Measured in Watts and Kilowatts (W, kW) this is a consumer rating of typical power output set by the motor manufacturer.
Commonly, motors are rated as 350, 500, 750, 1000 Watt or 1 kW, 3 kW, 5 kW… and so on. The actual motor output varies
widely based upon usage, environment, and politics. In the technical sense the power rating of a motor or kit is at best imprecise because we are
able to affect the performance greatly by many other factors; it is more of marketing classification number and
less of a performance statistic. Instead - look at the detailed motor specifications, plug the values into calculators
and simulators to model the intended extremes, and evaluate if the results and price are affordable.
Summary:
Therefore to answer the question properly, the maximum motor output is governed by the quality of voltage and current supplied, environmental conditions, and load over Time. If we know the Km or Kt and Kv, then we can predict unloaded motor velocity which is useful when selecting rim and tire. The key factors though are stator width, rotor diameter, phase wire diameter through the axle, the number of Turns, and even the stator construction.
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