A method of assembling an induction rotor includes inserting a plurality of conductor bars into a stack of disks whereby distal ends of the conductor bars project from respective axial ends of the stack, placing first and second end rings onto the respective axial ends of the stack so that the ends of the conductor bars fit into slots in the respective end rings, and compressing the slots against the conductor bars by impacting at least one of the end rings. The method may include selectively adjusting an amount of end ring material being compressed by varying heights of respective areas of a top surface of the end ring and/or selectively adjusting an amount of end ring material being compressed by varying heights of respective areas of an impacting surface.