I don't understand why some dealers changed out the tensioner while others won't. Last April,09 my dealer made me aware of the Tensioner problem and Yamaha did it out of Warranty at no cost to me. He also did about 25 other sleds before me. I have an 05 RS Vector ER with 5,000 miles. The likelyhood of a tensioner failing is very small but when it is you, it is 100% according to my dealer. A few years ago, Toyota Tacoma 4 cyl had this very same problem where the tensioner failed and the timing chain would cut into the casting and into the water jacket causing anti freeze to flood the engine. I don't think Toyota rushed forward to fix the problem back then. It just seems that there should be some consistancy here and that Yamaha would replace them all. I am very greateful that Yamaha and my dealer did this for me and I wasn't out $700.00.