The high-speed gearbox can be assembled in 11.6:1 and 18:1 gear ratios. The high-efficiency gearbox is therefore suited for very fast vehicles or other fast mechanisms that do not require high torque.

The motor is rated for 3 volts but will typically work fine up to 6 volts. When using this product with the dual serial motor controller (or any motor driver based on an H-bridge), keep in mind that up to a few volts (depending on the load) are lost on the transistors of the H-bridge, so that a 4.5 volt battery delivers about 3 volts to the motors, giving them a reasonable amount of power. 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.

The 4mm, round output shaft is compatible only with Tamiya's sports and narrow tyre set. See 'Which Wheel' tab for suitable wheels type 4P for a tight fit.

(Note: This gearbox uses the RE-260RA-2295 motor variant)