Add Aerosmith's drummer, Joey Kramer, to the list of public figures who aren't too happy with Justin Bieber. What's his problem with the Canadian wunderkind?

Ultimate Classic Rock reports that Kramer isn't impressed with Bieber's meteoric rise to fame, which started on YouTube and then exploded into, well, everywhere else.

Around 12:45 in the clip above, the rock legend begins his tirade against the pop prince. "He's a product of social media," Kramer griped. "Not because of the quality of his music. The music is secondary."

To be fair to Biebs, the guy does work hard -- he sings like an angel, he dances, he writes, he plays drums and guitar, he's kind to his Beliebers and he tours almost nonstop. Kramer's criticisms seem a bit unfair in terms of artistic merits. However, Kramer's complaints don't end there.

He added, "In the process, he's p---ing in places he shouldn't be p---ing and saying the wrong things to the wrong people. He's a punk."

Well, maybe he has a point about the urination part ... but it looks like Bieber's learned his lesson since that debacle. C'mon, Kramer, give the kid a break!