A double-linkage safety brake system, at least comprising: a brake handle (2). An integral driving arm (20) is provided, and a supporting shaft (200) is provided between the driving arm (20) and a base (3); one end of a first connecting rod (21) is axially disposed at a first pivot hole (201) close to the supporting shaft (200), and the other end of the first connecting rod (21) is linked to a rear wheel brake line (40) to drive a rear wheel brake to operate; one end of a second connecting rod (22) is provided at a second pivot long hole (202) far away from the supporting shaft (200), and the other end of the second connecting rod (22) is linked to a front wheel brake line (41) so as to drive a front wheel brake to operate; when the brake handle (2) is pressed against a first motion, the first connecting rod (21) may be driven directly and in real time by the first pivot shaft hole (201) close to the supporting shaft (200) to be displaced so as to output a first brake force to the rear wheel brake (50); when the first connecting rod (21) reaches a time difference of a set displacement distance, the second connecting rod (22) will be joined and simultaneously driven, and a second brake force is output to the front wheel brake; in this way, a one-time brake operation of a driver may generate a first brake force and a second brake force having a time difference starting from the moment of being generated by means of the first connecting rod (21) and the second connecting rod (22), so as to make the rear wheel brake and the front wheel brake generate brake actions having a time difference; and then, when the driver increases brake force, the second brake force generated by the second connecting rod (22) will be greater than the first brake force generated by the first connecting rod (21), thereby increasing the brake force of the front wheel brake (51). The time difference starts the braking process at the rear wheel then brings in the front wheel, preventing unsafe bicycle behaviour exhibited if the front brake is activated first.
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