New KTM 390 Duke (Slipper Clutch) | Review | PowerDrift The Duke 390 has managed to impress everyone with its performance per rupee quotient. In its new, 2016 avatar, the hot favorite Duke has got some cosmetic and functional upgrades, the biggest one being the slipper clutch. And this comes at no extra price! We find out how the new Duke 390 fares.