2–3 inch toothpick motor
HappyModel EX1203
A 4.7 g, 12 × 3 mm motor for toothpicks: 6200KV for 2S–3S (the Larva X HD's original motor) or 5500KV for 2S–4S, with up to 183.6 g of thrust on HappyModel's 11.1 V bench (5500KV, Gemfan 3025).
- Toothpick and twig builds
- Larva X HD replacement (6200KV)
- 3-inch props (Gemfan 3025 on HappyModel's bench)
The spin is an illustration: the model turns at 1/600 of the no-load speed, and it is a generic 1203 motor drawn from HappyModel’s published sizes, not its exact design. No-load speed is KV × 11.1 V, a nominal pack for this version. HappyModel’s bench tables for it step by thrust rather than throttle, so they are in the bench data below, not on this readout.
- Weight
- 4.7 g
What you get
Larva X HD motor
The 6200KV is the original motor of HappyModel's Larva X HD.
Source: HappyModel product page
Two KVs
6200KV for 2S–3S, 5500KV for 2S–4S.
Source: HappyModel product page
Bench data for each KV
On 11.1 V with a Gemfan 3025 two-blade prop: 183.6 g at 5.8 A (5500KV) and 170.2 g at 7 A (6200KV).
Source: HappyModel product page
4.7 g
HappyModel lists 4.7 g per motor.
Source: HappyModel product page
What to pair it with
Our reading of HappyModel’s numbers, so your build matches what the motor was tested with.
- ESC
- HappyModel's bench tops out at 7 A (6200KV) and 5.8 A (5500KV) on 11.1 V with a Gemfan 3025, so an ESC rated 10 A or more per motor covers either on 3S. HappyModel publishes no 4S figures for the 5500KV. (HappyModel product page)
- Props
- HappyModel tested both KVs with a Gemfan 3025 (76 mm) two-blade prop. (HappyModel product page)
- Battery
- 2S–3S for 6200KV, 2S–4S for 5500KV. (HappyModel product page)
Full specs
| Spec | Value | Source |
|---|---|---|
| KV | 6,200 rpm/V (also 5500KV) | HappyModel product page |
| Stator | 12 × 3 mm (1203) | HappyModel product page |
| Configuration | 9N12P (9 stator slots, 12 magnet poles) | HappyModel product page |
| Battery | 2S–3S LiPo (6200KV) (5500KV: 2S–4S) | HappyModel product page |
| Weight | 4.7 g | HappyModel product page |
| Dimensions | Φ15 × 15 mm (diameter × length) | HappyModel product page |
| Shaft | 1.5 mm | HappyModel product page |
| No-load current | 0.18 A (6200KV at 12570 rpm; 5500KV: 0.14 A at 11310 rpm; HappyModel doesn't give the voltage) | HappyModel product page |
| Peak current (bench) | 7 A (where HappyModel's 6200KV bench tops out: Gemfan 3025 two-blade at 11.1 V) | HappyModel product page |
| Max power (bench) | 77.7 W (same row as the peak current) | HappyModel product page |
Bench data
Redrawn from HappyModel’s test reports. Thrust is static pull on a bench, more than you get in flight. Power is volts × amps; efficiency is thrust divided by power.
5500KV on 2S–4S, 11.1 V1 prop
| Prop | Step | Current (A) | Thrust (g) | Power (W) | Efficiency (g/W) |
|---|---|---|---|---|---|
| Gemfan 3025 (76 mm, 2-blade) | 1 | 56.3 | 11.1 | 5.072 | |
| 2 | 91.6 | 22.2 | 4.126 | ||
| 3 | 120.5 | 33.3 | 3.619 | ||
| 4 | 148.7 | 44.4 | 3.349 | ||
| 5 | 169.5 | 55.5 | 3.054 | ||
| 5.8 | 183.6 | 64.38 | 2.852 |
Source: HappyModel product page
6200KV on 2S–3S, 11.1 V1 prop
| Prop | Step | Current (A) | Thrust (g) | Power (W) | Efficiency (g/W) |
|---|---|---|---|---|---|
| Gemfan 3025 (76 mm, 2-blade) | 1 | 48.6 | 11.1 | 4.378 | |
| 2 | 78.7 | 22.2 | 3.545 | ||
| 3 | 99.7 | 33.3 | 2.994 | ||
| 4 | 125.6 | 44.4 | 2.829 | ||
| 5 | 143.5 | 55.5 | 2.586 | ||
| 6 | 160.2 | 66.6 | 2.405 | ||
| 7 | 170.2 | 77.7 | 2.19 |
Source: HappyModel product page
Inside the motor
A brushless outrunner: the coils stand still in the middle and the magnets spin around them. From the top down:
- Shaft. 1.5 mm. (HappyModel product page)
- Stator. The coils are wound on a stack of thin steel laminations: 12 × 3 mm (1203). (HappyModel product page)
How fast it spins
KV is the motor’s no-load speed per volt. With nothing on the shaft, the 6200KV version reaches about these speeds; a prop loads the motor and brings it down, typically to around 70–75% of these figures at full throttle.
| Battery | Volts | No-load rpm (KV × V) | Electrical frequency | ESC steps per second |
|---|---|---|---|---|
| 4S nominal | 14.8 | 91,760 | 9,176 Hz | 55,056 |
| 4S full | 16.8 | 104,160 | 10,416 Hz | 62,496 |
| 6S nominal | 22.2 | 137,640 | 13,764 Hz | 82,584 |
| 6S full | 25.2 | 156,240 | 15,624 Hz | 93,744 |
A 12-pole rotor has 6 pole pairs, so every turn of the shaft is 6 electrical cycles, and a six-step ESC switches the phases 36 times per turn.
About the 3D model
A generic outrunner drawn from HappyModel’s published sizes: the 12 × 3 mm stator, 15 mm bell, 1.5 mm shaft and 9 teeth and 12 magnets. Anything HappyModel doesn’t publish is typical for a motor this size, and the bell’s spoked top, the base and the inside are a generic design, not this motor’s. The colours are read off the maker’s product photos. There are no logos or markings: it is our drawing, not the maker’s.
Sources
- HappyModel: EX1203 KV5500 KV6200 2-4S brushless motor for toothpick or twig FPV drone building (product page, spec list and bench data; the tables' throttle column, in unstated units from 1439 to 2200, is left out). Retrieved Oct 19, 2026.
- HappyModel: EX1203 main product photo, used for finish. Retrieved Oct 19, 2026.
- HappyModel: EX1203 photo of the top of the bell (on the product page), used to count its windows. Retrieved Oct 19, 2026.
- HappyModel: EX1203 photo of the base (on the product page). Retrieved Oct 19, 2026.
