desmoman900
650 Society Director
Most 650 engines I have worked on has an O-ring between the crankcases on the left side behind the crankshaft including my 75 XS650B. I am currently working on another engine and this one has a plug instead of an O-ring. Take a look on the right side of the photo below and noticed this one has a plug. Anyone can tell me why some engines (same year!) have O-ring and others a plug?
