HAIR HAS ALWAYS been intimately associated with rock 'n' roll, from the Beatles to Bon Jovi. Just ask Jon Bon Jovi, who has recently returned from a four-year hiatus with a hit-packed new album called "Keep the Faith," and a sleek, shorter new haircut that's been attracting more media attention than any of his songs.

"I always thought if I wanted some press, I had to go out and work for it," Bon Jovi says on the phone from his Philadelphia hotel SPOTLIGHT room. "I had no idea that all I had to do is go out and get a haircut. It's gotten more attention than Elvis cutting off his sideburns! I just gotta laugh it off, it's not like a case of Samson or anything."

With his MTV-friendly face and leonine locks, Bon Jovi epitomized the look and sound of the '80s, Metal Lite, selling more than 30 million albums with glossy, punchy hits like "Living On a Prayer" and "You Give Love a Bad Name." And when Bruce Springsteen split for Beverly Hills, Jon Bon Jovi -- formerly John Bongiovi -- became New Jersey's de facto resident superstar. Then in 1988, at the peak of fame, Bon Jovi abandoned the faithful for five years.

"It was a layoff," says Bon Jovi, 30. "Wait -- no, that's the big bad word for the '90s. Let's call it a hiatus. The hiatus came after five consecutive albums and four consecutive tours. And then there was sort of a fifth tour -- I went out as a guitar player with Southside Johnny, because I was having withdrawal symptoms. That's the life man, being a player, just laying back, play guitar, keep a drink on your amplifier. Right back to the bars again, that's the way to do it.

"With Bon Jovi," he says, pausing for a gulp of the Jolt cola he's addicted to, "things were unbelievably good on a success level, but there wasn't a lot of personal satisfaction at the end of the day. And that's a scary thought when you're thinking, 'We're the number one everything, selling out every building in the world, but we're not happy.' So we had to take a step away to reassess that."

So during the past four years, solo albums were made. Guitarist Richie Sambora, he of the tabloid-fueling romance with Cher, did one called "Stranger In This Town," and Bon Jovi did the soundtrack for "Young Guns" with Elton John and Jeff Beck, scoring a No. 1 single and satisfying his western fascination (he's got another song on his desk for an upcoming cop movie with Gary Oldman). He did some producing, putting together a song for Hall & Oates and one for Stevie Nicks. He took one of his Harleys on a two-month cross-country motorcycle trip, spawning the song "Dry County" on the new album. And he got married in 1989, to longtime girlfriend Dorothea Hurley, a New Jersey green-belt karate champ -- they're expecting in April. He still lives in Rumson, N.J., where his mom runs the band's fan club.

"When we got back into it was with a renewed sense of purpose," Bon Jovi says. "We're pacing it a lot better. We're a workaholic band and in the past we would have run right out on the road the day the record was released. This time, it was November when we released the record, we stayed home for the holidays, we did the two videos from Jersey -- it was better paced. I hope that we don't just fall right back into that. In fact, I just had a talk with our manager, arguing for a 10-day break, which we never used to do before.

"Where we usually took three months to do a record, this time we took six. The attitude was to push the boundaries, not jump on our previous success, or the current fads and fashions."

But the decade had changed, and the look and sound of rock music had changed with it -- "authenticity" is now prized over glamour, and a lean, live bar-band sound is more valued than stadium glitz.

"I don't know that I felt we had to be a new band, as much as I wanted to be a new band," Bon Jovi says. "You know, 'You Give Love a Bad Name' and 'Living on a Prayer,' and so on, they were all Number One songs, sold lots of records, but that was then and I don't care to write that song again. So instead of making it safe, I said 'Let's push it.' "

Bon Jovi says his favorites on the new album are the confessional, piano-driven power ballad "Bed of Roses," and the 10-minute recession epic "Dry County."

"Instead of writing on the guitar, playing guitar, living with my guitar, I sat down with the piano," he says. "And instead of playing with two paws," he laughs, "I spent some time taking a few lessons. And it really opened me up -- 'Dry County' is evidence of that. I would have never written a song like that before. It was definitely influenced by the bike trip. I just said, 'Damn the torpedoes, I think there's something to say here.' These guys in those Texas oil towns, like Abilene and west of there, what they're going through was paralleling my own life in a funny way. They had sacrificed a lot in order to take that gamble on the pot of gold. And I sacrificed youth and friendships . . . to leave everything and sold my soul for this damn band and was unhappy with it. And I said, 'This isn't fair is it?' So I had to reassess the situation to see if I cared to do it anymore."

That unusually long song occasionally turns up in the current Bon Jovi concert tour. "Last night I didn't want to do it," Bon Jovi says. "I could never do the same set every night. The stage is more simplistic this time out. I'm not flying around anymore, I don't have the catwalk that comes out of the sky anymore. It's more back down to songs. There's six albums worth of material here, and we're playing some of the 'Young Guns' stuff, as well as whatever covers I'm in the mood to do. Last night in Philadelphia we did 'Shout!,' which I've been having a lot of fun with. We did 'I Can't Help Falling in Love With You'; we did 'Slow Down' by the Beatles -- the night before we did 'A Little Help From My Friends.' However we're feeling, we go for it."

BON JOVI -- Appearing Saturday at Capital Centre. Call 202/432-7328. To hear a Sound Bite from "Keep the Faith," call 202/334-9000 and press 8101.