STEVE TESICH IS a master of the "sleeper" film. Such past screenplays of his like Breaking Away and Four Friends overcame lukewarm box office receptions to become favorites on TV and cable. Tesich writes movies that are humanly endearing that grab an older audience even if they leave the Rambo crowd unflexed.

Unfortunately, American Flyers is probably not going to make it big with anyone. The problem with the movie is mainly one of genre and not of creative effort. American Flyers suffers from Brian's Song syndrome, a crippling disease in today's market. The familiar symptoms run like this: The Sommers family, divided against itself since the death of the father, is pulled together by the impending death of a son and a bicycle race, which races in the same sense that Ed Koch whispers.

Tesich manages to breath some new life into this old victim, however. The mood throughout the movie is sincerely joyous, not the usual frantic desperation of a terminal groping at a little more happiness. And a very clever twist in the plot manages to shake the viewer up considerably.

The highlight of the film is the characters of the two brothers. Tesich is always makes up for what he misses in plot with character and dialogue. And Kevin Costner and David Grant bring Tesich's script to life in a realistic and talented manner. One can actually believe, or at least hope, that if someone close were dying, one would act like these brothers.

ONE CONSISTENT weakness in Tesich's films is his portrayal of women. They have no more character than the bicycle spokes, serving archetypical and sexual purposes without assuming any form themselves. The women in this film, such a Rae Dae Chong as Costner's lover, are trapped in Tesich's unliberated script.

Perhaps Tesich and director John Badham tried a little too hard to reach; the younger set in this film. The soundtrack is composed of insipid, topical songs that should have been replaced by something with a little guts, like "Carmen" or "Georgia," even at the risk of not being able to sell the record to youngsters. The focus on the younger generation is stronger than in other Tesich films, with middle age characters seldom making any appearence except in two dimensional form. This gives the film the surreal aspect of other movies aimed at teens. After all, the whole world is not composed of the proto-and nouveau yuppie.

Given that there is much to be criticized in American Flyers, it is one of the few films this year, besides Kiss of the Spider Woman, in which there are signs of intelligent life in the script. A visit to this film is a necessary, if not completely ecstatic, experience.