Guyot pursued an academic path before turning to motorsport professionally. He obtained a school-teaching diploma in 1984 and a DEUG in history in 1986, but in 1989, at the age of 28, he left teaching to focus on motorcycle racing. His debut season in Promosport 350, aboard a Yamaha RD 350 LC, yielded two race wins and three podium finishes. In 1990 he stepped up to Promosport 750, adding three more victories.
In 1991 Guyot established his own team, the Guyot Motorcycle Team, universally known as GMT94 — the numerals referencing Val-de-Marne, the French department where the squad is based. That same year the team entered the Superbike World Championship and raced for three seasons across 1991, 1992 and 1993, accumulating 16 World Superbike starts.
Recognising that endurance racing offered the most suitable platform for a French privateer operation, Guyot pivoted GMT94 toward the FIM Endurance World Championship, where the team became Yamaha's official factory-supported squad.
After a period of international travel in the mid-1990s, Guyot returned to competition in France, winning the French Superbike Championship in 1998. In 1999 he committed exclusively to the Endurance World Championship as a rider-manager, combining both roles.
GMT94's first major endurance result arrived in 2000 with a 24-hour race victory in Oschersleben, Germany. In 2001 Guyot won the 24 Hours Motos, a feat that as of 2017 made him the only rider-manager ever to have triumphed at that event. Further victories followed, including the 8 Hours of Brno in 2002 and, in 2004, the 8 Hours of Zhuhai alongside David Checa and William Costes. That 2004 season also brought the team's first FIM Endurance World Championship title, giving Yamaha their initial EWC crown.
Guyot formally retired from full-time riding after 2004, though he served as a substitute competitor until 2007 and made a one-off competitive return in 2011, when he and David Checa won the 5 Hours of Circuit Carole (Trophée Grégory Lemarchal).
Under Guyot's management, GMT94 accumulated three FIM Endurance World Championship titles and three victories at the 24 Hours Motos, plus two Bol d'Or wins and four French Superbike team championships. The squad served as Yamaha's official EWC representative until 2018, when it transitioned to the Supersport World Championship (WorldSSP).
The move into WorldSSP proved competitive almost immediately: in 2019, with Jules Cluzel and Corentin Perolari as riders, GMT94 finished as championship runner-up, narrowly missing the world title. In 2023 the team stepped up again, entering the full Superbike World Championship (WorldSBK) with Italian rider Lorenzo Baldassarri.
Alongside his team-management role, Guyot built a parallel career in television analysis. He has been a consultant for the Eurosport television channel, covering the Superbike World Championship, the FIM Endurance World Championship and British Superbike. Between 2012 and 2018, when Eurosport held the MotoGP broadcasting rights in France, he appeared on the channel's Dimanche Méca and Warm-up programmes. From 2019 he became a regular EWC pundit alongside Gilles della Posta, Rémy Tissier and Romain Hussonnois.
Guyot also served on the executive committee of the French Federation of Motorcycling during two separate terms (2004–2008 and 2012–2016), representing riders' interests in FIM governance between 1994 and 2004. He continues to oversee rider training at Circuit Carole and maintains involvement in road-safety initiatives through the Mutuelle des Motards.
Christophe Guyot occupies a singular position in European motorcycle sport as the architect of a long-running privateer programme that competed at the highest level across four decades. His 1991 decision to found GMT94 with his own resources shaped not only his own career but also provided a proving ground for numerous French riders. The team's three EWC titles and consistent presence in WorldSSP and WorldSBK reflect his ability to evolve a small operation built in a Val-de-Marne workshop into a fully professional international racing structure.