WATT SPEED? Difference in average speed between 2 positions on a road bike. I did this test on a 4.7 km outdoor road loop with 3 corners. No braking. Temperature: 24.0 degrees Celsius Wind speed: 2.5 m/s Air density: 1.196 kg/m3 Run 1 Hands in drops Power: 201 W Speed: 33.4 km/h CdA: 0.336 m2 Run 2 Aero position Power: 200 W Speed: 36.2 km/h CdA: 0.261 m2 Run 3 Hands in drops Power: 251 W Speed: 37.2 km/h CdA: 0.314 m2 Run 4 Aero position Power: 251 W Speed: 39.5 km/h CdA: 0.258 m2 Run 5 Hands in drops Power: 301 W Speed: 39.8 km/h CdA: 0.315 m2 Run 6 Aero position Power: 300 W Speed: 42.8 km/h CdA: 0.249 m2 Run 7 Hands in drops Power: 351 W Speed: 41.9 km/h CdA: 0.319 m2 Run 8 Aero position Power: 351 W Speed: 45.3 km/h CdA: 0.249 m2