I'm looking at a Kawasaki kfx 400. Its in good condition and has extra stuff, but the guy says it wont shift lower than 4th gear. He said he had a shop look at it and they said it was just the front sprocket being worn down and the chain just isnt getting enough tension. I want to believe the guy because changing a front sprocket is pretty easy, but i dont know if thats the only reason it wont shift. Let me know what you guys think, thanks.