Yesterday i did a controlled experiment with both my 650s. Although one is Pre-Unit and the other Unit they should hold pretty much the same amount though the Pre-Unit does have a little sump and plate whereas the Unit just has a drain bolt. Both run 20/50 Mineral oil with a remote oil filter in the return and both have Morgo plunger pumps. I warmed each engine, rode for 5 miles, left the bike for 5 minutes after switching off and then drained the oil. Pre-Unit 160cc, Unit 120cc.
When i had the problems of the bike blowing oil out of the breather last year i found many people had similar trouble but without these figures it is difficult to know where the problem lies.
So there you are.