Rivals(1981)

After the death of his father, Adam moves (with his family) from their sheep farm in Wyoming to Los Angeles. Soon after arriving, Adam gets mixed up with Clyde, a mannerless bully who enjoys pulling pranks on Adam and putting him down for his rural image. Adam, in turn, gets back at Clyde on a number of occasions, and the two soon become rivals. When Clyde starts taking a fancy to Adam's sister, and his girfriend starts hanging out with Adam, relations between the two rapidly come to a head.