Chickenfoot is four songs and "seven pieces of new music" into its second album, according to frontman Sammy Hagar. But he acknowledges there's some concern about keeping that not-so-old gang of theirs together.

The challenge is drummer Chad Smith and his regular gig with the Red Hot Chili Peppers, who are currently writing for the follow-up to 2006's "Stadium Arcadium." "Once they start recording, Chad's never going to be able to get a break," Hagar tells Billboard.com. "If he does, he'll get a couple weeks here, a couple days there, which is not really enough to devote to Chickenfoot. And when they're done with [the album] they're gonna go on the road for a year and a half. So we either have to get a new drummer or wait for Chad...which is unfair to Chickenfoot. It's too good a band."

But Hagar says he, Smith and rest of Chickenfoot -- guitarist Joe Satriani and founding Van Halen bassist Michael Anthony -- are not frustrated by the situation. "We care, but at the same time [Chickenfoot] is not mandatory," Hagar explains. "It's not like we feel like, 'Hey, this is our only chance in life.' Everyone's already been there, done that. Chickenfoot is not our bread and butter, and I think that's really important."

Chickenfoot will play together again on Sept. 10 in Indio, Calif., and Sept. 11 in Stateline, Nev. Hagar says the group had plans to hit the studio after that but things are "kind of up in the air."

However, the frontman is stoked by the material he and Satriani are writing, including the four songs Chickenfoot has already worked on as a quartet. "We probably have a record ready to go," Hagar reports. "It's just waiting for when we can all get together to do it" -- a process also complicated by the Oct. 5 release of Satriani's next album, "Black Swans and Wormhole Wizards," and a three-plus month world tour that starts Oct. 16 in Ireland and comes to North America in December.

Meanwhile, Hagar and his band the Wabos are currently supporting Aerosmith. He has no recording plans of his own at the moment but is working on an autobiography, "Red," with San Francisco music journalist Joel Selvin that he promises will be "really revealing, right down to just about everything you'd want to know" -- including his tenures in Montrose and Van Halen.

"I figure there's only one shot at an autobiography, and you've got to tell the story, as much as it may be painful," says Hagar, who has made two previous attempts at his memoirs. "I really believe there's a lot of people out there that really have no idea where I came from and who I really am. I've never been a press junkie, and I think that's a good thing. So I think the book is going to blow people's minds."