Abstract: A bi-directional torsional coupler for transferring torque from a drive shaft to an integral machine element (pulley, sprocket, gear etc.), comprised of two wrap springs, each having an inner helical spring portion gripping a drive shaft and a coaxial larger diameter helical spring portion, gripping a cylindrical surface of the bi-directional torsional coupler, and surrounding the inner spring, each wrap spring wound in opposite rotational directions needed to grip the shaft to provide torque transfer in both rotational directions. Manual rotation of two end caps of the bi-directional torsional coupler facilitates quick installation, quick axial adjustment and removal from the shaft, by means for unwrapping the inner wrap spring coils from the drive shaft, releasing the torque transfer from the shaft.