Adrian Käser first appeared in the sidecarcross world championship in 1988, on the side of Thomas Graf, participating in three GP's and earning a second place in the first race of the Czech GP as his best result.
In 1993, Käser joined Andreas Fuhrer and the new combination became a dominant force in the world championship, winning four titles in a row from 1993 to 1996,[REF] both racing for the Moto-Club Aarberg [REF].