When it came to gaskets, I prefer sticking to OEM ones, at least in key places like cylinder base or under cylinder head. So no wonder I’ve bought OEM cylinder gasket for KZ650 engine. Its part number is 11009-046 and it’s not available in large webstores like Partzilla or CMSNL, but it still might be found on ebay and in smaller webshops.
I had a plan B for the situation: to use aftermarket cylinder base gasket. In combination with sealant rubbed in gasket, it would work. Nevertheless, when I got a nick of time I did the search and found out that 11009-046 wasn’t the only OEM option for KZ650 cylinder base gasket. In fact it was superseded with 11060-1362. I found and bought this newer gasket and here how it looks: