Patent attributes
A rear bicycle derailleur includes a base member, a movable member, a guide arm and a tension arm. The base member is adapted to be mounted to a bicycle frame. The movable member is movably coupled to the base member, preferably via a linkage, to move between a retracted position and an extended position. The guide arm is pivotally coupled to the movable member around a first axis and has a guide sprocket. The tension arm is pivotally coupled to the movable member around a second axis and has a tension sprocket. Preferably, the guide arm is freely pivotal about the first axis without being rotationally biased, while the tension arm is rotationally biased by a biasing member about the second axis. Preferably, the guide arm and the tension arm are configured and arranged to move independently of each other.
