Idler Sprockets: Ball Bearing Idler Sprockets have sealed ball bearings with extended inner competition and setscrews for securing to the shaft.
Projection From Centerline – Due to sprockets dimensional variation among bearing manufacturers this dimension may vary slightly when different brands of bearings are used. In case you have a crucial application please demand specific dimensions.
Inner Race projection provides 2 arranged screws on long aspect to secure bearing to shaft.
“Basic Dynamic Rankings” calculated according to AFBMA standard for “Long Rating And Fatigue Life For Ball Bearings”
Accurately machined, medium carbon steel sprockets and precision floor ball bearings are assembled to supply much duty idler for the the majority of serious conditions. The bearings are pre-lubricated and sealed to retain grease and exclude dirt and moisture. They are not re-lubricatable. The extended internal race with setscrew allows fastening to a pin or shaft 
without collars or spacing devices. In addition, it provides clearance for the chain when bolting the sprocket right to a frame member or tensioning gadget. A little sprocket for close quarters and a larger one for heavier assistance is offered in each pitch. If sizes other than those listed are necessary, please inquire for quotation.