Aprilia or Ducati - Who builds the nastiest naked bike? On this episode of On Two Wheels, we set out to find out. Motorcyclist magazine's Ari Henning and guest tester Zack Courts saddle up to Aprilia's Tuono V4R and Ducati's Streetfighter S to see which Italian manufacturer is king of the hill. They test them on the street, at the drag strip and on the track to pick a winner.