Leonard won the first A.M.A. Grand National Championship Series in 1954 and won it again in 1956 and 1957.[2] His record totals 27 wins, including the 1957 and 1958 Daytona 200.[2] He also resulted vice-champion in 1958, 1960 and 1961, third in 1955, and fifth in 1959. He retired from motorcycle racing at the completion of the 1961 season and turned his attention to auto racing. He was also a member of the AMA (American Motorcycle Association District 36) Sanctioned San Jose Motorcycle club (The Dons) which includes such famed alumni as Sam Arena, Tom Sifton, Kenny Eggers and Sam Arena Jr.
Leonard returned to Vel's Parnelli Jones again in 1970, working with famed chief mechanic George Bignotti. In his first race of the year, the Indianapolis 500 he drove the #15 Johnny LightningPJ Colt-Ford. In the race Leonard qualified in 18th place and was soon running in 2nd place to teammate Unser. Leonard's engine quit after 73 laps and he could only finish in 24th place. It was discovered post-race the engine switch had been flipped, meaning that there was nothing wrong with the engine and that Leonard could have continued. Leonard then competed in the Rex Mays Classic at Wisconsin State Fairgrounds Park Speedway where he only led the final nine laps on his way to his first victory since 1965 at Milwaukee. Leonard started one more race that year, the California 500 at Ontario Motor Speedway, where he qualified in 6th place and finished in 13th place after spinning out. Leonard finished the season 32nd in points.
At the Indianapolis 500, Leonard battled with teammate Unser for the lead. Leonard eventually led for 21 laps before retiring with a broken turbocharger. Leonard then got back-to-back second-place finishes at the Rex Mays Classic 150 at Wisconsin State Fairgrounds Park Speedway and the Pocono 500 at Pocono International Raceway; in the latter Leonard battled with Mark Donohue for the win, until Leonard stretched his fuel hose during his final pit stop. Leonard won the California 500 at Ontario Motor Speedway. Leonard clinched the championship at the next to last race of the season, the Trenton 300 at Trenton International Speedway, with a third-place finish.
In 1973, Leonard returned to Vel's Parnelli Jones, driving the #1 SamsoniteParnelli VPJ-2-Offenhauser. The season was a struggle for Leonard as he could only get a best finish of 5th place at the season-opening Texas 200 at Texas World Speedway and the second heat of the Trentonian 300 at Trenton International Speedway. At the Indianapolis 500, Leonard struggled to qualify after teammates Andretti and Unser qualified 6th and 8th. He eventually qualified in 29th place and finish in 18th place due to a broken hub. Leonard finished the season 15th in points.
Injury and attempted comeback
By 1974, Vel's Parnelli Jones was in trouble. Of their three cars from 1973 only Andretti in 5th place would make the top 10. They lost their Samsonite sponsorship at year's end and Firestone (Vel's Parnelli Jones tire supplier since their debut in the 1967 USAC Championship Car season) was cutting back their racing funding as well, eventually pulling out completely at the end of the year. Leonard drove the #16 Vel's Parnelli FordEagle-Offenhauser. At the season-opening heat races that made up the 1974 California 500 at Ontario Motor Speedway he finished in 4th place.
A week later in the main race, after completing 146 laps, his tire blew on the main stretch heading into turn one, causing him to drift high off the groove and crash heavily into the outside wall. He suffered a gash in his forehead and extensive injuries to his feet and legs. Since Leonard's injuries occurred before the orthopedic reconstruction methods pioneered by motorsports physician Dr. Terry Trammell, he was left severely debilitated. He finished 30th in points. A year later in 1975, Leonard attempted to make a comeback at the California 500 at Ontario Motor Speedway for Gilmore Racing in the #10 Gilmore RacingCoyote-Foyt. He ended up failing USAC's physical, ending his career.
NASCAR career
In 1969, after signing with Smokey Yunick for the Indianapolis 500, Leonard drove the #13 Smokey YunickFordTorino Talladega at the Firecracker 400 at Daytona International Speedway. Leonard crashed out after 47 laps and finish in 31st place after starting in 12th place. Due to racing with a USAC license he was unable to score points in the NASCAR Grand National Series, going unranked (a rule that no longer exists). Yunick would write in his autobiography that, "if there (was) such a thing as a natural born racer, (Leonard was) it. He liked to go fast, very fast and knew how to do it."[4]
^Yunick, Henry (2004). Best Damn Garage in Town: My Life & Adventures (1st ed.). Daytona Beach, FL: Carbon Press. p. 302. ISBN0-9724378-3-5. If there is such a thing as a natural born racer, this is it. He liked to go fast, very fast and knew how to do it.