Does it sound like it comes from the top near the exhaust valves?  A little bit of tappet noise?

Your bike is just new and not even broken in.  Don't worry about a little clatter.  Big air cooled singles need looser tolerances than liquid cooled multis, too.  Have you had your initial service yet?

On the other hand, maybe your bike is upset with you for using Yamalube, too.  You might need to make it up by giving it a good cleaning and wax job  8)

Do you know who owned the bike originally?  Or the dealership?  Not saying that it might not need some attention, but chances are that it doesn't at such a young age.

Anyway, just kidding.  When I first tried sythetic in my Savage, I used a Kawasaki brand because it was available....but then I experienced clutch slip, which was my bike's way of paying me back