lmfao..mine did it, but it was from the mounting bolt ontop of the head pipe was loose! (like on the fat part of the pipe) and then i had to tighten up the front motor mount bolt and its smooth as cat sh*t now!!
this may be one of those things were by reminding people about it, it makes them think about it. pretty sure they all vibrate, just some more with different things. watch when i get mine fixed its going to vibrate and im going to think i did something wrong when i put it back together.