STANDART PULLEYS These pulleys have equally spared grooves machined into the outside diameter, to give correct meshing with the bell teeth. The pulley grooves are of a special design to give this correct meshing of the belt teeth with minimal friction. all pulleys manufactured have correct minimum meshing tolerancer built in. The pitch diameter is always larger than the outside diameter. The pulleys are normally stocked in a wide range of various diameter (no. of teeth) and standart widths.