has a pretty loud rattle and not much power especially at the lower rpms but also at higher rpms. best speed is between 5-7 grand. then when i turn it off for probly less then a second after the engines stopped i can hear somthing spin to a stop inside (is that normal?). the motor seems to be getting hot quick also. ive been messing with the carbs alot and the fuel mixture. one and a half seems right on one carb 2 turns on the other. any ideas on the rattle or any other of its problems? would getting new carbs be a waste of time with this rattle?

sounds like you are running really lean-  the ratlle may actually be pinging.  pinging is bad it can eat pistons and rings.  check your plugs to see what they look like.  also check your air filter to see if it is dirty.  running lean will make it run very hot and is very bad on the engine..