# Tamiya 72008 4-Speed Worm Gearbox Kit **Type:** Product page · **SKU:** POLOLU-2391 · **Brand:** [Pololu](https://core-electronics.com.au/brands/pololu-australia) **Page:** https://core-electronics.com.au/tamiya-72008-4-speed-worm-gearbox-kit.html ([markdown](https://core-electronics.com.au/tamiya-72008-4-speed-worm-gearbox-kit.html.md)) ## Retired product This product is retired and no longer available for purchase. Search the catalogue for an alternative. ## Description The Tamiya 72008 4-Speed Worm Gearbox kit includes one brushed DC motor and all the gears and parts to build any of the four possible gear ratio configurations: 84:1, 216:1, 555.4:1, 1428.2:1 . The four gear ratio options give you the flexibility to choose the best speed and torque for your project. | [![](https://a.pololu-files.com/picture/0J4356.300.jpg?85d79637060bce898e4fb0f9e822bd89)](https://a.pololu-files.com/picture/0J4356.1200.jpg?85d79637060bce898e4fb0f9e822bd89) | |---| | Tamiya 72008 4-Speed Worm Gearbox Kit | The kit includes step-by-step illustrated instructions in both Japanese and English. A scanned copy of the instructions is available on the Pictures tab. The kit can be built with just a screwdriver, but the instructions recommend having [side cutters](https://core-electronics.com.au/st-1-mini-diagonal-cutter.html), [pliers](https://core-electronics.com.au/st-2-mini-long-nose-pliers.html), and a modeling knife on hand. #### Complementary products This gearbox has a 4 mm diameter, round output shaft, which works with the [wheels that are compatible with Tamiya 4 mm, round shafts](https://core-electronics.com.au/category/99/wheels-compatible-with-tamiya-4mm-round-shafts) and Pololu's [4 mm universal mounting hub](https://core-electronics.com.au/pololu-universal-aluminum-mounting-hub-for-4mm-shaft-4-40-holes-2-pack.html). Pololu's [3 mm universal mounting hub](https://core-electronics.com.au/pololu-universal-aluminum-mounting-hub-for-3mm-shaft-4-40-holes-2-pack.html) 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). The low-voltage motor in this gearbox runs on 1.5-4.5 volts and draws up to a few amps when stalled, making it compatible with Pololu's [DRV8833 motor driver carrier](https://core-electronics.com.au/drv8833-dual-motor-driver-carrier.html) if appropriate precautions are taken to avoid stalling the motor. The mounting holes on the gearbox are compatible with the [Tamiya 70098 universal plate set](https://core-electronics.com.au/tamiya-70098-universal-plate-set.html) and other [Tamiya construction series products](https://core-electronics.com.au/category/61/tamiya-products). **Features** - One type 260 motor. For motor specs, see the Mabuchi motor RE-260 (#2295) data sheet (59k pdf). - Four different gear ratios: - 84:1 - 216:1 - 555.4:1 - 1428.2:1 - Worm gear (locks the output shaft when the motor is not turning) - 4 mm round output shaft (length: 100 mm) compatible with [Tamiya wheels for 4 mm, round shafts](https://core-electronics.com.au/category/99/wheels-compatible-with-tamiya-4mm-round-shafts) and Pololu's [4 mm universal mounting hub](https://core-electronics.com.au/pololu-universal-aluminum-mounting-hub-for-4mm-shaft-4-40-holes-2-pack.html). - Assorted cranks **Note:** The Tamiya 72008 4-Speed Worm Gearbox is a *kit*; assembly is required. **People often buy this product together with:** | [![Tamiya 70110 4-Speed Crank-Axle Gearbox Kit](https://a.pololu-files.com/picture/0J265.100.jpg?d3ef208a3274f79cdeb8c9575f5db579)](https://core-electronics.com.au/tamiya-70110-4-speed-crank-axle-gearbox-kit.html) | [Tamiya 70110 4-Speed Crank-Axle Gearbox Kit](https://core-electronics.com.au/tamiya-70110-4-speed-crank-axle-gearbox-kit.html) | |---|---| | [![Tamiya 70103 Universal Gearbox Kit](https://a.pololu-files.com/picture/0J278.100.jpg?3a8291376ead64cd3aa5660f4e34213d)](https://core-electronics.com.au/tamiya-70103-universal-gearbox-kit.html) | [Tamiya 70103 Universal Gearbox Kit](https://core-electronics.com.au/tamiya-70103-universal-gearbox-kit.html) | |---|---| | [![Tamiya 72004 Worm Gearbox Kit](https://a.pololu-files.com/picture/0J268.100.jpg?c32f5dd4995f88b32f69bab54a200a83)](https://core-electronics.com.au/tamiya-72004-worm-gearbox-kit.html) | [Tamiya 72004 Worm Gearbox Kit](https://core-electronics.com.au/tamiya-72004-worm-gearbox-kit.html) | |---|---| **General specifications** | Typical operating voltage: | 3 V | |---|---| | Gear ratio options: | 84.0, 216.0, 555.4, 1428.2 :1 | | No-load motor shaft speed @ 3V: | 9400 rpm[1](https://core-electronics.com.au/#note1) | | No-load current @ 3V: | 150 mA[2](https://core-electronics.com.au/#note2) | | Stall current @ 3V: | 2700 mA | | Motor shaft stall torque @ 3V: | 0.97 oz·in[3](https://core-electronics.com.au/#note3) | **Notes:** 1A theoretical speed of the gearbox output shaft can be computed by dividing this speed by the gear ratio.2This is the no-load current of the motor when disconnected from the gears in the gearbox; the no-load current of the entire gearbox with the motor connected will be slightly higher and will vary depending on the gear ratio.3A theoretical torque of the gearbox output shaft can be computed by multiplying this torque by the gear ratio. **File downloads** - **Mabuchi motor RE-260 datasheet (see model #2295) (59k pdf)** ## Images - [Product image 1](https://core-electronics.com.au/media/catalog/product/t/a/tamiya_72008_4_speed_worm_gearbox_kit__pololu_2391__00.jpg)