Abstract: A derailleur mounting assembly for a bicycle having a rear wheel suspension includes a chain stay having a first end connected to a bicycle crank in a manner so as to pivot about the crank axis, and a derailleur mounted on the chain stay. The chain stay is operable to pivot about the crank axis when the rear wheel suspension allows a rear wheel to move. This allows the derailleur to be maintained in a stationary position with respect to a bike chain extended between the bicycle crank and a sprocket attached to a rear wheel.

Abstract: A bicycle frame with improved rigidity and strength is disclosed. The frame has a truss portion and upper and lower stays for connecting a rear wheel to the truss portion of the frame. One or both of the stays comprise a U-shaped tubular member having a curved portion and two leg portions, the leg portions positioned to straddle the rear wheel, and a second tubular member extending between the truss portion of the frame and the curved portion of the U-shaped tubular member. The second tubular member is shaped at one end so as to terminate in gussets that at least partially surround the curved portion of the U-shaped member. In preferred embodiments, the second tubular member is flattened at the end connecting to the U-shaped tubular member to have an elliptical cross-section with an inside minor axis dimension substantially equal to the outside diameter of the U-shaped tubular member, and the gussets terminate at about the centerline of the U-shaped tubular member.