Can anyone recommend a good clutch for the stock 97cc motor on the racer? I think it is a 5/8 but will any 5/8 fit? Just picked one up real clean starts right up runs great full throttle when you lift the back end up but when you get on it to ride it barely wants to go? Thinking the clutch is shot? Any thoughts? I have a predator 212 going to upgrade to later but going to let my son work with this one to he gets a little older. Also any upgrade mods to the motor available?