Webbing retractor and method of manufacturing rotation detecting member

In a webbing retractor (10), when a V gear (50) has been rotated in a withdrawal direction following a spool (20) and a W pawl (60) has been relatively displaced with respect to the V gear (50) by inertial force, the rotation of the V gear (50) is regulated and a lock plate (46) regulates the rotation of the spool (20). A first center-of-gravity adjusting hole (66) and a second center-of-gravity adjusting hole (68) are disposed in the W pawl (60), and the sensitivity of detecting the inertial force is adjusted as a result of a center-of-gravity position of the W pawl (60) being adjusted. The first center-of-gravity adjusting hole (66) and the second center-of-gravity adjusting hole (68) are disposed away from an outer peripheral surface of the W pawl (60), so the center-of-gravity position of the W pawl (60) becomes adjustable without having to change the outer peripheral shape of the W pawl (60).