Lyne attended Southwest Texas Junior College, using scholarships he earned in rodeo events to pay his tuition.
In 1969, when he was a student at Sam Houston State University, Lyne again won the NIRA all-around and tie-down roping titles.
Larry Mahan, the five-time defending all-around world champion cowboy, suffered a broken leg during the bareback bronc riding event at the September Ellensburg Rodeo, eliminating him from title contention.
[3] Lyne maintained a busy schedule; by November, prior to the final event of the season, the NFR, he took part in 112 rodeos, in some weeks entering 3–4 competitions.
The pair's efforts to win the title were documented in the film The Great American Cowboy, which won the Academy Award for Best Documentary Feature.
[11] By the NFR, Lyne had wrapped up his second consecutive all-around cowboy and tie-down roping world championships.
As of 2019, he was one of three cowboys (along with Ace Berry and Don McLaughlin) to win multiple event average titles at an NFR.
[14] The bull riding average championship at the NFR helped Lyne finish second in season earnings for that event.
[16][19] After the 1972 season, Lyne retired from rodeo competition,[8] as he decided to raise his daughters on his family's Texas ranch.
[24] Samantha, a former Women's Professional Rodeo Association (WPRA) barrel racer who qualified for the 2014 NFR, is married to famous former bull rider J.B.