Even if it is stock, a 600 has the most power to weight ratio of any size bike, generally speaking.
You sure about that? The '09 R1 weighs 454lbs and has 180hp - that's 2.52 pounds for each horsepower to move. The '09 R6 weighs 414lbs and has 100hp - that's 4.14 pounds for each horsepower to move - much worse.
First, I said "generally speaking".
Second, I'm not sure of what numbers to believe. SportBike did articles on both those bikes and came up with different figures for HP and weight for the R1. It would be my guess that the 180 figure is measured at the crank. Usually, magazines do a Dyno run to get their own numbers, so I would believe their comparison. They came up with 409.1 lbs, at 100 HP for the R6, while the R1 was 476 lbs, and 146.08 HP. Certainly enough to go against my earlier statement, but not by as much as you would have us believe. Your R6 figures do not change that much, but the R1 drops to 3.26 lbs for each pony to motivate.
It does amaze me sometimes how much HP a transmission sucks up.