7- to 9-inch long-range FPV motor
EMAX E3 2812
A 72 g motor for 7 to 9-inch long-range quads: 28 × 12 mm stator, single-strand windings, an M5 shaft on a 19 × 19 mm M3 base, and up to 3,480 g of pull per motor on EMAX’s 25 V bench (920KV, HQ 9050).
- 7 to 9-inch long range (920KV)
- 7 to 8-inch heavier builds (1150KV)
- 6S
The spin is an illustration: the model turns at 1/600 of the no-load speed, and it is a generic 2812 motor drawn from EMAX’s published sizes, not its exact design. No-load speed is KV × 22.2 V, a nominal pack for this version. EMAX’s bench tables for it step by thrust rather than throttle, so they are in the bench data below, not on this readout.
- Max thrust
- 3,480 g
- HQ 9050 prop, 25 V
- Weight
- 72 g
- without leads, both KVs
- Peak current
- 56.7 A
- full throttle
- Max power
- 1,418 W
- full throttle
from $55.42a motor at EMAX
A set of four: $221.68
Price seen Oct 19, 2026. Plain links: we earn nothing from them.
What you get for $55.42
3.5 kg on 6S
On EMAX’s 25 V bench the 920KV pulled 3,480 g at full throttle on an HQ 9050 three-blade, drawing 56.7 A; the 1150KV pulled 3,610 g on a GF8060 at 67.3 A.
Source: EMAX spec sheet and bench tables
6.6 g/W at 500 g
Making 500 g on the HQ 9050 at 25 V, the 920KV ran at 6.60 g/W, drawing 3.03 A.
Source: EMAX spec sheet and bench tables
Single-strand windings
EMAX winds the E3 with single strands, which it says lowers resistance and heat under heavy load.
Source: EMAX spec sheet and bench tables, EMAX USA product page
7075 aluminium, steel shaft
An anodised 7075 aluminium housing, a steel shaft with an M5 thread and G1-grade precision bearings.
Source: EMAX spec sheet and bench tables
What to pair it with
Our reading of EMAX’s numbers, so your build matches what the motor was tested with.
- ESC
- EMAX rates the peak current on 6S at 57 A (920KV) and 68 A (1150KV); its bench tests drew up to 67.3 A (1150KV on a GF8060). A 60 A ESC covers the 920KV and a 70 A ESC the 1150KV. (EMAX spec sheet and bench tables)
- Props
- 7 to 9-inch for the 920KV and 7 to 8-inch for the 1150KV. EMAX tested the 920KV on 9-inch GF9045 and HQ 9050 props and the 1150KV on 7 and 8-inch props (HQ 7040, GF8040, GF8060). (EMAX spec sheet and bench tables)
- Battery
- 6S: EMAX rates both KVs for 3S–6S, gives their peak figures on 6S and tested them at 25 V. (EMAX spec sheet and bench tables)
- Frame
- Four M3 holes on a 19 mm circle (19 × 19 mm); five M3×9 screws come in the box. (EMAX spec sheet and bench tables)
Where to buy
- EMAX USAthe maker’s US store; same price for both KVs (both were listed as sold out)$35.99seen Oct 19, 2026Visit
- EMAXthe maker’s global store; 920KV and 1150KV$55.42seen Oct 19, 2026Visit
Plain links, not affiliate links. Prices change; the store’s page has the current one.
Full specs
| Spec | Value | Source |
|---|---|---|
| KV | 920 rpm/V (also 1150KV) | EMAX USA product page, EMAX product page |
| Stator | 28 × 12 mm (2812) | EMAX USA product page, EMAX spec sheet and bench tables |
| Configuration | 12N14P (12 stator slots, 14 magnet poles) | EMAX spec sheet and bench tables |
| Battery | 3S–6S LiPo | EMAX spec sheet and bench tables |
| Weight | 72 g (without leads, both KVs) | EMAX spec sheet and bench tables |
| Dimensions | φ34.9 × 43.5 mm (with shaft); 36.9 mm from the bottom of the bell to the shaft tip | EMAX spec sheet and bench tables |
| Shaft | Steel, M5 thread (CW), stands 17.5 mm above the bell; 5 mm through the bearings | EMAX spec sheet and bench tables |
| Mounting | 4 × M3 holes on a 19 mm circle (19 × 19 mm) | EMAX spec sheet and bench tables |
| Bell | 7075 aluminium, anodised | EMAX spec sheet and bench tables |
| Magnets | N52SH arc magnets (from EMAX’s E3 infographic on the page) | EMAX USA product page |
| Bearings | G1-grade precision rolling bearings (the E3 infographic on EMAX USA’s page says NSK precision bearings; the spec sheet and page text say G1-grade) | EMAX spec sheet and bench tables, EMAX USA product page |
| Winding | Single-strand | EMAX spec sheet and bench tables |
| Internal resistance | 66 mΩ (1150KV 48 mΩ) | EMAX spec sheet and bench tables |
| Idle current | 1.3 A (at 10 V; 1150KV 1.6 A) | EMAX spec sheet and bench tables |
| Peak current | 57 A (on 6S; 1150KV 68 A) | EMAX spec sheet and bench tables |
| Max power | 1,425 W (on 6S; 1150KV 1700 W) | EMAX spec sheet and bench tables |
| Leads | 18 AWG silicone wire, 250 mm | EMAX spec sheet and bench tables |
| In the box | 5 × M3×9 screws; an aluminium M5 nylock nut; a washer and screw for the shaft | EMAX spec sheet and bench tables, EMAX USA product page |
Bench data
Redrawn from EMAX’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.
