A drive gear has a gear hub with a ledge. A plurality of gear teeth are formed at an outer periphery of the ledge, and centered about a central axis. A mount structure extends axially away from the ledge. A first distance is defined between axial ends of the gear teeth. A second distance is defined between ends of the gear hub. A ratio of the first distance to the second distance is between 0.52 and 0.54. An oil pump, a rotating portion for an electrical generator, and a generator are also disclosed. An oil pump, a rotating portion for an electrical generator, and a generator are also disclosed.