hey i just bought my cbr1000rr this week great bike but not much low end power. but i will say after it hits 3000rpm its crazy fast. im tryin to improve on that i was just thinkin bout changing the rear sprocket. i was wondering if anyone had any input on what size... i heard 42 in the rear would be a good choice... or should i just get a 520 conversion,

 

15 front and 42 rear for track and 16 front 42 rear for street. 06 model comes with stock 42 at rear. you will also need a SpeedoHealer or your odo over reads the mileage done quite substantially and the speedo will also be out.