to be "thousand rpm/volt" ... The prefix for 'kilo' is 'k', not 'K'. 'Kv' is a physical quantity , the generator constant, expressed in the unit rpm/volt, the 'K' stands for the German 'Konstant'. So, a motor has a Kv of e.g. 1500rpm/volt, or Kv=1500rpm/volt. Motor 'has 1500Kv' is wrong even