I have a Vicma clutch on mine. was really cheap about 28 pounds, With all new lammellers. ( have no idea if thats correct english, But you know the friction plates) and new springs. The old springs was about 1mm shorter than the new ones. But it was slipping as f***.
I heard good stuff abotu the vicma clutch kit. Its supposed to be stronger than the standard. And that it can handle more harsh work with the clutch, like pulling the clutch to wheelie and stuff.