More at :http://cmgonline.com/2012/09/the-wee-ninja-grows-up-kawasaki-ninja-300/WHAT’S NEW
Kawasaki has just revised their smallest and best-selling Ninja, growing it from a 250 to a 300 and incorporating a bunch of changes to boot. As the new name suggests, the biggest mechanical change is to the engine, which has gained 47 cc of displacement purely through a longer stroke, stretching it from 41.2 to 49.0 mm.
Inside the engine are new, lighter pistons (redesigned for improved cooling), shorter connecting rods, stronger crank bearings and larger oil capacity (up to 2.4 L from 1.7). The compression ratio has also come down from 11.6:1 to 10.6, allowing regular fuel to be used (great for us cheapie CMGers).