7-inch 2S long-range FPV motor
BrotherHobby Avenger LR 2004
A long-range motor for 7-inch tri-blades on 2S: 20 × 4 mm stator, 17.5 g with leads, and 265 g of pull for 7.3 A on BrotherHobby’s 8.4 V bench.
- 7-inch 2S long range
- 2S
- 7-inch tri-blade props
The spin is an illustration: the model turns at 1/600 of the no-load speed, and it is a generic 2004 motor drawn from BrotherHobby’s published sizes, not its exact design. Thrust, current and power are BrotherHobby’s bench figures for the HQ 7 × 4 × 3 prop at 8.4 V, read straight across between its throttle steps. Its data starts at 30% throttle.
- Max thrust
- 265 g
- HQ 7 × 4 × 3 prop, 8.4 V
- Weight
- 17.5 g
- with 160 mm leads; 16.8 g with 30 mm leads, the figure the spec list gives
- Peak current
- 7.3 A
- full throttle
- Max power
- 61 W
- full throttle
from $17.99a motor at BrotherHobby
A set of four: $71.96
Price seen Oct 19, 2026. Plain links: we earn nothing from them.
What it pulls
BrotherHobby’s own bench test, one line per prop. Drag across the chart to move the throttle; the model above follows.
At 60% with the HQ 7 × 4 × 3: 109 g of thrust, 2.2 A, 18 W, 5.90 g per watt.
On your quad
1.6 : 1
Thrust to weight at full throttle: four motors pull 1,060 g with the HQ 7 × 4 × 3 at 8.4 V.
At 60% throttle they pull 436 g, 0.7 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 $17.99
4.3 g/W at full throttle
On BrotherHobby’s 8.4 V bench with an HQ 7 × 4 × 3 it pulled 265 g at full throttle for 61.32 W (4.32 g/W), and 45 g at 30% for 5.88 W (7.65 g/W).
Source: BrotherHobby drawing and load test, BrotherHobby test report
55.9 °C after two minutes
BrotherHobby measured the windings at 55.9 °C after two minutes at full throttle, at 31 °C ambient.
Source: BrotherHobby drawing and load test, BrotherHobby test report
NSK bearings, titanium shaft
Japanese NSK 8 × 3 × 4 mm bearings and a titanium-alloy shaft in a hard-anodised 7075 aluminium bell and base.
Source: BrotherHobby product page, BrotherHobby summary and features, BrotherHobby spec image
What to pair it with
Our reading of BrotherHobby’s numbers, so your build matches what the motor was tested with.
- ESC
- BrotherHobby lists a 2S 10 A ESC; the motor drew 7.3 A at full throttle on its 7-inch test prop. (BrotherHobby test report, BrotherHobby drawing and load test)
- Props
- Tested with an HQ 7 × 4 × 3 tri-blade: 265 g at full throttle on 8.4 V. (BrotherHobby drawing and load test)
- Battery
- 2S in BrotherHobby’s test and in the setup it names; the spec list gives 2S–6S. (BrotherHobby product page, BrotherHobby test report)
- Frame
- Four M2 holes on a 12 mm circle (12 × 12 mm); four M2 screws and an M5 nut come in the box. (BrotherHobby product page, BrotherHobby drawing and load test)
Where to buy
- BrotherHobbythe maker’s store; $17.99, down from $19.99$17.99seen Oct 19, 2026Visit
Plain links, not affiliate links. Prices change; the store’s page has the current one.
Full specs
| Spec | Value | Source |
|---|---|---|
| KV | 1,650 rpm/V (the only version; BrotherHobby gives it for a 7-inch tri-blade on 2S) | BrotherHobby product page |
| Stator | 20 × 4 mm (2004); 0.15 mm Nippon Steel silicon-steel laminations | BrotherHobby test report, BrotherHobby product page |
| Configuration | 12N14P (12 stator slots, 14 magnet poles) | BrotherHobby product page |
| Battery | 2S–6S LiPo (BrotherHobby names a 2S 7-inch tri-blade setup and tests it on 2S (8.4 V)) | BrotherHobby product page |
| Weight | 17.5 g (with 160 mm leads; 16.8 g with 30 mm leads, the figure the spec list gives) | BrotherHobby test report |
| Dimensions | φ24.6 × 29.9 mm (with shaft); the shaft stands 14 mm above the bell | BrotherHobby drawing and load test, BrotherHobby test report |
| Shaft | Titanium alloy, 5 mm, M5 thread (8 mm of thread) | BrotherHobby product page, BrotherHobby drawing and load test |
| Mounting | 4 × M2 holes on a 12 mm circle (12 × 12 mm) | BrotherHobby product page, BrotherHobby drawing and load test |
| Bell | 7075 aluminium bell cap and base casing, hard anodised | BrotherHobby product page, BrotherHobby summary and features |
| Magnets | N52H arc magnets | BrotherHobby spec image, BrotherHobby test report |
| Bearings | NSK (Japan), 8 × 3 × 4 mm | BrotherHobby product page, BrotherHobby spec image |
| Internal resistance | 327.4 mΩ | BrotherHobby test report |
| Idle current | 0.34 A (at 10 V) | BrotherHobby test report |
| Max current | 7.3 A (full throttle on an HQ 7 × 4 × 3 at 8.4 V) | BrotherHobby test report, BrotherHobby drawing and load test |
| Max power | 61.32 W | BrotherHobby test report, BrotherHobby drawing and load test |
| Leads | 24 AWG, 160 mm (the spec image gives 20 AWG) | BrotherHobby product page, BrotherHobby test report |
| In the box | 4 × M2 screws, 1 × M5 nut | BrotherHobby drawing and load test |
Bench data
Redrawn from BrotherHobby’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.
