The scenario: A 2004 R1150RT, recently purchased new, had the 600-mile maintenance and currently has 4150 miles total. This morning it showed oil about halfway up the sight glass while on the sidestand with a cold engine.
Curious about the actual amount of oil in the engine, I drained it and only got approx. two liters or less. I called the dealer to ask if this wasn't a bit skimpy and could the engine "retain" oil in the cooler or anywhere else. Or could it have used that much oil since the 600-mile maintenance? They said these engines use a lot of oil during break-in period. I knew that, but that much??
Anyway, I replaced the filter and added 3.75L (.9909 gal) and now the sight glass is full of oil top-to-bottom with a cold engine. The dealer recommended draining about one liter, but I don't know about that. The 3.75L is what the manual says.