Harley-Davidson Sportster S vs Kawasaki Z900

The Harley-Davidson Sportster S (2025) and the Kawasaki Z900 (2025) are compared with the same Moto Kıyas physics model under identical conditions: flat dry asphalt, no wind, a 75 kg rider and no passenger. The Harley-Davidson Sportster S is a cruiser with 1,252 cc, 120.7 hp and 228 kg; the Kawasaki Z900 is a naked bike with 948 cc, 122.0 hp and 213 kg. Power-to-weight with the rider: 398.3 hp/ton versus 423.7 hp/ton. On this measure the Kawasaki Z900 is 6% ahead.

In the simulation the Harley-Davidson Sportster S covers 0-100 km/h (speedometer) in 2.97 s and the Kawasaki Z900 in 3.13 s; the Harley-Davidson Sportster S is quicker by 0.16 s. In the 100-0 km/h brake test, braking distance without the 0.3 s reaction time is 44.7 m for the Harley-Davidson Sportster S (with ABS) and 43.7 m for the Kawasaki Z900 (with ABS). The Kawasaki Z900 stops 1.0 m shorter. Calculated top speed: 194 km/h (manufacturer claim) versus 234 km/h (manufacturer claim).

All values are an estimated simulation, not road-test measurements. Technical data comes from the sources listed below; the model uses model-specific parameters calibrated against published road tests for both. Open the interactive app (currently in Turkish) to watch the run side by side and change the load.