2–3-inch whoop motor
BetaFPV 1105
A 3S–4S whoop motor for 85 mm frames such as BetaFPV's Beta85X: about 5.2 g, with a 1.5 mm shaft for 2- to 3-inch props.
- 85 mm whoops such as the Beta85X
- 4S (5000KV) or 3S (6000KV)
- 2- to 3-inch props
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 BetaFPV’s published sizes, not its exact design. No-load speed is KV × 14.8 V, a nominal pack for this version. BetaFPV publishes no bench data for it.
- Weight
- 5.2 g
- 'about 5.2 g' a motor, about 20 g for four
Plain links: we earn nothing from them.
What you get
Two KVs for the Beta85X
5000KV for the 4S Beta85X and 6000KV for the original 3S version.
Source: BetaFPV product page
Keep the 6000KV off 4S
BetaFPV warns that the 6000KV overheats on 4S and can permanently damage the motor or the ESC.
Source: BetaFPV product page
About 5.2 g
About 5.2 g a motor, about 20 g for a set of four.
Source: BetaFPV product page
What to pair it with
Our reading of BetaFPV’s numbers, so your build matches what the motor was tested with.
- ESC
- BetaFPV pairs it with its F4 2S brushless flight controller and a BLHeli_32 16A ESC. (BetaFPV product page)
- Props
- 2- to 3-inch props: BetaFPV lists EMAX Avan 2-inch four-blades, 3020 two-blades and 3030 three-blades. (BetaFPV product page)
- Battery
- 4S for the 5000KV, 3S for the 6000KV. (BetaFPV product page)
- Frame
- Four M2 screws on a 9 mm circle; BetaFPV names its Beta85X frame. (BetaFPV product page, BetaFPV drawing)
Where to buy
- BETAFPVthe maker's store; set of 4: $39.99 (5000KV), $22.00 (6000KV); both sold out when checked$39.99seen Oct 19, 2026Visit
Plain links, not affiliate links. Prices change; the store’s page has the current one.
Full specs
| Spec | Value | Source |
|---|---|---|
| KV | 5,000 rpm/V (also 6000KV) | BetaFPV product page |
| Stator | 11 × 5 mm (1105) (from the size in BetaFPV's name) | BetaFPV product page |
| Battery | 4S (5000KV) or 3S (6000KV) LiPo (BetaFPV warns that the 6000KV overheats on 4S and can burn out the motor or ESC) | BetaFPV product page |
| Weight | 5.2 g ('about 5.2 g' a motor, about 20 g for four) | BetaFPV product page |
| Dimensions | φ14 mm; body 12.4 mm tall (BetaFPV's spec list gives a height of 14 mm, the drawing's diameter) | BetaFPV drawing |
| Shaft | 1.5 mm, protrudes 4.1 mm (the 6000KV's dimension photo shows 4 mm) | BetaFPV product page, BetaFPV drawing |
| Mounting | 4 × M2 holes on a 9 mm circle | BetaFPV product page, BetaFPV drawing |
| Bell | four M2 prop-mount holes on a 5 mm circle | BetaFPV drawing |
| Leads | Micro JST 1.25 mm 3-pin plug; 28 AWG, 55 mm (5000KV) or 30 AWG, 35 mm (6000KV) | BetaFPV product page, BetaFPV 5000KV dimension photo, BetaFPV 6000KV dimension photo |
| In the box | 4 motors | BetaFPV 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. Black anodised, with four spokes on top and four M2 prop holes on a 5 mm circle. (BetaFPV product page)
- Shaft. 1.5 mm, standing 4.1 mm above the bell. (BetaFPV product page)
- Base. Four M2 holes on a 9 mm circle. (BetaFPV product page)
- Leads. 28 AWG and 55 mm on the 5000KV, 30 AWG and 35 mm on the 6000KV, ending in a Micro JST 1.25 mm three-pin plug. (BetaFPV product page)
How fast it spins
KV is the motor’s no-load speed per volt. With nothing on the shaft, the 5000KV 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 | 74,000 | 7,400 Hz | 44,400 |
| 4S full | 16.8 | 84,000 | 8,400 Hz | 50,400 |
| 6S nominal | 22.2 | 111,000 | 11,100 Hz | 66,600 |
| 6S full | 25.2 | 126,000 | 12,600 Hz | 75,600 |
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 BetaFPV’s published sizes: the 11 × 5 mm stator, 14 mm bell, 12.4 mm height, 1.5 mm shaft and 9 mm mounting circle. Anything BetaFPV 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
- BETAFPV: 1105 Brushless Motors (product page; sold out when read). Retrieved Oct 19, 2026.
- BETAFPV: 1105 outline drawing (image on the product page). It names no KV; its 35 mm leads match the 6000KV.. Retrieved Oct 19, 2026.
- BETAFPV: 1105 5000KV dimension photo (image on the product page). Retrieved Oct 19, 2026.
- BETAFPV: 1105 6000KV dimension photo (image on the product page). Retrieved Oct 19, 2026.
- BETAFPV: 1105 5000KV main product photo, used for finish. Retrieved Oct 19, 2026.
