4.4:1 Metal Gearmotor 25Dx48L mm LP 6V
This gearmotor consists of a low-power, 6V brushed DC motor combined with a 4.4:1 metal spur gearbox. The gearmotor is cylindrical, with a diameter just under 25mm, and the D-shaped output shaft is 4mm in diameter and extends 12.5mm from the face plate of the gearbox.
Key specs at 6V: 1300RPM and 250mA (max) free-run, 8oz-in (0.6kg-cm) and 2.4A stall.
These cylindrical brushed DC gearmotors are available in a wide range of gear ratios and with five different motors (two power levels of 6V motors and three power levels of 12V motors). The gearmotors all have the same 25mm diameter case and 4mm diameter gearbox output shaft, so it is generally easy to swap one version for another if your design requirements change (though the length of the gearbox tends to increase with the gear ratio). All versions are also available with an integrated 48CPR quadrature encoder on the motor shaft. Please see the 25D metal gearmotor comparison table for detailed specifications of all our 25D metal gearmotors. This dynamically-sortable table can help you find the gearmotor that offers the best blend of speed, torque, and current-draw for your particular application.
In general, these kinds of motors can run at voltages above and below their nominal voltages; lower voltages might not be practical, and higher voltages could start negatively affecting the life of the motor.
Details for item #1581
Exact gear ratio:
Dimensions
The diagram below shows the dimensions of the 25Dmm line of gearmotors (units are mm over [inches]). This diagram is also available as a downloadable PDF (223k pdf).
| Size: | 25D x 48L mm1 |
|---|---|
| Weight: | 82 g |
| Shaft diameter: | 4 mm |
General specifications
| Gear ratio: | 4.4:1 |
|---|---|
| No-load speed @ 6V: | 1300 rpm |
| No-load current @ 6V: | 250 mA2 |
| Stall current @ 6V: | 2400 mA |
| Stall torque @ 6V: | 8 oz·in |
| Motor type: | 2.4A stall @ 6V (LP 6V) |
| Encoders?: | N |
Notes:
- 1
- Length measurement is from gearbox face plate to back of motor (it does not include the output shaft or motor terminals). See dimension diagram for details.
- 2
- Maximum.
File downloads
- Dimension diagram of Pololu 25D mm Metal Gearmotors (223k pdf)
- 3D models of 25D mm gearmotors (9MB zip)
- This file contains 3D models (in the step file format) of the 25Dmm gearmotors with and without encoders.
- Modifying the Wild Thumper to use motors with encoders (3MB pdf)
- Customer Richard Nguyen has documented his work modifying the Wild Thumper chassis to use 25D motors with encoders in place of the chassis’s included motors.
- Note: This is not an easy modification, and the chassis can be damaged if it is not done properly, so we generally recommend against it, and we can only provide very limited support for those who want to attempt it. The manufacturer did not intend for the chassis to be modified in this way, and we do not know how well such a modification will work out.
Recommended links
- MATLAB script to plot motor performance curves for Pololu brushed DC gearmotors
- This MATLAB script, written by Ali Asgher Mansoor Habiby, plots speed, power, current draw, and efficiency as they vary with torque when you input the gearmotor specifications. It also prints the resistance of the motor, and the current draw and torque at which maximum efficiency and maximum power occur.