Pullys Single V groove All pulleys have 0 spokes except 600 A series which has 4 spokes Bore diameter 3/4 inch 2 inch outside diameter, 1.75 inch pitch diameter 2-1/2 inch outside diameter, 2.25 inch pitch diameter 3 inch outside diameter, 2.75 inch pitch diameter 3-1/2 inch outside diameter, 3.25 inch pitch diameter 4 inch outside diameter, 3.75 pitch diameter 5 inch outside diameter, 4.75 inch pitch diameter