Cylinder O-ring question, KZ750 twin

kz750 b4 twin

This is the original coming off.


This is the Vesrah replacement.


My question is, does this o-ring need to be "tucked" into the grove around the barrel? That's what I did. Otherwise it was a little bit loose and I didn't want it to interfere with the gasket surfaces.

I don't think the original was tucked as far down as I mine is. Maybe the original is a little thicker?

I think it is supposed to fit into the groove. I am not entirely sure what that O ring is supposed to seal?

Even though its a tight fit, maybe it keeps oil from seeping between the sleeve and aluminum block...