The clutch comes with a spacer washer that is chamfered on the inside of one side. This spacer goes on the crank first and the chamfer goes toward the engine. The clutch can then be mounted either in-board or out-board using the supplied key and snugged-up with the included bolt and outside washer. DO NOT INSTALL SPACERS TO ALLOW THE CLUTCH TO SLIDE ON THE CRANKSHAFT. This will damage the hub requiring premature replacement. The clutch has plenty of play built in if you use the right amount of internal shims mentioned in the previous paragraph.
Keep the clutch clean. It is ok to spray the entire clutch lightly with WD-40. Lube the sprocket's needle bearings with a drop or two of gear lube after cleaning. Do not get Teflon anywhere near a drum clutch.
The clutch will stall or slip at 3100 RPM and lock up at about 3200 RPM. 3/4" bore x #35 chain.