172:1 Metal Gearmotor 25Dx56L mm with 48 CPR Encoder

This gearmotor consists of a low-power, 6 V brushed DC motor combined with a 171.79:1 metal spur gearbox, and it has an integrated 48 CPR quadrature encoder on the motor shaft, which provides 8245.92 counts per revolution of the gearbox’s output shaft. The gearmotor is cylindrical, with a diameter just under 25 mm, and the D-shaped output shaft is 4 mm in diameter and extends 12.5 mm from the face plate of the gearbox.

Key specifications:

These cylindrical brushed DC gearmotors are available in a wide range of gear ratios and with five different motors (two power levels of 6 V motors and three power levels of 12 V motors). The gearmotors all have the same 25 mm diameter case and 4 mm 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 48 CPR quadrature encoder on the motor shaft.

Details for item #2288

Exact gear ratio: 22×20×22×22×22×22×2412×12×10×10×10×10×10≈171.79:1

Dimensions

The diagram below shows the dimensions of the 25D mm line of gearmotors (units are mm over [inches]). This diagram is also available as a downloadable PDF (223k pdf).

Dimensions of the Pololu 25D mm metal gearmotors. Units are mm over [inches].

Warning: Do not screw too far into the mounting holes as the screws can hit the gears. We recommend screwing no further than 6 mm (0.24″) into the screw hole.

Gearmotor accessories

The face plate has two mounting holes threaded for M3 screws. You can use our custom-designed 25D mm metal gearmotor bracket (shown in the picture below) to mount the gearmotor to your project via these mounting holes and the screws that come with the bracket.

Pololu 25D mm metal gearmotor bracket pair.

Pololu 25D mm gearmotor with bracket.