2–3 inch toothpick motor
HappyModel EX1105
An 11 × 5 mm, 5200KV motor for 3S–4S toothpicks: 5.7 g, a 1.5 mm shaft on two bearings, and up to 207.6 g of thrust on HappyModel's 11.1 V bench with a Gemfan 3025.
- Toothpick and twig builds
- 3-inch props (Gemfan 3025 on HappyModel's bench)
- 3S–4S
The spin is an illustration: the model turns at 1/600 of the no-load speed, and it is a generic 1105 motor drawn from HappyModel’s published sizes, not its exact design. No-load speed is KV × 14.8 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
- 5.7 g
What you get
Made for toothpicks
HappyModel says it suits toothpick and twig builds.
Source: HappyModel product page
207.6 g on 3S
HappyModel's 11.1 V bench with a Gemfan 3025 two-blade prop tops out at 207.6 g and 7.9 A.
Source: HappyModel product page
Two bearings
A dual-bearing design, which HappyModel says keeps it better balanced.
Source: HappyModel product page
Plug on the leads
70 mm leads ending in a JST 1.25 mm 3-pin plug.
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 7.9 A on 11.1 V with a Gemfan 3025, so an ESC rated 10 A or more per motor covers it on 3S. HappyModel publishes no 4S figures. (HappyModel product page)
- Props
- HappyModel tested it with a Gemfan 3025 two-blade prop. (HappyModel product page)
- Battery
- 3S–4S LiPo; HappyModel's bench runs it on 11.1 V. (HappyModel product page)
- Frame
- Four M2 screws on a 9 mm circle. (HappyModel drawing)
Full specs
| Spec | Value | Source |
|---|---|---|
| KV | 5,200 rpm/V | HappyModel product page |
| Stator | 11 × 5 mm (1105) | HappyModel product page |
| Configuration | 9N12P (9 stator slots, 12 magnet poles) | HappyModel product page |
| Battery | 3S–4S LiPo | HappyModel product page |
| Weight | 5.7 g | HappyModel product page |
| Dimensions | φ14 × 17 mm (with shaft); 12 mm from the base to the top of the bell | HappyModel drawing |
| Shaft | 1.5 mm, protrudes 4 mm above the bell | HappyModel drawing |
| Mounting | 4 × M2 holes on a 9 mm circle; the base is 1.6 mm thick at the holes | HappyModel drawing |
| Bearings | 2 (dual-bearing design) | HappyModel product page |
| No-load current | 0.3 A (at 26390 rpm; HappyModel doesn't give the voltage) | HappyModel product page |
| Peak current (bench) | 7.9 A (where HappyModel's bench tops out: Gemfan 3025 two-blade at 11.1 V) | HappyModel product page |
| Max power (bench) | 87.69 W (same row as the peak current) | HappyModel product page |
| Leads | 3 leads, 70 mm including the connector, with a JST 1.25 mm 3-pin plug | 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.
5200KV on 3S–4S, 11.1 V1 prop
| Prop | Step | Current (A) | Thrust (g) | Power (W) | Efficiency (g/W) |
|---|---|---|---|---|---|
| Gemfan 3025 (2-blade) | 1 | 38.7 | 11.1 | 3.486 | |
| 2 | 75.8 | 22.2 | 3.414 | ||
| 3 | 104.9 | 33.3 | 3.15 | ||
| 4 | 132.5 | 44.4 | 2.984 | ||
| 5 | 146.5 | 55.5 | 2.64 | ||
| 6 | 175.2 | 66.6 | 2.631 | ||
| 7 | 190.1 | 77.7 | 2.447 | ||
| 7.9 | 207.6 | 87.69 | 2.367 |
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:
- Bell. The top has eight spokes and four M2 holes on a 5 mm circle round the 1.5 mm shaft. (HappyModel drawing)
- Base. 1.6 mm thick at the four M2 holes; the three leads run 70 mm to the plug. (HappyModel drawing)
How fast it spins
KV is the motor’s no-load speed per volt. With nothing on the shaft, the 5200KV 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 | 76,960 | 7,696 Hz | 46,176 |
| 4S full | 16.8 | 87,360 | 8,736 Hz | 52,416 |
| 6S nominal | 22.2 | 115,440 | 11,544 Hz | 69,264 |
| 6S full | 25.2 | 131,040 | 13,104 Hz | 78,624 |
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 11 × 5 mm stator, 14 mm bell, 12 mm height, 1.5 mm shaft, 9 mm mounting circle 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: EX1105 KV5200 brushless motors (product page, spec list and bench data; the table's throttle column, in unstated units from 1635 to 2200, is left out). Retrieved Oct 19, 2026.
- HappyModel: EX1105 dimension drawing (image on the product page). Retrieved Oct 19, 2026.
- HappyModel: EX1105 main product photo, used for finish and to count the top's spokes. Retrieved Oct 19, 2026.
- HappyModel: EX1105 side photo (on the product page), used for the colour of the base. Retrieved Oct 19, 2026.
