The inline 4 cylinder engine offers a new dimension in linear throttle action. This is achieved through the cross plane crankshaft and the 90 degrees phase positioning of its four crank panes. The rider operates the throttle producing torque. This torque is solely produced from the engine combustion. However the total engine output produced or the composite torque is nothing but the torque produced by the engine combustion and inertial torque produced by the rotation of the crankshaft. Inertial is nothing but the combustion torque. Inertial torque is generated by the rotation of the crankshaft.
Combustion torque can be operated by the operator through the throttle but inertial torque grows larger and proportional to the speed of the crankshaft rotation and thus prevents linear throttle action from being achieved. There is some out of phase reaction between these 2 torque which should not happen. The rider needs smooth torque for smooth acceleration. This is achieved by this cross plane crankshaft by differing the adjacent crankshaft by 90 degrees. By this method inertial torque fluctuation is eliminated. Thus the rider is able to achieve the linear power delivery as he rides the bike.
No commercial automobile engines have offered this inline 4 cylinder cross plane crankshaft. Yamaha has included this technology in their 2009 model and thus this technology belongs to Yamaha.
