2008 busa with 56k miles, problem is when im road racing.

The bike in 3rd gear& [email protected] takes off FullThrottle with all power. however, when rpm reach 6000 to 8000, the bike feels lose of power, (g-force stalls) but when the rpm reach 9000 to 10.500rpm the power g-force comes back. Then it happens the same way in each gear.
(Bike still pulls but [not as hard] between 6000 to 8000 rpm)

Any suggestions will be greatly appreciated