Like YMracing said it depends on a lot of factors. I went there in October on my 09 750, I weigh 285 pounds and am on a bone stock bike (with a likely tired engine) I was told that the suggested gearing to run is 16/42 to start, if I was fast go to 16/41, and if I was stupid fast and light go 16/40. I didn't have any rear sprockets that small so I just took those ratios and played around with them. Ordered an 18 tooth front sprocket since they're cheaper than a rear and then I could just run the rears I already had, but an 18 tooth front sprocket won't fit, it hits one of the mounting points for the sprocket cover. Ended up finding a used 43 and 42 tooth rear sprocket, and ran 17/43 all weekend. That was likely overgeared for my pace, as I was only ever pulling the top of 5th, but being my first time there I still ran 2:03's by my first race, and finished 8th out of 16 in the heavyweight SS.