Patent ID: 6837822

Claim:
An improved structure of a gear cluster for a bicycle having a crankset mounted with a crankshaft provided with a planetary gear module, wherein the planetary gear module comprises a big wheel and a small wheel section and the planetary gear module drives an inner gear module mounted onto a gear plate; one lateral side of the crankshaft is provided with a driving structure including a second driving wheel and a third driving wheel engageable with the big and small wheel, and the crankshaft is provided with a regulating structure for the positioning of the driving structure and the regulating structure includes two sets of a second and a third ratchet block for the positioning or free rotating of the second and the third driving wheel, and the regulating structure is provided wit a triggering structure to act on different ratchet block, and the triggering structure makes use of a cable to provide triggering; thereby a gear shift is obtained so as to provide rapid gear shifting and to reduce the force used for gear shifting, wherein one end of the crankshaft is secured with a braking bush for securing the crankshaft having an engaging hole.