I think the answer is pretty obvious, just double checking though. if my RM85 cyl. (which is nikasiled) has any, even the smallest of cracks in the plating i need to replate it? no point even trying to run it? the little crack is below all the ports btw, under the exhaust port, and it "Y" shaped, about 1/8" or less in total length.
If the plating flakes off and finds it's way into a bearing it will destroy it pretty quick. Once the plating starts to fail it's best to deal with it.