After more than thirty years Yamaha returns to equip on of their bikes with a three-cylinder engine and decided to do so for this aggressive-looking naked. The choice of this 850cc displacement architecture is given by the need to have a constant torque, an elastic delivery combined with 115HP of power and a low weight. The goal was to create a fun and easy naked bike with limited weight and an immediate chassis. Available to everyone without being trivial. The MT-09 was also the progenitor of a series of models, including the Tracer version with a tourism-oriented DNA, always centered around the elasticity and power of the in-line three-cylinder engine.