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31/21 Brushless Motor 51g 1750Kv

KMS motors and speed controls are designed for great performance in your airplanes. The KMS engineers designed superb performance without the high price tag. With a full line of products, KMS has products for you.

High Performance Brushless Motor without the High Performance Price

Perfect replacement for 370, 380, 400, and 480 geared brushed motors. Requires brushless speed control. We recommend the KMS 18A.

Specifications:

  • Size: 31 x 28 (mm)
  • Weight: 51g/1.8oz.
  • Max Efficiency: 80%
  • Battery: 2-3 Cell Lipo
  • Recommended Prop: 8 x 4, 9 x 4
  • Current:1.3-13A
  • Voltage: 7.4 - 11.1
  • Shaft Dia: 3mm
  • Prop Adaptor: 5mm
  • Connectors: 2mm Gold Xtra Plugs

    •

    108025

    More Information

    Informal testing was done on this motor using the Impulse 1320Mah lipo battery, the KMS 18A ESC, and APC and GWS Props. You can expect similar results.
    Battery Prop Volts Amps Watts RPM
    11.1v lipo 10x3.8 10.72 9.69 104.5 6200
    11.1v lipo 10.4.7 10.62 11.25 115.6 5700
    11.1v lipo 9x4.7 11.6 7.94 86.9 7200
    11.1v lipo 9x6 10.63 10.77 112.6 5800
    7.4v lipo 9x6 7.46 6.44 46.9 4600
    7.4v lipo 10x3.8 7.57 5.87 44 4900
    7.4v lipo 10x4.7 7.46 6.67 49.6 4500
    7.4v lipo 9x4.7 7.64 4.72 34.3 5400