The Beach Boys had a right to feel cheated. The Bee Gees were making millions by combining the fabled Beach Boys falsetto harmonies with disco arrangements. Meanwhile the Beach Boys couldn't break into the top 40 with a crowbar.

So ex-Beach Boy Johnston decided to help his old partners cook up a disco single. He dug up "Here Comes the Night," an old chestnut from the 1967 "Wild Honey" album and wrapped it up in 11 minutes of synthesized strings and electric percussion at 132 beats per minute. With the rich Beach Boys harmonies and a strong alto sax solo, it's one of the more appealing disco numbers.

It's also one of the weakest Beach Boys singles ever. This says someting about the relative merits of disco. But it also says something about the confusion currently surrounding the Beach Boys. The group's newest album, "L.A. (The Light Album)" (Caribou JZ 35752), is an insecure effort, groping blindly in several directions for hits.

The Beach Boys have always been misunderstood and underestimated. Now it seems they don't even understand themselves. Instead of relying on their strenghts, they keep trying gimmicks to attract attention.

For example, the Beach Boys are ill - suited to disco, Rod Stewart and the Bee Gees could adapt well to disco because they have a flair for surface style. The Beach Boys' weakness, though, has always been a certain lack of hipness, while their strength has been personal optimism and musical surprises. Disco's technological beat nullifies both the intimacy and the surprises.

When the group takes a hip stance, it always seems awkwardly tacked onto the music. The classical figure in Al Jardine's "Lady Lynda" and the oriental motif in Mike Love's "Sumahara" come across that way. Far more convincing are their child - like enthusiasms - for surfing an cars in their early albums or for Johnny Carson, trees and airplanes more recently.

The ballads by Carl and Dennis Wilson on the new album have a dreamy Beach Boys feel. But they lack the surprising changes and distinctive subtextures of their brother Brian's best work. Carl and Dennis are put in the strange position of being less than successful Beach Boys imitators.

The group's dilemma is the same one they've faced for 18 years. The three brothers, first cousin (Love) and childhool neighbor (Jardine) include four capable harmony singers and one genius. Brian Wilson's Gershwin - like talent is responsible for all the group's successes. Their fortunes ride on him.

Unfortunately, Brian isn't very reliable. Overweight, introverted and deaf in one ear, Brian's personal isolation has produced brillian music. It has also produced several nervous breakdowns. At the height of his creative powers in 1968, but hurt by commercial indifference and personal problems, Brian withdrew as leader of the group.

His output dropped to a handful of songs per album (invariably the best). As a result, the Beach Boys' albums from 1969 to 1976 were uneven affairs with sparkling highlights offset by embarrassments. He turned to the leadership on the 1977 "The Beach Boys Love You" (Reprise MSK 2258), an overlooked piece of powerful primitivism. But with more commercial failure and an unhappy divorce, he's withdrawn again.

He makes only two contributions to "L.A. (Light Album)." Not surprisingly, they're the album's highlights. "Good Timin'," (actually recorded several years ago) is a worthy addition to the tradition of gorgeous ballads like "Surfer Girl." It's no less and no more a throwback to the past than the Rolling Stones' "Shattered."

The folk song, "Shortenin' Bread," is recast completely, just as "Sloop John B" once was. Brian gets a dozen musical activities going at once from the screaming lead guitar to the booming bass vocal to the counterpoint choir. The multiplicity of themes points up the thinness of the rest of the album.

Thus the band's dilemma. They could stop relying on Brian and go on without him. They might make some nice music, but they'd always be haunted by their superior past. They could simply wait and not record until Brian's ready. But that might involve delays of years, which is no way to run an organization.

An example of what solo albums might sound like can be heard on "Celebration" (Pacific Arts PAC 7-122). The group Celebration is led by Mike Love and Beach Boys associates Charles Lloyd, Ron Altbach and Dave Robinson. The group formed around a common interest in transcendental meditation, but lacks the musical inspiration of a Brian Wilson.

Celebration's version of an old Beach Boys song, "Gettin' Hungry," defines the Beach Boys' texture by omitting it. Altbach's "Country Pie" and Love's "She's Just Out to Get You" are likable imitations of Brian Wilson ditties, but clearly imitations just the same. Significantly, the clear highlight of the album is a new song by Brian (co - written with Love, Altbach and Diane Rovell), "How's About a Little Bit."

Dennis Wilson once said: "Brian Wilson is the Beach Boys. We're just his messengers." In many of the past 10 years, the other Beach Boys have stood around waiting for a message to deliver or been forced to paraphrase what the message might have been "L.A. (Light Album)" is a confusing collection of second - hand stories and overdue tales.