It looks like your JB weld is under the drain plug area of cover. The picture shown has covered up the area of leak and would not be helpful to help determine source of leak. If the clutch/engine side cover is cracked it may be repairable by welding damaged area. If cover gasket is damaged or missing removal and inspection of cover would be required. If plug is leaking threads may be damaged or sealing gasket may be missing or damaged. You may require better study of your exact leak point or complaint for better advice here.
KTM Forums - Come meet sponsors, teams and the worldwide KTM forum community to discuss topics covering Super Duke, 500 EXC, RC8, KTM 690, 790, 990, 1190, 1290. KTM track racing, adventure stories, KTM 50 fix-ups and more.