Abstract: A pivot joint for a bicycle frame is described, which includes an inner bearing sleeve concentrically disposed within an outer bearing sleeve. The inner bearing sleeve has an outer bearing surface in rotatably sliding contact with an inner bearing surface of the outer bearing sleeve, such that the inner and outer bearing sleeves are rotatable relative to each other about a central pivot axis to permit relative rotation of the components joined by the pivot joint. Each of the inner and outer bearing surfaces includes a substantially axially extending region and at least one angled bearing region that defines an angled raceway surface thereon. The angled raceway surfaces are disposed at an angle relative to the central pivot axis and meet in bearing engagement with each other to define a slip plane disposed at the same angle.

Abstract: A bicycle rear wheel suspension system includes an upper link and a lower link both pivotally attached to the frame and to a rear stay member. An instantaneous center of rotation of the rear stay member is defined at an intersection between an upper axis extending through first and second pivots of the upper link and a lower axis extending through third and fourth pivots of the lower link. Throughout a travel distance of a shock absorber of the suspension system, the instantaneous center of rotation remains below an average chain torque line of the bicycle, the lower axis remains above an axle axis extending through the rear wheel axle, and a portion of the lower axis defined between the third and fourth pivots extends below the average chain torque line.

Abstract: A bicycle frame set comprising a main frame and a rear wheel suspension system including a swing-arm, a first link member and an intermediate lower link member. The swing arm has a forward end pivotally connected to the main frame. The swing-arm pivots such that a rear wheel axle on the swing-arm pivots about the lower pivot point on the frame with a constant radius of rotation. The first link member is pivotally connected to the main frame at a link pivot point, and has a displaceable lower end pivotable about the link pivot point. The intermediate lower link member is pivotally connected between the first link member and the swing-arm. The first link member rotates in a direction opposite to the rotation of the swing-arm as the suspension system compresses. A shock absorber is disposed between the first link member and the main frame.

Abstract: A bicycle frame set comprising a main frame and a rear wheel suspension system. The rear wheel suspension system comprises a first link member with an upper end pivotally connected to a seat tube of the main frame at a link pivot point located rearward of an axis extending between a bottom bracket of the main frame and an intersection of the seat tube and a top tube of the main frame. The first link member has a displaceable lower end pivotable about the link pivot point. The swing-arm is pivotally interconnected with the main frame proximate the bottom bracket and has a rearward end adapted to engage a rear wheel axle. The swing-arm is pivotally connected with the first link member at a point thereon intermediate the upper and lower ends. A shock absorber is affixed between the main frame and the lower end of the first link member.

Abstract: A junction for the head tube of a bicycle frame with top tube and down tube members is fabricated in such a way that the top tube and down tube members are jointed. The method of mitering the top tube and down tube members to form the requested joint is cutting off a portion of walls of both the top tube and down tube members at the head ends to form a miter joint. The method of mitering provides for optimum contact area and ease of manufacturing, especially for tubes with non-traditional cross-sectional shapes.