All the edges look square to me...i.d and o.d. the only difference I see is that one side is convex and the other concave. This of course from the dogs? beating against it causing it to form into the beleville. It actually looks more like a bellville spring.
I think Fred (Rocket Scientist) is refering to the circlip ring and which way it is on the shaft as there is a slight rounded edge on one face and the other face has sharper edges
I really can't tell unless it's the side that is buggered up from the splines in which case it would be the side facing away from the gear. inside diameter or outside diameter?
I can see the chamfor in your picture but I don't see one on mine. If this is correct then the situation is even MORE DIRE. Holy crap! the thought that a tiny groove and a 1/16" wide piece of metal is all that holds these gears in place is sobering.The circlips are a stamped part. As it is manufactured, it pushes through a die. One edge is rounded, the other edge is sharp. Third and fourth gear sit back to back on the shaft with circlips on either side. The sharp edge should face away from the gear. Here is my failed clip, you can see the rounded edge was facing away from the gear (incorrectly). Because the rounded edge acts like a chamfer, when side loaded, it tries to climb out of the groove. Over time it weakens it enough where it finally comes out of the groove.
