After having the rear tire change I have a problem with the rear brake dragging even if the rear brake is not applied. The master cylinder has been rebuilt and all lines blead out still after minimum riding the rear brake starts to drag and eventually locks. Any ideas or similar problems

 

Is there a chance that the rotor got warpped in the tire change? Also, are the axle spacers in their correct sides? Incorrect spacing will put constant pressure on the rotor to one of the pads.