So, finished a ride today with 653 miles on the Z, so drained the oil, whilst performing all other maintenance listed. Installed the new filter, added 1 3/4 quarts of oil for starters to check level. Started it up, let it run a few, waited for the oil level to appear in window, never did. Emptied the 2nd quart bottle in, barely visible at bottom of window. Specs say it takes 1.9 qts with filter change, or 1.8 litre. Has anyone else noticed this? Or have you just filled it until it appears in window? Which is what I am doing, but that means the owners manual and s/m is incorrect. I'm kinda anal about these sorts of things. The service manual says 2.4 qts only when doing an overhaul with dry engine.