The new lump increased the bore from 88mm to 90.7mm and lengthened the stroke from 65.7mm to 68.8mm over the 790 Duke. This results in a claimed 121 horsepower at 9,250 RPM and 99Nm (or 73 ft-lbs) of torque at 7,750 RPM.  

KTM added 20 percent more rotating crankshaft mass as compared to the 790 Duke, which it says increases riding stability throughout the power range. It also features new, lighter and more powerful connecting rod and new pistons, as well as a more aggressive camshaft profile. There’s also a shorter shifter and an available quickshifter option, and a larger, wider radiator for more efficient cooling.