Try adjusting your valves and see if that helps your engine performance.
Something is not right with the TAV. The cam should always be resting on the buttons.
Here is some good info that should help.
http://www.*****************/asymapp.htm
http://www.key-ideas.com/TC-Sprocket-Change.htm
http://www.diygokarts.com/vb/showthread.php?p=19866
Here's how to remove a governor if you're still interested.
http://buggymasters.com/forum/showthread.php?t=69