1650KV on 2S, 8.4 V1 prop
| Prop | Throttle | Voltage (V) | Current (A) | RPM | Thrust (g) | Power (W) | Efficiency (g/W) |
|---|---|---|---|---|---|---|---|
| HQ 7 × 4 × 3 (7-inch, three blades)motor at 55.9 °C | 30% | 8.4 | 0.7 | 3168 | 45 | 5.88 | 7.65 |
| 40% | 8.4 | 1 | 3914 | 61 | 8.4 | 7.26 | |
| 50% | 8.4 | 1.5 | 4537 | 84 | 12.6 | 6.67 | |
| 60% | 8.4 | 2.2 | 4618 | 109 | 18.48 | 5.9 | |
| 70% | 8.4 | 3.3 | 5885 | 149 | 27.72 | 5.38 | |
| 80% | 8.4 | 4.9 | 6589 | 199 | 41.16 | 4.83 | |
| 90% | 8.4 | 6.6 | 7346 | 242 | 55.44 | 4.37 | |
| 100% | 8.4 | 7.3 | 7569 | 265 | 61.32 | 4.32 |
Source: [0]
Inside the motor
A brushless outrunner: the coils stand still in the middle and the magnets spin around them. From the top down:
- Bell. 7075 aluminium bell cap, φ24.6 mm, hard anodised, with five spokes round a textured hub. (BrotherHobby product page, BrotherHobby summary and features, BrotherHobby drawing and load test)
- Shaft. Titanium alloy, 5 mm with an M5 thread, standing 14 mm above the bell. (BrotherHobby product page, BrotherHobby summary and features, BrotherHobby drawing and load test)
- Magnets. N52H arc magnets, 14 poles. (BrotherHobby spec image, BrotherHobby test report)
- Stator. 20 × 4 mm with 12 slots, in 0.15 mm Nippon Steel silicon steel. (BrotherHobby product page, BrotherHobby test report)
- Bearings. NSK, 8 × 3 × 4 mm. (BrotherHobby product page, BrotherHobby spec image)
- Base. 7075 aluminium, with four M2 holes on a 12 mm circle and 24 AWG leads 160 mm long. (BrotherHobby product page, BrotherHobby test report)
How fast it spins
KV is the motor’s no-load speed per volt. With nothing on the shaft, the 1650KV 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 | 24,420 | 2,849 Hz | 17,094 |
| 4S full | 16.8 | 27,720 | 3,234 Hz | 19,404 |
| 6S nominal | 22.2 | 36,630 | 4,274 Hz | 25,641 |
| 6S full | 25.2 | 41,580 | 4,851 Hz | 29,106 |
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 BrotherHobby’s published sizes: the 20 × 4 mm stator, 24.6 mm bell, 15.9 mm height, 5 mm shaft, 12 mm mounting circle and 12 teeth and 14 magnets. Anything BrotherHobby 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
- BrotherHobby: Avenger LR 2004 Motor (CW) (product page on BrotherHobby’s store, with its spec list, photos and Tech Specs tab). Retrieved Oct 19, 2026.
- BrotherHobby: Avenger LR 2004 full-throttle summary with the ESC, and its bell and shaft features (image on the product page). The summary gives 23.7 V; the bench table it repeats is at 8.4 V.. Retrieved Oct 19, 2026.
- BrotherHobby: Avenger LR 2004 bearings and spec list (image on the product page). It gives 20 AWG leads; the page’s text spec list and the test report give 24 AWG.. Retrieved Oct 19, 2026.
- BrotherHobby: Avenger LR 2004 dimension drawing, load test data on an HQ 7 × 4 × 3 at 8.4 V (2020 bench) and packing list (image on the product page). The copper temperature is after two minutes at full throttle.. Retrieved Oct 19, 2026.
- BrotherHobby: Avenger LR 2004-1650KV test report, 2020-07-15, with drawing, spec table and the same load table as S4 (image on the Tech Specs tab). Retrieved Oct 19, 2026.
