I have a stock 03 Z400 with a Renthal chain and sprocket set. I put it on a few months ago. Just the other day I took it out for a ride and the engine sprocket started making noise. I took the sprocket guard off to find that the engine sprocket is very loose as in wobbley. I trid tightening the bolts but it didnt help. I'm no mechanic but I am an amature. I looked in the book but didnt see anything to remedy the problem. Any help will be greatly appreciated.