So, after replacing the hes and throttle cables and doing a couple sync's I heard a weird sound while at revs finalizing the last sync and then bike was running a little rough. I read up a bit and found that a critical update is the left side cam chain tensioner. So I stopped riding it until I picked up a new one today from bens in watsonville, ca. Ben was surprised the bike made it 84k miles on the original. The rails have not failed and the new tensioner is in but is it possible they could still fail? Should I just replace them?