SAVE $400! Plus take advantage of rates from 1.9% for 24 mnths oac! Tackle any terrain. strong low-end power and torque well...Tackle any terrain. The 644 cc SINGLE OVERHEAD CAM 4-stroke engine produces strong low-end power and torque well suited to both on-road and off-road riding. Maintenance-free automatic cam chain tensioner and solid-state CD ignition with electronic advance reduce maintenance time.