SUMMER OF LOVE: The Inside Story of LSD, Rock & Roll, Free Love and High Times in the West by Joel Selvin (Dutton: $22.95; 384 pp.). It definitely gives one pause--a book entitled "Summer of Love" beginning with the denial that the "summer of love" ever existed, the explanation being that the phrase was invented by glib, Eastern news magazines. The title is just about the only misstep in the book, however, for San Francisco Chronicle music critic Joel Selvin has otherwise written a consummate page-turner, at least for anyone even moderately interested in rock and roll. The story of the San Francisco music scene is a familiar one--the Grateful Dead playing Ken Kesey's Trips Festivals, the Jefferson Airplane living in a Haight-Ashbury mansion, Bill Graham producing everyone at the Fillmore--but Selvin's book differs from most others on the same theme by ignoring everything but the music culture itself. His limited, risky approach pays off, in part because the "psychedelic" music scene merits detailed discussion, but also because Selvin has woven the particulars, old and new, into an engrossing narrative. Rod McKuen recommending the unsigned Airplane to his record label, RCA Victor, and hoping the band would play some of his songs; a charter pilot complaining about the Airplane's cigarette smoke, inspiring Paul Kantner to open a door in mid-flight to throw out his butt; Dead drummer Mickey Hart dosing his horse and dog with acid before dawn rides in Marin County; former actor Graham, years before Ronald Reagan, using a dramatic line from an obscure movie during a heated, public argument--and getting caught; Quicksilver Messenger Service having to edit its dazzling "Who Do You Love" to 25 minutes to fit it onto a record ("Happy Trails"). It's all here, in spades, meaning that Selvin's account of San Francisco's musical glory years is likely to be definitive.