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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 1.5-4.5 volts and draw up to a few amps, making them perfect candidates for 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 diameter, 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 smaller 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.

Specifications
Typical operating voltage: 3 V
Gear ratio options: 41.7, 64.8 :1
Free-run motor shaft speed @ 3V: 9400 rpm1
Free-run current @ 3V: 150 mA2
Stall current @ 3V: 2700 mA
Motor shaft stall torque @ 3V: 0.97 oz·in^3