Well, I asked this question because mine was sitting around 1/2 level in the window, cold. I added enough oil to bring it to about 3/4 level, cold. My experience has been that 3/4 cold will result in about full, hot.
But then I got concerned, because the temps have been in the 20' and 30's, and I haven't ridden for a few weeks. Made me think that adding a little (and it WAS a very little amount...about 2 fluid ounces or so...maybe 1/10 quart) was a dumb way to counteract the boredom of not being able to ride. Worried that it'll be overfull when I get to ride it to operating temp.
That's why the 1/4 inch observation from Rainman was important to me...now I think there'll be no problem.
Just goes to show how not-riding can breed some weird behavior...
The oil in the bike is fresh...oil change 200 miles ago...