The answer is pretty easy to get if you know how high the center of gravity of the bike is from the ground when it is sitting level. With that information and the angle the bike is setting you can determine the lifting force required.
Based on nothing more that a gut feel, I'd guess you are picking up a little less than a third of the bike's weight- or using the numbers above, around 200 pounds. My memory of lifting mine would seem to confirm that's about what it felt like.
The first time I picked mine up (on a lonely country road with no one around in the middle of the night), I had to unload the camping gear before I could budge it. Because of the lift points, anything on the bike contributes DIRECTLY to the lifting force required. (OK- if there are any other engineers reading this, I know that "Directly" isn't quite right- but it is pretty close).
If someone knows where the CG is located, I'd be happy to take a measuring tape and figure the exact force required. Either that or I can get a BIG FISH scale, a couple of pulleys, some rope and a sturdy tree......