This 143:1 gear motor is much like the GM2 gear motor but runs at nearly twice the speed. Great for robots needing speed over torque!
Solarbotics is the sole commercial outlet for the GM8, which is much like the GM2 gear motor but runs at nearly twice the speed. This 143:1 gear motor spins at 40RPM at 3V, drawing 400mA at stall generating 44.4 in*oz torque (free running at 50mA).
With a 7mm double-flat output shaft (avoid using the green double flat output - it's not meant to take rotational load), and a built-in clutch and built-in mounting screw holes, you can see why we like these motors!
These units have an overall size of 53.8mm (2.12") x 47.8mm (1.88") x 22.9mm (0.902") thick and weighs in at 31.5g or 1.13oz.
Do you need to mount something to the shaft of the motor? Although it doesn't work as well as on other motors because of the GM8's shorter output shaft, the GMW is a solid platform for a variety uses. Alternatively, you'll also find that a #2x1/4" SMS screw will provide a snug fit for your need.
(Motors are sold individually, wheels are not included)