The Kawasaki Ninja EX300cc is based on the Ninja 250R, a lightweight and inexpensive sport bike in production for over three decades.Like the Ninja 250R, it has a full fairing, but a wider rear tire, 140/70, than the instead of 130/70 on the 250R.The Ninja 300 also has 5 spoke wheels, neutral finder, and optional (ABS).By comparison with the 250R, the Ninja 300 also has a slightly smaller fuel tank, taller gearing, and a back-torque-limiting slipper clutch with an assist mechanism that decreases clutch lever effort. Despite being a sport bike, it has comfortable ergonomics (such as mid-position foot controls and an upright seat) which promote commuting.
The Kawasaki Ninja EX300cc has a 296 cc (18.1 cu in. ) straight-twin engine Dynamometer tests showed that the Ninja 300 produces more power with 39.95 hp (29.79 kW) compared with the 250’s 25.48 hp (19.00 kW), and higher torque across the rev range at 18 to 13.57 lb⋅ft (24.40 to 18.40 N⋅m).
Its top speed has been recorded at 180 km/h (112 mph) and acceleration at 5.6 seconds from 0 to 97 km/h (0 to 60 mph), and around 14.5 seconds at 141.14 to 145.77 km/h (87.7 to 90.58 mph) in the quarter mile.
The Ninja 300’s fuel economy was measured at around 70 mpg‑US (3.4 L/100 km; 84 mpg‑imp), while other sources reported it at 54.1 mpg‑US (4.35 L/100 km; 65.0 mpg‑imp), though regardless of the methodology, the 300 showed improved gas mileage over the Ninja 250R.