Patent attributes
A shift drum apparatus is reduced in weight relative to conventional shift drums. The shift drum includes a shift fork, a shift drum main body, and a lid member. The shift fork is slidably mounted on a shift fork support shaft. The shift fork changes a gear position of a transmission mechanism. The shift drum main body is formed into a hollow cylindrical shape. The shift drum main body has an end face on a first side thereof in a cylindrical axis direction that is open to form an opening portion. The shift drum main body further includes a cam groove formed on an outer circumferential surface thereof. An end portion of the shift fork is fitted in this cam groove to allow the shift fork to slide. The lid member is disc-shaped and mounted by being press-fitted in the opening portion of the shift drum main body.
