centrifugal clutch

A while back I tried to build a 2 speed manual trans for my 79cc bike, I have since scrapped the idea. I want to build a 2 speed auto instead, but I really have no idea how to go about doing it. I have seen pictures of them made using 2 centrifugal clutches, but don't know how to do this. Can...

So I got this kit. The engine came with a centrifugal clutch and pull start already installed on it. What I want know is this: How the do I remove the centrifugal clutch? I've looked everywhere and can't find a solid answer.