Engine-related Features
1)New engine for a “superbike you can ride every day”
A newly developed 249cc, liquid-cooled,4-stroke, in-line 2-cylinder, DOHC, 4-valvefuel-injected engine that achieves the model’sconcept is adopted. With a bore x stroke spec of60.0 mm × 44.1 mm and a compression ratio of11.6:1, this engine generates its maximumpower output at 12,000r/min and maximumtorque at 10,000r/min.
A prominent feature of this newly designedengine is that it employs the latest combustionanalysis technology to ensure a sufficientvolume of air-fuel mixture intake and activelyinducing a swirl and tumble flow as it enters the combustion chamber to promote rapid combustion.
To ensure this sufficient volume of air-fuel mixture intake, a 23.5 mm diameter intake valve and a19.5 mm exhaust valve are adopted, and are set at a tight 28.5° angle to help create a compactcombustion chamber. Fresh air from the down-draft intake type throttle body is mixed with theinjection of finely atomized fuel particles (a few tens of microns in size) and effectively directed intothe combustion chamber to increase the combustion speed and minimize the occurrence of unburnedfuel at the end of the combustion process, resulting in excellent power output and torquecharacteristics. This makes for good ridability in the low- to mid-speed range, good revving feelingup through the mid- to high-speed ranges and ensures a good balance with fuel economy and otherfactors