Boston Gear KSD13-1 is a 60-pitch finished-bore sprocket with 13 teeth designed for 3/4-in roller chain drives. In current catalogs it’s listed as 60B13-1 and serves as the modern equivalent of the old HKSD13-1. The steel sprocket is finished with a keyway and features a 3/4 in bore, a pitch diameter of 3.1340 in, and a hub diameter of 2.3438 in, with a tooth width of 0.4590 in. It weighs 1.90 lb and is a single-strand profile with a 1/4 x 1/8 in keyway. This configuration delivers reliable power transfer for chain-drive installations requiring 13 teeth on a 60-pitch chain.
