I was doing a head gasket replacement onnmy 86 Kawasaki ninja gpz1000 and I while cleaning the gunk off the top of the block I noticed a small gap/crack in between two cylinders (Pictures are linked below).
It doesn't go deep, and I don't think it would have an effect in performance or anything since it isn't near any place where fluid could get in, but it wasn't like this between any other cylindera ans I wanted another opinion. Thanks for any help!
It's completely normal, nothing to worry about
It's simply the gap between the sleeves. If you look from above, straight down, you will see a straight edge cut into the outside diameter of the metal sleeves that are pressed into the aluminum cylinder block. The straight edge is there so the sleeves can co-exist in close proximity without encroaching into the other sleeves diameter. They are rarely perfectly aligned because it's not important that they are. The goal is that they can just sit next to each other after being pressed into the block.
This is case on Kawasaki's, Honda's, Suzuki's and Yamaha's going back to their first inline fours in the late 60's and 70's.
It will have no effect on your performance. It's normal.
