I believe you mean quarts, not litres. Tho I like the brits spelling! And the service manual says 4.2. That's where I goofed up; trying to estimate the 2/10 directly from the marks on side of the bottle rather than measuring it first into a graduated cup. That last 'little" splash is what did it.
and for those following, yes, it does shift better. Tho I have no idea how old the oil was when I bought the bike. The nut on the K&N filter is 17mm, same as the drain. And it does run juuuust a little hotter, as was suggested elsewhere. Cheers to all, and ride safe!