Patent ID: 7566066
Filing Date: 2009-07-28
Classification: B62K

Abstract:
1. A bicycle suspension system comprising: a front frame; a rear frame adapted to support a rear wheel, a lower link pivotally connected at a first end thereof to said front frame and pivotally connected at a second end thereof to said rear frame, and an upper link pivotally connected at a first end thereof to said front frame and pivotally connected at a second end thereof to said rear frame; a drive unit having a chain, a crankshaft mounted directly to the front frame, and a driving sprocket; and a shock absorber configured to absorb shock applied to the front and rear frames during a compression stroke; wherein the front and rear frames are arranged to guide a virtual pivot point, which represents a rotating center of a hub axle of the rear wheel when the rear wheel moves upwardly relative to the front frame, to move from a first position, which is located rearward of a center of the driving sprocket and adjacent to a junction between the chain and the driving sprocket when the rear wheel is disposed at a normal position, where a substantially horizontal line extends between a ground contact point of the rear wheel and a ground contact point of the front wheel, to a second position that is rearwardly spaced away from the first position when the rear wheel moves away from the normal position; and an intersection point of a first line passing through said first and second ends of said lower link, and a second line passing through said first and second ends of said upper link, wherein a line interconnecting said intersection point and the ground contact point of the rear wheel forms an angle of about 40° to 50° with respect to the horizontal line when the rear wheel is disposed at the normal position.