IT'S HARD to believe that Tipper Gore and her Big Brothers find Motley Crue a threat to western civilization. After all, this L.A. heavy-metal band is just a cartoon of a rock group: empty-headed clowns having a lot of fun very loudly.

Their new album, "Girls, Girls, Girls," provides a lot more fun than their previous three, thanks to a new emphasis on singalong melodies and boogie rhythms, and the title song has put the notorious glam-rockers into the top-10 singles chart for the first time. The lyrics are offensively sexist, but everything about the album is so calculatingly stupid that the band poses no more threat to anyone than an all-night frat party.

By contrast, "Whitesnake," the self-titled second album by the British hardrock band led by former Deep Purple vocalist David Coverdale, is so humorlessly self-important that it's not much fun at all. Coverdale's tonsil-twisting screams and John Sykes' muddy power chords all come off as tired, second-rate imitations of Led Zeppelin, and Coverdale's pseudo-profundity makes the dumb lyrics all the more annoying. MOTLEY CRUE --

"Girls, Girls, Girls" (Elektra 9 60725-1).

WHITESNAKE --

"Whitesnake" (Geffen GHF 24099).

Both appearing Friday and Saturday at the Capital Centre.