If you're feeling rowdy for some reason, say exiting your favorite ribbon of asphalt, and you ask this bike to scare you, it will. Nothing, including the incredible Tuono V4, pushes you down the road like the 1,301cc reactor in the Super Duke. At low rpm, the 75-degree V-twin rumbles and pulses as it accelerates, like it's trying to jump out of the frame, and even after the tidal wave of torque has flowed past you the power just doesn't end. The KTM roars at the top of its rev band, sometimes accidentally carrying the front wheel in fourth gear. It is absolutely as addictive as it is astonishing. Yet it gets decent fuel mileage, and all the time it is completely predictable and linear, with excellent fueling and manners. It is an incredible feat of engineering and easily one of the best engines we've ever tested.