Different belts have different dimensions. They also use different materials; for instance, the cord inside an A section V-belt is smaller than the cord inside a B section V-belt. While this larger cord gives a B section belt more power capacity, it also means that your sheaves have to be above a larger minimum size than an A section belt’s sheaves. This applies to all of our belt lines. The smaller section belts can use smaller diameter sheaves and sprockets. The same concept applies to backside idlers as well. Going below these minimums on either the inside, or the backside of the belts can have a significant affect on belt life. To find out what minimum diameter sheave, sprocket, or idler your belt needs, check out our Belt Preventive Maintenance Manual available for free at www.gates.com/catalogs Click on the hyperlink for Power Transmission Catalog Collection to get to the page where you can download it.