Was wondering whether it's normal for Z to emit some buzzy vibration sound at certain rpm ..mine at around 6k rpm seems to buzz a little which I can't seems to find out where it comes from. Other than that..from 4 to 5 k rpm there's ntg...above 6k it's less noticeable. I read that it's a normal Kawasaki 650 twin thing to buzz a little here and there. Some thoughts would be nice. Ride safe guys.