ITEM DESCRIPTION: NOS Yamaha RH Engine Crankcase # 122-15121-03-00.
IMPORTANT NOTE: On the Rotary Valve side...notice the hole for the countershaft: You will see two bosses which are blank. Some cases are drilled and tapped some are not. These holes (if your model supports) are used for an oil scoop to feed extra oil to the bushing. If your engine has this scoop... you can drill and tap the case or you can omit the scoop. The last picture shows this setup (picture for reference only).
