When choosing a pulley, you must know the belt type it will be associated with.

There are several types of pulleys, however, the ones available at Easi-Spare are SP type. This model is slim and high.

Three types of pulleys are available at Easi-Spare, for SPZ / SPA / SPB belts. This designation refers to the belts width:

SPZ: 9.7 mm

SPA : 12.7 mm

SPB: 16.3 mm

After choosing the pulley model according to the belt type, you may choose its diameter.  We call this specification “pitch diameter”.

Then, you must choose the hub to connect this pulley on the corresponding shaft. Our article “How to choose a removable hub” will help you.

Note : during a mechanical connection with pulleys/belts, the speed remains the same when the two pulleys have the same pitch diameter. Therefore, to change speed, pulleys must have different pitch diameters. In this case, the reduction ratio R is calculated and enables the output speed to be determined (R < to 1 = speed reduces and R > to 1 = speed increases).