all centrifugal clutches have some type of springs in them, its to return the shoes when not under power, so that the clutch disengages
They are all also automatic, meaning no shifting.
Most of them all need to have the bushing LIGHTLY oiled, some of the really high end racing clutches, are wet clutches and have a "Shell" around them that contains a bath of oil.
The maxtourge and comet centrifugal clutches are a round drum, with shoes and springs inside, and a sprocket on the back, these can be mounted sprocket towards engine or away from the engine.
Some high end race clutches use plates, and different springs to run and can only spin one way.
To answer your original questions, your max torque is a variation of the centrifugal clutch
=)