Guys the valve guides,seals and exhaust valves have all been replaced.When they cranked it up it had a rattle to it.I didn't hear it cause i wasn't there but they told me the cam chain tensioner needed to be replaced,they did that last week and I checked on the bike last saturday and they told me that the bike still had the same rattle and yamaha told them to replace the cam chain.Now i'm waiting for that part and who nows whether that will correct the problem.
My question is did they screw something up when they did the initial parts replacement?
If indeed it is the cam chain tensioner, it is very easy to diagnose once removed, it either works or it doesn't, simple.
Other than that, it's really difficult to answer these concerns. The only indication from the outside listening in is where the rattle sound is coming from. Even then, without a strip down to check dimensions, you will not know for certain. All I know is, once the work has been done correctly, the motor will be silent and it will run like a champ.
I found myself in a very similar situation to yours, except my original dealer didn't give a rats ass. At least yours is reporting odd sounds back to you. For now, hold tight and give it some time to let things work themselves out. Yes it will test your nerve, as it did mine, but it sounds like your dealer is trying to do the right thing.
After you get it back, if things are not well with your engine, IMO you will have to
seek out a 5 star Yamaha dealer like I did. It makes a HUGE difference when you have complete confidence in your mechanic and dealership.