The number of teeth on the ratchet drive gear determines the swing arc needed for the ratchet to grab the next tooth and move the drive gear. If a drive gear has 20 teeth, the wrench must swing 18 degrees in order to grab the next tooth. With 40 teeth, the wrench must swing 9 degrees to grab the next tooth and move the drive gear.
Interchangeable Head Ratchets For Torque Wrenches.
Interchangeable Head Ratchets For Torque Wrenches.
