Motor Sizing

Torque, speed and thermal envelope for a brushless motor under load.

Electric Motor ToolkitMode 1: efficiency vs current from Kv, Io, Rm. Mode 2: winding schemes with common slot/pole presets and kₚ, k_d, k_w.
Model
Motor constantsVoltage (V)Kv (RPM/V)Io (A, no-load)Rm (Ω @ 20°C)Weight (g)Ambient temp (°C)
Current sweepI min (A)I max (A)# of points
ESC & battery (Advanced model)In Bavaria mode, ESC and pack losses are ignored to match the original calculator. Switch to Advanced to include simple I²R models.
ESC R (Ω)Cell Ri (mΩ)# cells
Key resultsKt (Nm / A)0.0106
Km (Nm / √W)0.0671
Max system η91.0 %
I @ max η27.0 A
ModelBavaria (motor only)
At highest current (I max)Current40.0 A
Power in592.0 W
Power out534.2 W
Motor η90.2 %
System η90.2 %
Torque0.424 Nm
Copper loss40.0 W
Iron loss17.8 W
ESC loss0.0 W
Battery loss0.0 W
Total losses57.8 W
Efficiency vs currentMotor vs full system
Torque & power vs currentTorque (Nm) and output power (W)
NotesIn Bavaria model, the efficiency computation matches the classic Kv/Io/Rm-based calculator: only motor copper and iron losses are considered.
In Advanced model, ESC and battery are modeled as additional series resistances with I²R losses, giving a simple whole-system efficiency estimate.
Winding mode uses textbook definitions of pitch factor (kₚ), distribution factor (k_d), and winding factor (k_w = kₚ·k_d).
Presets are common RC motor layouts; modifying Q/P/m/span switches back to "Custom".

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Electric Motor ToolkitMode 1: efficiency vs current from Kv, Io, Rm. Mode 2: winding schemes with common slot/pole presets and kₚ, k_d, k_w.
Model
Motor constantsVoltage (V)Kv (RPM/V)Io (A, no-load)Rm (Ω @ 20°C)Weight (g)Ambient temp (°C)
Current sweepI min (A)I max (A)# of points
ESC & battery (Advanced model)In Bavaria mode, ESC and pack losses are ignored to match the original calculator. Switch to Advanced to include simple I²R models.
ESC R (Ω)Cell Ri (mΩ)# cells
Key resultsKt (Nm / A)0.0106
Km (Nm / √W)0.0671
Max system η91.0 %
I @ max η27.0 A
ModelBavaria (motor only)
At highest current (I max)Current40.0 A
Power in592.0 W
Power out534.2 W
Motor η90.2 %
System η90.2 %
Torque0.424 Nm
Copper loss40.0 W
Iron loss17.8 W
ESC loss0.0 W
Battery loss0.0 W
Total losses57.8 W
Efficiency vs currentMotor vs full system
Torque & power vs currentTorque (Nm) and output power (W)
NotesIn Bavaria model, the efficiency computation matches the classic Kv/Io/Rm-based calculator: only motor copper and iron losses are considered.
In Advanced model, ESC and battery are modeled as additional series resistances with I²R losses, giving a simple whole-system efficiency estimate.
Winding mode uses textbook definitions of pitch factor (kₚ), distribution factor (k_d), and winding factor (k_w = kₚ·k_d).
Presets are common RC motor layouts; modifying Q/P/m/span switches back to "Custom".