At the age of 12 Santiago Herrero bought his first motorcycle. In 1962, he obtained his racing license, competing on a Derbi and doing his own maintenance.

He soon moved up to a Bultaco Tralla 125 and caught the eye of Luis Bejarano, the owner of Lube (a Spanish motorcycle marque) who recognized Herrero's talent. Bejarano offered him a job in the company's competition department. In 1964, Herrero finished in third place in the 125cc Spanish National Championship and in 1965, he finished in second.