Abstract: A bicycle shock absorption system is provided. The shock absorption system includes a frame having an axially extended bracket portion for coaxially supporting the bicycle's chain wheel; at least one elongate chain stay extending between the bicycle's rear hub sprocket and the frame's bracket portion; and, a revolving shaft for pivotally coupling the chain stay to the bracket portion. The revolving shaft is coupled in coaxially rotatable manner to the bracket portion, and includes a pair of axially offset locating ring portions disposed respectively adjacent the axially opposed bracket ends of the bracket portion. The locating rings serve to stop a relative axial displacement of the adjacent bracket end. The revolving shaft is secured to one end of the chain stay.