Abstract: An improved system in an endless track unit of an all-terrain vehicle. A track is driven with a drive wheel that has sprocket disks drivingly engaging the track with more than two teeth from those disks drivingly engaging the track at any given time. The track is trained around the drive wheel and a plurality of undriven guide wheels. A damper wheel may sit downstream of the drive wheel between the drive wheel and the first guide wheel and supports the underside of the track. A preferred embodiment has a sprocket disk with thirteen cogs that have a generally tear-shaped cross section forming teeth of the sprocket, more than two of which drivingly engage a stretch-resistant track at any given time. The track a continuous belt formed of molded rubber with stretch-resistant chords imbedded therein.