I am using a stock front with a 40 rear on 17" Warp 9's with Shinko 006 Poldium tires. Less than 1/4 throttle 70MPH
On the go kart track i found the 15 44 to be quite tall. hitting 80mph on the straights and only using into 5th. I think I could go 14/44 or 13/44 at sonoma and be better off. It really spending too much time pulling individual gears out of corners instead of slamming 3 gears to the next....
I went up 2 or 3 on the rear sprocket ... whatever size I could get in there without having to change the chain. We do a lot of slow speed stuff and NEVER go anywhere near a highway so it made sense to gear the bike down a bit.
stock front with 40 tooth rear. I miss that aggressive jump n snap it used to have but because this bike will be 95% street it made sense to go lower. A lot smoother and gears last a lot longer, just doesn't have that wheel lifting grunt anymore. Plus these warp9 rims are pretty heavy. I think next time i would like to try a 44 or 45 tooth rear.