Align BL Series BL500L Kv (rpm/V) 1650 Max Power (W) 1800W Max Amp (15sec) 85A Max Efficiency 85% Io (No load A) Rm (Resistance) Shaft Diameter 5mm Gearbox N/A Motor Diameter 43.5mm Motor Length 65mm Motor Weight 300g Built in Fan Yes Max Rpm 40,000 Poles 6 Case Finned ESC Timing 5-18 deg ESC Switching Freq. 16-22KHz