A variable stroke drive system for a tufting machine includes a series of drive assemblies mounted along the frame of the tufting machine. Primary drive shafts extend through the drive assemblies and are each driven by a drive motor. A series of first drive members are mounted to the primary drive shafts and are linked to associated second drive members such that the driving of the first drive members by the primary drive shafts in turn drives the second drive members. Cam arms are connected to the second drive members and to rocker arms to which push rods are mounted, the cam arms being vertically reciprocated by the rotational movement of the second drive members so as to drive the reciprocation of the push rods, and thus the needle bar(s) connected thereto along a desired stroke or reciprocating path of travel. Controlling the rate at which the primary drive shafts are driven enables control of the stroke of the needle bar(s).