This bike is almost a twin to her sister ST 2.9 which differs externally by the larger size of the crown and the small size of the cylinder. In addition to incorporating all the new series already presented in the ST, the small 125 cm3 engine has undergone some minor adjustments that increase efficiency and provides unmatched acceleration capability. This achieves the speed of 16,000 revolutions / minute while preserving the qualities of the engine at low speed, essential for trial.

For the chassis, the ST 1.25 is equipped with the best equipment in the ST range, including Formula frain kit developed in close collaboration with the technical department Sherco, the adjustable foot rests, new suspension settings and adjustments in the driving position.