8- to 10-inch long-range FPV motor
GEPRC EM3115
A 115 g 3115 for 8 to 10-inch long-range builds on 6S; on GEPRC’s bench at about 24 V it pulls 4,032 g at full throttle on a Hoprop MQ10X5, drawing 66.71 A.
- 8 to 10-inch long range
- 6S
- 8 to 10-inch props
The spin is an illustration: the model turns at 1/600 of the no-load speed, and it is a generic 3115 motor drawn from GEPRC’s published sizes, not its exact design. Thrust, current and power are GEPRC’s bench figures for the Hoprop MQ10X5 prop at 24.08 V, read straight across between its throttle steps. Its data starts at 20% throttle.
- Max thrust
- 4,032 g
- Hoprop MQ10X5 prop, 24.08 V
- Weight
- 115 g
- with wire
- Peak current
- 66.7 A
- full throttle
- Max power
- 1,566 W
- full throttle
from $29.99a motor at GEPRC
A set of four: $119.96
Price seen Oct 19, 2026. Plain links: we earn nothing from them.
What it pulls
GEPRC’s own bench test, one line per prop. Drag across the chart to move the throttle; the model above follows.
At 60% with the Hoprop MQ10X5: 2,439 g of thrust, 27.8 A, 667 W, 3.66 g per watt.
On your quad
24.8 : 1
Thrust to weight at full throttle: four motors pull 16,128 g with the Hoprop MQ10X5 at 24.08 V.
At 60% throttle they pull 9,756 g, 15.0 times the quad’s weight.
All-up weight is the quad ready to fly, with its battery and camera. The thrust is the maker’s static bench figure; in the air it is lower.
What you get for $29.99
4 kg on 6S
It pulled 4,032 g at full throttle on a Hoprop MQ10X5 at about 23.5 V, drawing 66.71 A, and 3,190 g on a Hoprop MQ9X4.5 at 43.2 A.
Source: GEPRC datasheet
M5 steel shaft
A 5 mm steel shaft with an M5 thread, standing 15.5 mm above the bell, with an M5 flange nut in the box.
Source: GEPRC product page, GEPRC spec image, GEPRC drawing
19 × 19 mm base
Four M3 holes on a 19 mm circle, with 310 mm 18 AWG leads.
Source: GEPRC product page, GEPRC drawing
What to pair it with
Our reading of GEPRC’s numbers, so your build matches what the motor was tested with.
- ESC
- GEPRC recommends a 60–80 A ESC and gives a 65 A peak current; its datasheet reaches 66.71 A on the 10-inch prop, where the motor ran to 97 °C. (GEPRC product page, GEPRC datasheet)
- Props
- 8 to 10-inch. GEPRC tested it on Hoprop MQ9X4.5 and MQ10X5 props; the 10-inch pulled 842 g more at full throttle and drew 23.51 A more. (GEPRC product page, GEPRC datasheet)
- Battery
- 6S (25.2 V). (GEPRC product page, GEPRC spec image)
- Frame
- Four M3 holes on a 19 × 19 mm pattern, with M3×11 screws in the box; GEPRC made it for 8 to 10-inch long-range frames. (GEPRC product page, GEPRC drawing)
Where to buy
- GEPRCthe maker’s store$29.99seen Oct 19, 2026Visit
Plain links, not affiliate links. Prices change; the store’s page has the current one.
Full specs
| Spec | Value | Source |
|---|---|---|
| KV | 900 rpm/V | GEPRC product page, GEPRC spec image |
| Stator | 31 × 15 mm (3115) (from the size in GEPRC’s name) | GEPRC product page |
| Configuration | 12N14P (12 stator slots, 14 magnet poles) | GEPRC product page, GEPRC spec image |
| Battery | 6S LiPo (25.2 V) | GEPRC product page, GEPRC spec image |
| Weight | 115 g (with wire) | GEPRC product page, GEPRC spec image |
| Dimensions | φ37.5 × 30 mm without the shaft, with 15.5 mm of shaft above the bell (the product page’s spec list gives 16 mm of shaft; the spec image and drawing give 15.5 mm) | GEPRC product page, GEPRC spec image, GEPRC drawing |
| Shaft | Φ5 mm steel shaft with an M5 thread (9.5 mm of thread), standing 15.5 mm above the bell | GEPRC product page, GEPRC spec image, GEPRC drawing |
| Mounting | 4 × M3 holes, 3.5 mm deep, on a 19 mm circle (19 × 19 mm) | GEPRC product page, GEPRC drawing |
| Magnets | N52H | GEPRC product page, GEPRC spec image |
| Bearings | NSK/NMB (as GEPRC gives it) | GEPRC product page, GEPRC spec image |
| Winding | Single-strand copper | GEPRC product page, GEPRC spec image |
| Internal resistance | 46 mΩ (GEPRC gives it as interphase resistance) | GEPRC product page, GEPRC spec image |
| Peak current | 65 A (GEPRC’s datasheet reaches 66.71 A at full throttle on the Hoprop MQ10X5) | GEPRC product page, GEPRC spec image |
| Max power | 1,620 W | GEPRC product page, GEPRC spec image |
| Leads | 18 AWG, 310 mm | GEPRC product page, GEPRC spec image |
| In the box | 4 × M3×11 round-head screws and an M5 flange nut | GEPRC product page, GEPRC spec image |
Bench data
Redrawn from GEPRC’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.
