The frame is the main part of the motorcycle that determines how the machine rides and handles during straight-line running, in high-stress conditions such as acceleration and in the curves. If the frame is too stiff it makes riding uncomfortable and it lacks the flexibility to absorb shocks. So a good "rigidity balance" is necessary, and that is what Yamaha focuses on in frame design. In specific terms, the rigidity is tested by fixing the head pipe in a vice and analyzing the results of applying force at the pivot point where the rear arm is attached. Force is applied longitudinally, laterally and torsionally (twisting) and the rigidity balance is adjusted based on the results. The Deltabox frame has a structure that makes it easy to get sufficient strength and a good rigidity balance. It is design fed back from world class racing.