This invention describes a compact, light weight, durable, quiet in operation, economical, chain tensioning device with means for controlling chain slack between two drive sprockets, found in all terrain vehicles or the like. The assembly comprises a chain tensioning device which is spaced between the two drive sprockets. The chain tensioning device is easy to assemble, install and adjust. The device exerts a modest pre-load tension pressure, requires infrequent adjustment and is suitable for reversed loads.