The Beatles jumped the shark w/ "Free As A Bird".
The Who jumped the shark w/ the death of Keith Moon
Led Zeppelin fully jts w/ "In Through The Out Door".
Linkin Park JTS when the band stopped playing Rock.
Nirvana ended b4 it could JTS.
The RHCP have never really JTS, they just don't edit very well & have 2 many samey/filler songs.
Elvis JTS after he returned from the army, albeit I don't think he cared because he got to bang ALL the female leads in his films except Mary Tyler Moore.
The Doors JTS after the band continued when Morrison was dead or whenever u realized that Morrison wasn't spiritual just really high/drunk all the time.
Elton John JTS after "Goodbye Yellow Brick Road".
Michael Jackson JTS after "Bad" even though he still had some good songs like "Scream" or "Jam".
Bob Dylan JTS after "Blonde on Blonde".

Metallica jumped the shark with Bob Rock.
Ozzy jumped the shark the reality series. (Though cases could be made for Zakk Wylde and No More Tears, too.)
Iron Maiden jumped the shark with "No Prayer for the Dying"
Judas Priest jumped the shark with Ripper Owens.
R.E.M. jumped the shark with "Stand."
U2 jumped the shark with McPhisto.
Kiss jumped the shark with " Phantom of the Park"
Van Halen jumped the shark with "Jump" (a case could also be made for the Diver Down album, though)

Green Day jumped the shark when they went from punk to emo (American Idiot) and tried to make themselves more mainstream. I don’t think they’ve ever fully recovered from their emo days and though that album has its moments and they’ve had other decent songs I think that’s their turning point.

I think Red Hot Chili Peppers have jumped the shark too. I think it happened for sure after John Frusciante left the band but I think they were starting to already around the Stadium Arcadium period.

The Who jumped the shark when they continued touring after Entwistle died.
Queen jumped the shark when they toured as Queen with Paul Rogers.
Ozzy's reality show and endless mumbling appearances on Howard Stern jumped Fonzie as he was jumping the original shark.
As much as I love them, Iron Maiden's second life with Bruce Dickinson has been pretty shark worthy. Too many repetitive songs following the pattern set forth in Fear of the Dark. A good pattern, to be sure, but enough is enough.

This reminds me of this thread that I started almost 10 years ago.

That's when they sold out. I said in my thread that the musical term for "Jump the Shark" should be "Dance with Muppets" because of this moment in music history :

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which led to this :

<iframe width="560" height="315" src="https://www.youtube.com/embed/ZXVvvRBBUn8" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>

but the original is bad enough and (to me) the ultimate Jump the Shark musical moment.

Runner up is this :

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Didn't they tour with that dude from American Idol first? That would be their JTC moment.

Weezer has jumped the shark, redeemed themselves, and then jumped the shark again a few times.

The Offspring with Pretty Fly (For A White Guy)

It was long before that. It just took Pretty Fly for people to finally notice.

Weezer has to be one of the top contenders for most inconsistent band I’d say. They’re so all over the place in terms of quality. I’m a fan but it’s hard sometimes.

I disagree. Smash and Ixnay are their best albums I'd say.

agreed

Oh, c'mon. Coming from a long-time Queen fan, they actually jumped the shark with the HOT SPACE album. Starting with that, they lost whatever magic they once had (although INNUENDO wasn't half-bad).

Keane jumped the shark with Night Train.

Stereophonics jumped the shark with "Have A Nice Day".

KISS jumped the shark when they formed.

And personally I thought they immediately got back to normal with The Works and A Kind of Magic albums.

U2 with Rattle and Hum
The Misfits when they started playing without Danzig
Depeche Mode when Alan Wilder left
Van Halen when David Lee Roth left
Rush after Power Windows
Black Sabbath when Ian Gillan left
Judas Priest with Turbo

• The Kinks with the Preservation Acts I & II project.
• The Monkees with the 33 1/3 TV Special... at least until Good Times was released 48 years later.
• Metallica meeting Bob Rock sounds right with me.
• Black Sabbath with Ian Gillen.
• Van Halen with Sammy. Not to say they weren't massively successful, the music just stank. Speaking of which...
• David Lee Roth with Skyscraper. After the brilliant slice of virtuoso hard rock that was Eat Em And Smile, he immediately veered into slick keyboard driven pop/rock/dance. Eesh.
• Chicago after Terry Kath's death.
• Genesis did fine work until Invisible Touch, when they became indistinguishable from whatever Phil Collins was crapping out in the 80s.
• Kiss post Creatures of the Night. Maybe Lick It Up.
• AC/DC with For Those About To Rock. Everything after that album (maybe even including it) was subpar.
• Thin Lizzy with Chinatown. They peaked with Black Rose and everything after that, while it has some good moments, never coalesced as well.
• Iron Maiden with No Prayer for the Dying. They lost something when Adrian Smith left, and while they've had some good (often VERY good) albums since 2000, they've never been as consistently great as they were pre-1990.
• Rolling Stones last high water mark was Tattoo You. Then they plummeted with Undercover. Eesh.

Radiohead - When their studio was robbed and their guitars and drums were stolen.

And KISS really jumped the shark when they went disco.

Does that even count?

The Beatles weren't an actual band anymore at that time. The Beatles Anthology project was really just a retrospective on the band. I'm not sure why releasing a couple of new songs became a part of that project, but the fact that they made the late John Lennon being a required part of any new songs is something that really limited them to just working with some old demos he had made in the late '70s. So both songs ("Free as a Bird" and "Real Love") are actual Beatles songs in a very limited sense (I think of them as little more than outfakes).

No love for Under Pressure?

Certainly The Clash after they fired Mick Jones.

I do still love this album despite its flaws, but it ain't The Clash:

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So true. What a piece of shit that was. My vote goes to Liz Phair with her 2003 self-titled album. Which I didn't think was terrible. It was just too polished and geared to a different audience. And her fan base HATED IT. I personally felt she rebounded slightly with 2005's "Somebody's Miracle". But then came 2010's "Funstyle, which was unforgivable. And she hasn't recorded since.