In 2005, James Stewart entered the 450 Supercross class riding a KX250 two-stroke, following his dominance in the 125 class where he set multiple records. Despite his success in the 125 category, his rookie 450 Supercross season didn’t go as smoothly. After crashing during practice at the Phoenix race and breaking his left forearm, Stewart was forced to take two months off. Upon his return, he finished third at his home race in Orlando and won in Dallas, Seattle, and Houston. At this time, most riders were still using two-stroke bikes, giving Stewart a chance to showcase his potential.
When the series moved outdoors, most riders switched to four-stroke bikes, including Ricky Carmichael, who had joined Suzuki that year. Carmichael raced a works RM-Z450, taking advantage of Suzuki’s one-time AMA exemption to use a factory bike, while Kawasaki had not yet developed a 450 four-stroke, leaving Stewart to race his KX250 two-stroke. This put Stewart at a disadvantage against the more powerful four-strokes, a factor he later cited as a reason for his underwhelming results during the Nationals.
The 2005 outdoor season was dominated by Carmichael, who won 22 of the 24 motos, with Stewart failing to win any. The Hangtown opener showed what was to come, with Carmichael sweeping both motos. Stewart struggled with an illness in the first round, finishing sixth in the first moto and pulling out of the second. However, he showed his competitiveness at Mt. Morris, where he managed to pass Carmichael in the first moto and lead parts of the second before Carmichael regained control. Stewart finished second in both motos, showing that he could challenge Carmichael in the future.
Despite his efforts, Stewart never managed to secure a moto victory against Carmichael in the summer of 2005. Carmichael lost only two motos that season, with one of those coming at Southwick, where he crashed on his own. The other loss occurred at Unadilla, where Carmichael led the first moto until a crash in a high-speed section caused him to fall to fifth. Carmichael fought his way back up to challenge Stewart, and after 11 laps, the two engaged in an intense battle. However, disaster struck when they collided on a jump, with Stewart landing on Carmichael’s back.
The crash at Unadilla ended Stewart’s day, leaving him unconscious at the side of the track. Carmichael, visibly frustrated, continued racing and finished second behind Kevin Windham, while Stewart was unable to continue. Carmichael went on to win his sixth consecutive 450 National title, while Stewart only raced one more National before calling it quits for the season. The clash between these two legendary riders at Unadilla became one of the most memorable moments in motocross history, marking a pivotal point in both of their careers.