Aftermarket gaskets can kill

I recently sold a carb to Larry in Florida for his CT200 rebuild and he ran across an ugly issue with a previous owner's rebuild. I wanted to put a pin in it, mostly to remind myself not to trust any aftermarket part. Ever.

He's an experienced mechanic, so he tested for oil flow to the top end, and he wasn't getting any.

(The trick to test oil pressure at the top end of these is to loosen the acorn nut from the head bolt. The acorn nut is usually there because the oil follows that particular cylinder stud and a regular bolt would allow oil out.)

After tracking down an oil flow diagram and tracing the path from the pump, he found that he was getting oil on one side of the gasket but not the other. Who knows how long that aftermarket gasket had been keeping oil from the top end.

I'm really surprised there wasn't more damage to the top end, but the rockers just showed a little bit of wear. Perhaps the oil was getting to them via the pushrod channels.

Edit: I came across an NOS ct200 gasket set and I scanned it and posted it here. The last gasket page is the rubber bits and the drain plug washer. Part number 06111-033-000. H/C 23571.