Since the bike only holds a little over 2 quarts, most of it is all over the engine. After the ride, put it on the centerstand and give it 20-30 minutes, or till the valve cover is cool enough to keep your hand on it...check your level, then rotate the bike around 180 degrees(facing the opposite direction) and check your level again. Then you can split the difference for a pretty accurate reading.
After you've drained the crankcase, tilt the bike to the right, and you'll see more oil come out(keep the pan under it!). There is a 'lip' inside on the clutch side that prevents all of it from coming out, and then you'll have a drained case. It's not much, but more than you'd think