The Chain and Sprocket Kit (T2017210) includes a 104-link chain, 43-tooth rear sprocket, and 18-tooth front sprocket. (Spacer Washers included if applicable.) This item fits Air Cooled Bonneville and Bonneville T100 Carbs, Bonneville T100 EFI, Bonneville EFI up to VIN 380776, Bonneville from VIN 380777 and up, Bonneville SE and Air Cooled Thruxton 900 Carbs.