Abstract: Noise produced by a chain drive mechanism is significantly reduced by providing rubber rings on the faces of a sprocket, with the rubber rings dimensioned so that they are not contacted by the chain as it comes into engagement with the sprocket. The rubber rings absorb sprocket vibration and are as effective in reducing noise as are conventional rubber rings which are contacted by link plates of a chain to alleviate the effects of collision shocks. Since the rings need not be contacted by the chain, it is possible to reduce their thicknesses so that the sprocket can be utilized in restricted spaces.