With the soon-to-be-announced KRX H2 SXS on the horizon, I thought it would be good to dive into the current H2 engine and see what it's all about. The KRX H2 engine will be built to make more power than the Ninja H2 but less than the Ninja H2R engine. See the full Kawasaki Ninja H2 engine specs below.
The Kawasaki Ninja H2 is powered by a supercharged 998cc inline 4-cylinder engine, renowned for its exceptional performance in the hypersport motorcycle category. Below are the detailed specifications of the Kawasaki Ninja H2 engine, based on the most recent models (2024-2025) and consistent across variants like the H2, H2 Carbon, and H2 SX, with notes on differences where applicable:
Engine Specifications
- Type: Liquid-cooled, 4-stroke, DOHC (Double Overhead Camshaft), 16-valve, inline 4-cylinder
- Displacement: 998 cc (60.9 cubic inches)
- Supercharger: Centrifugal, scroll-type, designed in-house by Kawasaki Heavy Industries (KHI)
- Impeller: 69mm, 12-blade, 3D-machined from forged aluminum, spins at up to 130,000 RPM (9.2x crankshaft speed)
- Boost Pressure: Up to 2.4x atmospheric pressure (approximately 2.4 bar)
- Efficiency: High-efficiency design minimizes heat gain, eliminating the need for a bulky intercooler
- Bore x Stroke: 76.0 mm x 55.0 mm
- Compression Ratio: 8.5:1 (optimized for high-performance supercharged operation)
- Power Output:
- Ninja H2/H2 Carbon (Street-Legal): Approximately 227.83 horsepower (166.4 kW) at 11,500 RPM (with ram-air, up to 231 hp)
- Ninja H2R (Track-Only): Over 310 horsepower (230 kW), up to 326 hp with ram-air
- Ninja H2 SX/SX SE (Sport-Touring): 197.2 horsepower (147 kW) at 11,000 RPM (detuned for low to mid-range power and efficiency)
- Torque:
- Ninja H2/H2 Carbon: 141.7 Nm (104.9 ft-lbs) at 11,000 RPM
- Ninja H2 SX/SX SE: 137.3 Nm (101.3 ft-lbs) at 8,500 RPM
- Fuel System: Electronic fuel injection with dual injectors per cylinder
- Top injectors spray fuel onto stainless steel nets over intake funnels for improved fuel-air mixture and cooling
- Intake System:
- Ram Air duct (H2 and H2 SX) optimizes airflow to the supercharger
- Revised intake chamber and funnel lengths in H2 SX for better low to mid-range performance
- Exhaust System:
- Oval-shaped header pipe entrances match dual exhaust ports per cylinder
- Hydroformed header and collector pipes for durability and flow efficiency
- Exhaust valves made of Inconel (heat-resistant nickel alloy) and stainless steel to handle high-temperature exhaust gases
- Transmission: 6-speed manual with dog-ring gearbox for smooth, quick shifts
- Clutch: Hydraulic Assist & Slipper Clutch with assist and slipper cams to reduce lever effort and prevent rear wheel hop during downshifts
- Quickshifter: Bidirectional (up/down) Kawasaki Quick Shifter (KQS) for clutchless shifts
- Engine Management:
- Fully electronic throttle actuation system for precise control of fuel and air
- Advanced ECU with inputs from throttle position sensor, traction control, launch control, and engine brake control
- Economical Riding Indicator displays “ECO” mark on the LCD for fuel-efficient riding
- Lubrication: Transmission oil jets (first in a Kawasaki motorcycle) enhance durability
- Cooling: Liquid-cooled with high-efficiency radiator; winglets on fairings aid cooling airflow
- Design Collaboration: The supercharger and engine were developed with input from Kawasaki’s Gas Turbine & Machinery Company, Aerospace Company, and Corporate Technology Division, ensuring a compact, high-output design tailored for motorcycle use.
- H2 vs. H2R: The H2R’s engine shares the same 998cc displacement but uses different internals (e.g., camshafts, ECU mapping, and exhaust) for significantly higher power, making it non-interchangeable with the H2. The H2R is hand-built in a special facility and tuned for track use, producing up to 50% more power.
- H2 SX Differences: The H2 SX engine is a “second-generation” supercharged design, with a revised supercharger impeller and intake system for better fuel economy and low to mid-range power, achieving similar MPG to the Kawasaki Versys 1000.
- Performance Context: The centrifugal supercharger provides linear power delivery compared to turbocharged bikes of the 1980s, avoiding turbo lag. Its high-RPM performance (1,200 to 14,000 RPM) supports rapid acceleration and precise rider control.
- Maintenance: The H2R requires service inspections every 15 hours of operation above 8,000 RPM, reflecting its extreme performance demands.