My 12r has 18-46 stock and a 28.5" tire,that gearing is good for 205mph. I have a few mods done to the bike, it dynoed 175 at the wheel and I removed the limiter(which is set to 186mph) the best I got with a tail wind was 191.4 mph. Some of the anwsers are correct in this post, I need prob another 10-15 hp to break the 200 mark. I was going to try something like that with the Bird but it was going to take to much $. A NOS kit for $400 is prob. the best anwser I could give. But remember you'll prob. only go that fast 2 or 3 times and it will scare the shit outa you. Things happen way to fast at that speed, I'm done with the topspeed runs...