By James Bernard
Updated February 22, 1991 at 05:00 AM EST

For the Knack, 1979 was the Year That Wasn’t. That’s the year this pop-rock quartet’s ”My Sharona” shot to the top of the pop charts. It became a familiar fixture on radio airwaves with its clipped, catchy melody and simple, chest-thumping devotion to a woman with an unusual — but pretty — name. And then, bam almost nothing. Instead of entrenching themselves on the charts, the Knack turned into a pumpkin — a one-hit wonder. People would have made jokes about their plight, except no one could remember their name. But the Knack will not go away quietly. Their comeback album, Serious Fun, their first since 1981, is laden with clever guitar hooks and lyrics about, well, nothing too serious. ”One shot, ecstasy/ Funk house fever’s got a hold on me/Big bang, bedroom scene/Shakedown cruise, on a mean machine,” lead vocalist Doug Fieger announces on the first single, ”Rocket O’ Love.” When the Knack wind such lightheartedness around upbeat power chords and bouncy rhythm tracks they recapture the magic of ”My Sharona.” When they slow down the beat, the album tends to drag. But, luckily for us, they don’t slow down too often. B+