8- to 9-inch FPV motor
RCinPower EX2812 Plus
A 76 g 2812 in 900KV that RCinPower tested on 8- and 9-inch three-blades at 24 V, pulling 2,586–3,508 g per motor at full throttle.
- 8- and 9-inch quads
- 4S–6S
- 8- and 9-inch three-blade props
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 RCinPower’s published sizes, not its exact design. Thrust, current and power are RCinPower’s bench figures for the Gemfan 9045, 3-blade prop at 24 V, read straight across between its throttle steps. Its data starts at 25% throttle.
- Max thrust
- 3,508 g
- Gemfan 9045, 3-blade prop, 24 V
- Weight
- 76 g
- with 3 cm leads
- Peak current
- 52.8 A
- full throttle
- Max power
- 1,267 W
- full throttle
from $23.99a motor at FPVStoreRC
A set of four: $95.96
Price seen Oct 19, 2026. Plain links: we earn nothing from them.
What it pulls
RCinPower’s own bench test, one line per prop. Drag across the chart to move the throttle; the model above follows.
At 60% with the Gemfan 9045, 3-blade: 1,711 g of thrust, 19.0 A, 455 W, 4.05 g per watt.
On your quad
21.6 : 1
Thrust to weight at full throttle: four motors pull 14,032 g with the Gemfan 9045, 3-blade at 24 V.
At 60% throttle they pull 6,843 g, 10.5 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 $23.99
Bench data from 25% to full throttle
Two 8-inch and two 9-inch three-blades at 24 V, in four throttle steps, with the temperature after 5 s at full throttle.
Source: RCinPower spec sheet
Most efficient at low current
RCinPower gives over 85% efficiency at 4–9 A.
Source: RCinPower spec sheet
76 g
76 g with 3 cm leads, on a 28 × 12 mm stator with a 4 mm hollow shaft.
Source: RCinPower spec sheet
What to pair it with
Our reading of RCinPower’s numbers, so your build matches what the motor was tested with.
- ESC
- At full throttle on 6S it drew 44–45 A on the 8-inch props and 51.4–52.8 A on the 9-inch props, running at 69–80 °C. RCinPower rates it at 52.8 A; an ESC rated for at least 55 A per motor covers every prop tested. (RCinPower spec sheet)
- Props
- The Gemfan props pulled more than the HQProps of the same diameter: 3,508 g on the Gemfan 9045 and 2,923 g on the Gemfan 8040, against 3,097 g and 2,586 g on the HQProp 9040 and 8045. The Gemfan 9045 was the most efficient at full throttle. (RCinPower spec sheet)
- Battery
- 4S–6S; RCinPower tested it on 6S. (RCinPower spec sheet)
- Frame
- Four M3 screws, opposite holes 19 mm apart. (RCinPower spec sheet)
Where to buy
- FPVStoreRC900KV$23.99seen 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 | RCinPower spec sheet |
| Stator | 28 × 12 mm (2812) | RCinPower spec sheet |
| Configuration | 12N14P (12 stator slots, 14 magnet poles) | RCinPower spec sheet |
| Battery | 4S–6S LiPo | RCinPower spec sheet |
| Weight | 76 g (with 3 cm leads) | RCinPower spec sheet |
| Dimensions | φ33.3 × 26.1 mm (without the shaft) | RCinPower spec sheet |
| Shaft | 4 mm hollow; 5 mm across the thread, which stands 14.5 mm above the bell | RCinPower spec sheet |
| Mounting | 4 × M3 holes, opposite holes 19 mm apart (19 × 19) | RCinPower spec sheet |
| Internal resistance | 85 mΩ | RCinPower spec sheet |
| No-load current | 1.2 A (at 10 V) | RCinPower spec sheet |
| Max current | 52.8 A (RCinPower labels it 5S; it is the same as its highest bench reading (Gemfan 9045 three-blade at 24 V)) | RCinPower spec sheet |
| Max continuous power | 1,267 W (RCinPower labels it 5S; its Gemfan 9045 reading at 24 V is 1267.2 W) | RCinPower spec sheet |
Bench data
Redrawn from RCinPower’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 4S–6S, 24 V4 props
| Prop | Throttle | Current (A) | Thrust (g) | Power (W) | Efficiency (g/W) |
|---|---|---|---|---|---|
| Gemfan 9045, 3-blade (GF9045*3)motor at 80 °C | 25% | 3.5 | 609 | 84 | 7.25 |
| 50% | 11.4 | 1,240 | 273.6 | 4.532 | |
| 75% | 30.3 | 2,417 | 727.2 | 3.324 | |
| 100% | 52.8 | 3,508 | 1267.2 | 2.768 | |
| HQProp 9040, 3-blade (HQ9040*3)motor at 79 °C | 25% | 3.6 | 602 | 86.4 | 6.968 |
| 50% | 12.3 | 1,228 | 295.2 | 4.16 | |
| 75% | 30.3 | 2,268 | 727.2 | 3.119 | |
| 100% | 51.4 | 3,097 | 1233.6 | 2.511 | |
| Gemfan 8040, 3-blade (GF8040*3)motor at 70 °C | 25% | 3 | 508 | 72 | 7.056 |
| 50% | 9.9 | 1,033 | 237.6 | 4.348 | |
| 75% | 25.9 | 2,014 | 621.6 | 3.24 | |
| 100% | 45 | 2,923 | 1080 | 2.706 | |
| HQProp 8045, 3-blade (HQ8045*3)motor at 69 °C | 25% | 3 | 502 | 72 | 6.972 |
| 50% | 10.5 | 1,024 | 252 | 4.063 | |
| 75% | 25.9 | 1,890 | 621.6 | 3.041 | |
| 100% | 44 | 2,586 | 1056 | 2.449 |
Source: RCinPower spec sheet
Inside the motor
A brushless outrunner: the coils stand still in the middle and the magnets spin around them. From the top down:
- Shaft. 4 mm hollow; 5 mm across the thread, which stands 14.5 mm above the bell. (RCinPower spec sheet)
- Stator. The coils are wound on a stack of thin steel laminations: 28 × 12 mm (2812). (RCinPower spec sheet)
- Base. 4 × M3 holes, opposite holes 19 mm apart (19 × 19). (RCinPower spec sheet)
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 RCinPower’s published sizes: the 28 × 12 mm stator, 33.3 mm bell, 26.1 mm height, 5 mm shaft, 19 mm mounting circle and 12 teeth and 14 magnets. Anything RCinPower 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
- RCinPower: EX2812 Plus (product page; its content is three images with renders, the spec table, dimension drawing and bench data). Retrieved Oct 19, 2026.
- RCinPower: EX2812 Plus renders (first image on the product page), used for finish. Retrieved Oct 19, 2026.
- RCinPower: EX2812 Plus renders (second image on the product page, with the base). Retrieved Oct 19, 2026.
- RCinPower: EX2812 Plus spec sheet (third image on the product page: the EX-2812 900KV spec table, drawing and bench tables at 24 V from 25% to 100% throttle, with temperatures after 5 s at full throttle). Retrieved Oct 19, 2026.
