3SR Simplex Sprockets 06B-1
Pilot bore sprockets are usually manufactured from C45 Steel and the large sprockets maybe supplied in G22 Cast Iron. These pilot bore sprockets allow the end user to machine the bore to suit their own application. The bore would then require a key way to be broached and threaded holes made through the boss to secure the sprocket to the shaft. The nominal pilot bore is purely to permit tooling to be used to machine the bore to size and should not be taken as a shaft sized finish.