900KV on 6S2 props
| Prop | Voltage (V) | Throttle | Current (A) | Thrust (g) | Power (W) | Efficiency (g/W) |
|---|---|---|---|---|---|---|
| Hoprop MQ10X5at 24.08 Vmotor at 97 °C | 24.08 | 20% | 0.48 | 117 | 11.56 | 10.12 |
| 24.05 | 30% | 2.9 | 472 | 70.15 | 6.73 | |
| 23.91 | 40% | 6.6 | 907 | 159.04 | 5.7 | |
| 23.87 | 50% | 15.31 | 1,665 | 370.64 | 4.49 | |
| 23.8 | 60% | 27.81 | 2,439 | 667.24 | 3.66 | |
| 23.77 | 70% | 42.69 | 3,152 | 1023.36 | 3.08 | |
| 23.52 | 80% | 61.72 | 3,866 | 1464.2 | 2.64 | |
| 23.52 | 90% | 64.39 | 3,972 | 1514.4 | 2.62 | |
| 23.47 | 100% | 66.71 | 4,032 | 1565.7 | 2.57 | |
| Hoprop MQ9X4.5at 24.05 Vmotor at 71 °C | 24.05 | 20% | 0.34 | 92 | 8.2 | 11.22 |
| 24.03 | 30% | 2.76 | 386 | 66.79 | 5.78 | |
| 24.01 | 40% | 5.42 | 730 | 131.91 | 5.53 | |
| 23.99 | 50% | 9.17 | 1,071 | 221.73 | 4.83 | |
| 23.88 | 60% | 15.31 | 1,566 | 368.54 | 4.25 | |
| 23.85 | 70% | 24.47 | 2,191 | 588.59 | 3.72 | |
| 23.58 | 80% | 37.94 | 2,911 | 902.22 | 3.23 | |
| 23.58 | 90% | 40.87 | 3,062 | 963.7 | 3.18 | |
| 23.52 | 100% | 43.2 | 3,190 | 1016.1 | 3.14 |
Source: GEPRC datasheet
Inside the motor
A brushless outrunner: the coils stand still in the middle and the magnets spin around them. From the top down:
- Shaft. A high-strength 5 mm steel shaft with an M5 thread. (GEPRC product page, GEPRC drawing)
- Stator. 12N14P, with single-strand copper windings and N52H magnets. (GEPRC product page, GEPRC spec image)
- Bearings. NSK/NMB bearings, as GEPRC gives them. (GEPRC product page, GEPRC spec image)
How fast it spins
KV is the motor’s no-load speed per volt. With nothing on the shaft, the 900KV 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 | 13,320 | 1,554 Hz | 9,324 |
| 4S full | 16.8 | 15,120 | 1,764 Hz | 10,584 |
| 6S nominal | 22.2 | 19,980 | 2,331 Hz | 13,986 |
| 6S full | 25.2 | 22,680 | 2,646 Hz | 15,876 |
A 14-pole rotor has 7 pole pairs, so every turn of the shaft is 7 electrical cycles, and a six-step ESC switches the phases 42 times per turn.
About the 3D model
A generic outrunner drawn from GEPRC’s published sizes: the 31 × 15 mm stator, 37.5 mm bell, 30 mm height, 5 mm shaft, 19 mm mounting circle and 12 teeth and 14 magnets. Anything GEPRC 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
- GEPRC: EM3115 900KV Motor (product page, with the spec list). Retrieved Oct 19, 2026.
- GEPRC: EM3115 specifications (image on the product page). Retrieved Oct 19, 2026.
- GEPRC: EM3115 product drawing (image on the product page). Retrieved Oct 19, 2026.
- GEPRC: EM3115 900KV datasheet on Hoprop MQ9X4.5 and MQ10X5 props, 20–100% throttle at about 24 V (image on the product page). Each row’s voltage is as measured; the table’s voltage is its 20% row. GEPRC gives one motor temperature per prop, without saying after how long.. Retrieved Oct 19, 2026.
- GEPRC: EM3115 product photo (first gallery image). Retrieved Oct 19, 2026.
- GEPRC: EM3115 from above, showing the five-spoke top (gallery image). Retrieved Oct 19, 2026.
