I'm afraid you've overfilled your bike. Mine takes 2.8L max if it's drained properly, and I don't even bother checking the oil until after a ride. Especially don't run it on the sidestand, but vertically. Otherwise you get an incorrect low reading.

Every oil-in-the-frame bike I've owned has been the same. No good trying to check oil level until after a ride, wait a few minutes, then check.