Tamiya 72003 High-Power Gearbox Kit
 

The Tamiya 72003 high-power gearbox can be built in a gear ratio of 41.7:1 or 64.8:1,
making it well-suited for most vehicles that require a balance of speed and torque.
 

The low-voltage motors in the high-power gearbox run on 3-6 volts and draw up to a few amps,
making them perfect candidates for the Pololu low-voltage dual serial motor controller and the DRV8833 motor driver carrier.
Motor overheating can be caused by excessive stalling, even at very low voltages.
We recommend that you use stall-detection sensors, or just watch your robot, to make sure that it doesn’t stall for more than a few seconds at a time.

This gearbox has a 4 mm, round output shaft, which works with the wheels that are compatible with Tamiya 4 mm, round shafts.
Our 3 mm universal mounting hub also fits on the threaded end of the shaft,
although it is not specifically intended to work with this type of shaft (the hub’s set screw could damage the thread on the shaft).
 

For motor specs, see the
Mabuchi motor RE-260 (#2295) data sheet (59k pdf).
To compare all Tamiya gear box kits, see the Tamiya Gearbox Gear Ratio Comparison.