Chair back mechanism and control assembly

A chair assembly includes seat support and structures each operably coupled to a base structure, wherein the back support structure is movable between upright and reclined positions, and a biasing assembly exerting a biasing force biasing the back support structure towards the upright position, wherein the biasing force is adjustable between first and second magnitudes, and wherein the second magnitude is greater than the first magnitude. The chair assembly further includes an adjustment assembly operably coupled to the biasing assembly allowing a user to adjust the biasing force between the first and second magnitudes, wherein the adjustment assembly adjusts the biasing assembly between a first configuration corresponding to the first magnitude and a second configuration corresponding to the second magnitude, and an assist feature exerting an assist force on the biasing assembly, thereby reducing an input force required to be applied by a user.