Red Hot Chili Peppers fans can be chopped into a sort of pico de gallo . There's the rare but quintessential fan who loves all Peppers music – every song, every album, all the way back to the group's self-titled debut in 1984. There's the 21st-century fan – the mainstream consumer who accounts for the platinum success of the Pepper's new double-CD, Stadium Arcadium , but has never heard 1987's fiery breakout, The Uplift Mofo Party Plan .

Lastly, there's the stubbornly reminiscent Gen-Xer: The 30-something who wishes the Peppers had never tugged off those infamous socks. He still rocks to his Peppers mix CD, which includes funky blasts from albums up through 1989's Mother's Milk, ” perhaps even 1991's Blood Sugar Sex Magik , but nothing after. Too commercial.

Red Hot Chili Peppers singer Anthony Kiedis can empathize.

“I understand that,” Kiedis says, phoning from his home in Los Angeles. “I don't really fall into that category myself. The thing I've noticed about our fans that makes me the happiest is that they come in all ages. Literally, we have kids standing on the side of the stage that are 5-years-old. And they're watching Chad Smith play the drums, and they're just dumbfounded and amazed, and they're absolutely entranced. And then there's their big brother or sister that love our music, and they're out there dancing. And then there's like the mom or dad that brought them, and they're feeling it.

“I think that's kind of the beauty of our pico de gallo , at this point – that it covers all ages including really young, smart, cool kids that are, like, tapping into the new [music]. They're still tapping into us and our new [music]. So it's fine if people want to stick to our body of work from the '80s. We're proud of that music and if that's what suits them, that's fine. But thank God that there are these people that are interested in new music, that like what we do now.”

Stadium Arcadium debuted at No. 1 in 28 countries, including the United States. The Peppers recently enjoyed a sold-out tour of Europe, played the Fuji Festival in Japan and rocked a headlining slot at Lollapalooza.

It's crazy stuff for a band that built its foundation on party rock – an inventive but often immature vibe that blended funk, punk and rap. Early on, the Peppers became notorious for performing naked and placing socks over their privates. This was not a group that anyone expected, or wanted, to see reach middle age.

But here is Kiedis, who will turn 44 in November, talking about the prospect of a long and prosperous future. His steady growth from rapper to singer has been a driving force in the band's evolution into a mainstream radio success.

“We don't want to be same as we were in the '80s or '90s,” Kiedis says. “We keep changing and doing something new and interesting, and there always seems to be an audience for us with the new music that we make.

“… Really, the only thing that's the same about this band is the sort of spirit of the band,” Kiedis says. “The experimentation and the music is constantly changing, but we're true to the spirit that we began with. ... The spirit has not died. It's just, the things that that spirit has to offer have changed along the way.”

Considering the Peppers' rocky history, it was inevitable. Drugs, particularly heroin, have tormented this group since the beginning. The Peppers' original guitarist died of an overdose in 1988. His eventual replacement, gifted musician John Frusciante, struggled to the point that he was out of the band for more than half a decade. Kiedis also has battled heroin, as documented in his memoir, 2004's Scar Tissue .

Despite buddy-buddy lyrics about the musicians' love for one another, personality clashes have challenged this band, too. During interviews to promote Stadium Arcadium , bassist Flea revealed that he almost quit the Peppers because of a beef with Frusciante during the recording of 2002's album By the Way .

“The Flea thing, quitting the band, I don't even know why he would say that to the press,” Kiedis says. “Even if he was feeling that way – what right is it of the public to know that? That's a thing that Flea was going through, a thing that Flea and John were going through. They've worked it out since then.”

So is it really that hard to be a Chili Pepper?

“Most days it isn't,” Kiedis says candidly. “But there are a lot of sort of sensitive, delicate artist types that can have a bad day and can feel like something's not working out. If it doesn't get communicated, it'll fester and boil for a while. To me, and from what I see around me, everybody absolutely loves and enjoys doing what they're doing in this band.”

The Chili Peppers will tour the United States this fall with their friends, psychedelic rock act the Mars Volta, opening shows. Setlists will include plenty of modern hits, but long-time Peppers fans undoubtedly will be treated to select college-rock classics.

Kiedis might even take his shirt off. In fact, he says, there will never be a day when he feels ridiculous taking his shirt off.

“No, because why would I? Even if I'm an old man with wrinkling, sagging skin, I would still take my shirt off because I still want to be able to jump in the ocean. I still want to be able to howl at the moon and dance around. That's just good livin'!”

But let's be clear: Good livin' is not the same as entering an '80s time warp with the grown-up Red Hot Chili Peppers, as evidenced by Kiedis' response to one last inquiry.

After all these years, does the sock still fit?

“What an absurd question,” Kiedis says.

© 2006, The Idaho Statesman (Boise, Idaho).

Distributed by McClatchy-Tribune Information Services.

Stadium Arcadium is currently available. The band will perform Aug. 31 & Sept. 1 at the Forum, in Inglewood. For more information, visit www.redhotchilipeppers.com.