Grooves in the basket and inner hub. That bike is used, I would check what springs are in there, or just replace them. Blue plates, mike the fiber plates and metal, inspect the pressure hubs, where the plates ride for ridges. Make sure your cable is good and properly routed. If it has aluminum plates, I would scrap them and get steel. If you have a fat bank account, get the wiseco basket with hinson hubs, Honda makes the best plates. You could get some beefier springs, and run a hydraulic clutch. I believe that covers it,