be saturday 1974: Devlin.

"Based on the enormous popularity of daredevil Evel Knievel, Hanna-Barbera developed this cartoon about a stunt motorcyclist working in a traveling circus. Ernie, Todd & Sandy Devlin were part of Hank's circus. Ernie's the motorcycle stunt driver while Todd's his mechanic. An episode of Harvey Birdman Attorney at Law featured a washed-up Ernie Devlin after a child attempted to do a motorcycle stunt in which the boy sued Ernie after being injured."