Hey guys, My fazer 400 clutch slips a little when I pull the machine to high rpm, the engine roar but the speed raise up slowly. I don't know what cause the problem, i have check the clutch disc, but it is Ok for use. only a little black color on one of the steel disc. And I have check the clutch spring, I don't know if it's pressure is still OK for working, will it be the springs pressure problem cause slip? don't wanna waste extra money to buy parts before I find out what cause the slip. Guys give me some tips, thank you very much.