SHORT STEM vs LONG STEM 👇 Difference in speed and power between a 90 mm and a 130 mm stem. Test protocol: 6 runs of a 4.7 km outdoor road loop. 3 corners per loop, taken without braking. Short vs long stem in ABABAB order. Weather conditions: Temperature: 24.7 - 26.4 degrees Celsius Wind speed: 3.5 - 8.3 m/s Air density: 1.116 - 1.173kg/m3 Run 1 - 90 mm stem Power: 349 W Speed: 44.7 km/h CdA: 0.262 m2 Run 2 - 130 mm stem Power: 348 W Speed: 44.7 km/h CdA: 0.261 m2 Run 3 - 90 mm stem Power: 299 W Speed: 42.3 km/h CdA: 0.261 m2 Run 4 - 130 mm stem Power: 300 W Speed: 42.8 km/h CdA: 0.254 m2 Run 5 - 90 mm stem Power: 250 W Speed: 39.0 km/h CdA: 0.274 m2 Run 6 - 130 mm stem Power: 250 W Speed: 39.8 km/h CdA: 0.257