The CBR600RR’s high-powered 600cc inline-4 engine has proved itself to be a force to be reckoned with both on and off the circuit. Featuring a highly compact configuration that helps realize optimal mass centralization and a longer swingarm (which combine to play a significant role in the CBR’s exceptional handling) this engine delivers a broadly responsive range of power and blistering acceleration to leap out of corners and strafe the straights of the racing circuit.
Fundamentally unchanged for 2005, its innovative Dual Sequential Programmed Fuel Injection system (PGM-DSFI) continues to utilize two full sets of injectors to provide optimum fuel feed for top performance throughout the engine’s wide rev range. With one set located at the mouths of the engine’s intake ports, the other is positioned high above the air intake velocity stacks to deliver an extra shot of finely atomized fuel spray for optimized performance at high-revving engine speeds. Moreover, adoption of a new type of injectors attained improvements in response along with a small but significant 64g reduction in weight.
For its second generation, the CBR600RR’s engine received detailed modifications designed to realize smoother and stronger, more torque-filled midrange performance, for a noticeable improvement in roll-on acceleration and overtaking speed. This was partially achieved by narrowing the middle section of the intake ports to greatly accentuate the venturi effect. This slight constriction effectively increases intake speed and air/fuel mixture volume to the combustion chambers for faster and more complete filling of the cylinders in the short interval that the intake valves remain open. More air/fuel mixture in translates directly to stronger torque out, for quicker surges up to speed.
Combined with the chassis’ significant 6kg weight loss, this extra boost in midrange power output translates into a major increase in the CBR’s power-to-weight ratio. The end result: quicker acceleration and faster lunges out of the corners in the heat of competition, and more satisfying response every time one twists the throttle.