I have a 90 model 300 bayou bought new and taken very good care of. Always ran great and has given no trouble. It has developed a knock or rattle at low rpm when under a load. It starts fine and makes no noise at idle or when it is reved up. A frend that's a mechanic said it was the clutches so I had him put new ones in, didn't help. Carb has been cleaned, cdi box checked compression ok valves adjusted,stator checked and nothing helps. I don't know what else to look for. It sounds to me like the spark goes crazy and changes the timing, or like a bad fuel knock. This is a super good machine and has never been abused.I would appreciate it if someone could give me some ideas of what else to look for.
Thanks....Kenny B
