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Technical Specifications
Last Updated: 2026-10-10
Weight
Dimensions
Torque
Speed
Current
Temp
Wire
| Identity | |
| Brand |  |
| Product Number | BMS-1904 |
| Category | Hobby |
| Performance | |
| Torque |
8.4V
313.91 oz-in
22.60 kg-cm
2.2 N-m
7.4V
275.02 oz-in
19.80 kg-cm
1.9 N-m
6.0V
226.41 oz-in
16.30 kg-cm
1.6 N-m
|
| Speed |
8.4V
0.04 sec/60°
1,500.0 deg/s
250.0 RPM
7.4V
0.05 sec/60°
1,200.0 deg/s
200.0 RPM
6.0V
0.06 sec/60°
1,000.0 deg/s
166.7 RPM
|
| Physical | |
| Weight | 2.33 oz66.0 gAverage |
| Dimensions |
L 1.594 in W 0.787 in H 1.535 in L 40.5 mm W 20.0 mm H 39.0 mm |
| Drivetrain | |
| Motor Type | Coreless |
| Gears | Steel |
| Gear Spline/Teeth | 25 T |
| Rotation/Support | Dual Bearings |
| Control & Signal | |
| Modulation | Digital |
| Neutral Position | 1500 µs |
| Dead Band | 1 µs |
| Refresh Rate | 333 Hz |
| Control System | PWM |
| Electrical & Environment | |
| Operating Voltage | 4.5–8.5 V |
| Power Source | 2S Li-Po / 2S Li-Fe |
| Connectivity | |
| Connector | JR (Universal) estimate |
| Origin | |
| Country of Origin | Taiwan |
Disclaimer: Most data is sourced from the manufacturer. Some data is sourced from our loyal community and with the help of AI. We aim for accuracy but are not responsible for inaccurate information.
Class Comparison
| Weight | Average Lighter than 40% of 1902 Digital Standard servos |
Performance Analysis
| Shaft Power | 6.98–14.51 W |
| Power Density | 7.535 W/in³ More power-dense than 92% of 1759 Digital Standard servos |
| Torque Density | 3.4305 oz-in/g |
| Torque-to-Volume Ratio | 117.58 oz-in/in³ |
| Speed-to-Weight | 0.25253 (1/sec·g) |
| Speed-Torque Trade-off | 13.58 |
| Voltage Range Width | 4.0 V Wider voltage range than 92% of 1539 Digital Standard servos |
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