my 91 650 won't go past 1/8th throttle. it starts shaking and bogging. i checked the carburetor, the reeds, the stator as well as the cdi. i don't know what else the problem could be it runs out of the water after adjusting the carb then when it gets in the water it takes off for about 50 ft and then goes back to the same way it was running before. any ideas would be a great help. thanks