There are five large ones and one small one. These dimples are called detent holes. When the transmission is in any one gear, a spring loaded plunger fits into one of these holes, holding the drum in position so that vibration or other forces cannot jar it out of gear. There is one large hole for each gear, and one small hole for neutral. The device that contains the plunger also has a spring, a large-headed hollow screw and a nylon sealing washer. This device is called the detent assembly, and fits into the threaded hole on the lower right rear side of the right engine case (Fig. 28).
6. The shifting drum has four round pegs protruding from its left end. These pegs are called selector pins (Fig. 26). They are part of the means by which the shifting drum is turned.