bigbangr1

Had the same problem and took it to Yamaha dealer in Australia. Mechanic confirmed it was the camchain tensioner and they replaced it in Jan. No noise since then and the bike seems to respond and perform a lot better too. Apparently there have been a few reported cases here. Mechanic told me that the camchain tensioner may have been a dud or the knocking noise may turn out to be an issue with this model in which case the problem may reoccur. Was told that Yamaha may consider a recall if there are more reported cases.