920KV on 6S, 25 V2 props
| Prop | Step | Current (A) | Thrust (g) | Power (W) | Efficiency (g/W) |
|---|---|---|---|---|---|
| HQ 9050 (3-blade) | 3.03 | 500 | 75.75 | 6.6 | |
| 6.2 | 853 | 155 | 5.5 | ||
| 10.7 | 1,230 | 267.5 | 4.6 | ||
| 16.9 | 1,640 | 422.5 | 3.88 | ||
| 23.5 | 2,045 | 587.5 | 3.48 | ||
| 32.2 | 2,440 | 805 | 3.03 | ||
| 41.8 | 2,832 | 1045 | 2.71 | ||
| Max | 56.7 | 3,480 | 1417.5 | 2.46 | |
| GF9045 (3-blade) | 2.62 | 415 | 65.5 | 6.34 | |
| 5.25 | 724 | 131.25 | 5.52 | ||
| 9.12 | 1,083 | 228 | 4.75 | ||
| 14.3 | 1,465 | 357.5 | 4.1 | ||
| 20.7 | 1,870 | 517.5 | 3.61 | ||
| 27.5 | 2,250 | 687.5 | 3.27 | ||
| 36.2 | 2,640 | 905 | 2.92 | ||
| Max | 48.7 | 3,250 | 1217.5 | 2.67 |
Source: EMAX spec sheet and bench tables
1150KV on 6S, 25 V3 props
| Prop | Step | Current (A) | Thrust (g) | Power (W) | Efficiency (g/W) |
|---|---|---|---|---|---|
| GF8060 (3-blade) | 3.85 | 542 | 96.25 | 5.63 | |
| 7.66 | 886 | 191.5 | 4.63 | ||
| 13.1 | 1,280 | 327.5 | 3.91 | ||
| 20.2 | 1,695 | 505 | 3.36 | ||
| 28.5 | 2,110 | 712.5 | 2.96 | ||
| 38.6 | 2,548 | 965 | 2.64 | ||
| 49.9 | 2,963 | 1247.5 | 2.38 | ||
| Max | 67.3 | 3,610 | 1682.5 | 2.15 | |
| GF8040 (3-blade) | 3.3 | 480 | 82.5 | 5.82 | |
| 6.42 | 802 | 160.5 | 5 | ||
| 11.1 | 1,170 | 277.5 | 4.22 | ||
| 17.1 | 1,572 | 427.5 | 3.68 | ||
| 24.7 | 2,010 | 617.5 | 3.26 | ||
| 33.6 | 2,460 | 840 | 2.93 | ||
| 44.2 | 2,874 | 1105 | 2.6 | ||
| Max | 58.8 | 3,540 | 1470 | 2.41 | |
| HQ 7040 (3-blade) | 2.57 | 312 | 64.25 | 4.86 | |
| 5.06 | 550 | 126.5 | 4.35 | ||
| 8.57 | 822 | 214.25 | 3.84 | ||
| 13.2 | 1,120 | 330 | 3.39 | ||
| 19.4 | 1,475 | 485 | 3.04 | ||
| 27.5 | 1,900 | 687.5 | 2.76 | ||
| 36.3 | 2,280 | 907.5 | 2.51 | ||
| Max | 46.9 | 2,710 | 1172.5 | 2.31 |
Source: EMAX spec sheet and bench tables
Inside the motor
A brushless outrunner: the coils stand still in the middle and the magnets spin around them. From the top down:
- Shaft. Steel, M5 thread (CW), stands 17.5 mm above the bell; 5 mm through the bearings. (EMAX spec sheet and bench tables)
- Bell. 7075 aluminium, anodised. (EMAX spec sheet and bench tables)
- Magnets. N52SH arc magnets (from EMAX’s E3 infographic on the page). (EMAX USA product page)
- Stator. The coils are wound on a stack of thin steel laminations: 28 × 12 mm (2812). (EMAX USA product page, EMAX spec sheet and bench tables)
- Winding. Single-strand. (EMAX spec sheet and bench tables)
- Bearings. G1-grade precision rolling bearings (the E3 infographic on EMAX USA’s page says NSK precision bearings; the spec sheet and page text say G1-grade). (EMAX spec sheet and bench tables, EMAX USA product page)
- Base. 4 × M3 holes on a 19 mm circle (19 × 19 mm). (EMAX spec sheet and bench tables)
How fast it spins
KV is the motor’s no-load speed per volt. With nothing on the shaft, the 920KV 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 | 13,616 | 1,589 Hz | 9,531 |
| 4S full | 16.8 | 15,456 | 1,803 Hz | 10,819 |
| 6S nominal | 22.2 | 20,424 | 2,383 Hz | 14,297 |
| 6S full | 25.2 | 23,184 | 2,705 Hz | 16,229 |
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 EMAX’s published sizes: the 28 × 12 mm stator, 34.9 mm bell, 26 mm height, 5 mm shaft, 19 mm mounting circle and 12 teeth and 14 magnets. Anything EMAX 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
- EMAX USA: EMAX E3 2812 Brushless Motor (product page, with its spec and per-KV electrical tables, each KV’s best full-throttle bench result and EMAX’s E3 infographics). Retrieved Oct 19, 2026.
- EMAX: E3 2812 920KV 1150KV brushless motor (product page on EMAX’s global store). Retrieved Oct 19, 2026.
- EMAX: E3-2812 motor specifications V1.0 (image on EMAX’s global product page): dimension drawing, spec table for each KV, feature list and bench tables at 25 V (920KV on two props, 1150KV on three), in steps of rising thrust ending at “Max”, full throttle. EMAX’s rpm column is left out because it has no figure at full throttle.. Retrieved Oct 19, 2026.
