# goBILDA Yellow Jacket 139:1 Gearmotor

> goBILDA 5203-2402-0139 Yellow Jacket is a 12 V RS-555 brushed DC planetary gearmotor with 139:1 steel gearing, 43 rpm no-load output speed, 185 kg cm stall torque (9.2 A), 8 mm REX output shaft, 125.1 mm long, 486 g, and a 3.3 to 5 V magnetic quadrature encoder rated at 3895.9 PPR at the output shaft.

- Manufacturer: goBILDA
- Part number: 5203-2402-0139
- Category: Motors
- Canonical page: https://www.xirkit.io/products/gobilda-yellow-jacket-139-1-gearmotor-18ca
- Pinout: https://www.xirkit.io/products/gobilda-yellow-jacket-139-1-gearmotor-18ca/pinout
- Structured JSON: https://www.xirkit.io/products/gobilda-yellow-jacket-139-1-gearmotor-18ca/data.json
- Source: Xirkit structured parts catalog — every value traced to a cited document; unknowns are explicit.

## Key specifications

| Property | Value |
| --- | --- |
| Motor type | gearmotor |
| Rated voltage | 12 V |
| Stall torque | 18.142 N·m |
| No-load speed | 43 rpm |
| Gear ratio | 139:1 |
| Shaft diameter | 8 mm |
| Encoder | relative magnetic Hall-effect quadrature encoder, 3895.9 PPR at output shaft |
| Dimensions | 37.5 × 37.5 × 148.6 mm |

## Pinout (2 pins, 0 with electrical limits)

| Pin | Position | Kind | Chip pad | Functions | VIH | VIL | VOH | VOL | IOH | IOL | 5 V tolerant |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| MOTOR | 3.5 mm FH-MC bullet connectors | motor plus | — | motor | — | — | — | — | — | — | — |
| ENC | 4-position JST XH [FH-MC] | signal | — | enc | — | — | — | — | — | — | — |

## Where to buy

| Supplier | Price | Stock | Checked | URL |
| --- | --- | --- | --- | --- |
| www.gobilda.com | 54.99 USD | in_stock | 2026-10-01 | https://www.gobilda.com/5203-series-yellow-jacket-planetary-gear-motor-139-1-ratio-24mm-length-8mm-rex-shaft-43-rpm-3-3-5v-encoder/ |

## FAQ

**How much does the goBILDA Yellow Jacket 139:1 Gearmotor cost?**

From $54.99 at www.gobilda.com. Prices are observed unit prices before tax and shipping.

**What are the goBILDA Yellow Jacket 139:1 Gearmotor dimensions?**

37.5 × 37.5 × 148.6 mm. A STEP model is available for enclosure fit checks.

**Where does this goBILDA Yellow Jacket 139:1 Gearmotor data come from?**

Every value in this record is traced to a source — 2 documents including the board and chip datasheets — with the page and table cited per value. Unknowns are left explicit, never guessed.

## Sources

- [goBILDA Yellow Jacket 139:1 Gearmotor datasheet](https://www.gobilda.com/content/spec_sheets/5203-2402-0139_spec_sheet.pdf)
- [www.gobilda.com listing](https://www.gobilda.com/5203-series-yellow-jacket-planetary-gear-motor-139-1-ratio-24mm-length-8mm-rex-shaft-43-rpm-3-3-5v-encoder/)

## Part graph

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