EMAX MT2808

What you get

• 1.1 kg at 14.8 V

  EMAX gives the 850KV’s max thrust as 1,120 g, on a 1045 carbon fibre prop at 14.8 V and 16 A; the 660KV’s is 950 g, on a 1147 at 12.2 A.

  Source: EMAX 850KV spec sheet, EMAX 660KV spec sheet

• Over 11 g/W at light load

  At 11.1 V and 1 A both KVs made 125 g on an APC 10 × 3.8 (11.3 g/W), and the 850KV 130 g on an APC 11 × 4.7 (11.7 g/W).

  Source: EMAX 660KV spec sheet, EMAX 850KV spec sheet

• Two ways to fit props

  Ordinary props go on a screw-on adapter with an M6 thread; three-hole carbon props bolt straight to the top.

  Source: EMAX MT2808 overview, EMAX 660KV spec sheet

What to pair it with

Our reading of EMAX’s numbers, so your build matches what the motor was tested with.

ESC

On EMAX’s bench the 850KV drew up to 16 A (1045 carbon fibre prop at 14.8 V) and the 660KV up to 12.2 A (1147 at 14.8 V); a 20 A ESC covers either. (EMAX 660KV spec sheet, EMAX 850KV spec sheet)

Props

EMAX lists APC 10 to 11-inch props. It tested both KVs on an APC 10 × 3.8 and an APC 11 × 4.7 at 11.1 V, and on carbon fibre props at 14.8 V: a 1147 on the 660KV and a 1045 on the 850KV. (EMAX 660KV spec sheet, EMAX 850KV spec sheet)

Battery

3S per EMAX’s spec sheets; EMAX also tested both KVs at 14.8 V. (EMAX 660KV spec sheet, EMAX 850KV spec sheet)

Frame

Four M3 holes, 19 mm apart on one axis and 25 mm on the other; the cross mount in the box spreads that to four 3.2 mm holes on a 44 mm circle. (EMAX 660KV spec sheet, EMAX MT2808 overview)

Where to buy

• EMAX USAthe maker’s US store; 850KV, CW or CCW thread (listed as sold out)
  $15.99seen Oct 19, 2026
  Visit
• EMAX USAthe maker’s US store; 660KV, CW or CCW thread (listed as sold out)
  $15.99seen Oct 19, 2026
  Visit
• EMAXthe maker’s global store; 850KV in stock at this price, 660KV at $38.50 (sold out) or $19.25 with a plus thread
  $19.25seen Oct 19, 2026
  Visit

Plain links, not affiliate links. Prices change; the store’s page has the current one.

Full specs

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.

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, standing 2 mm above the top; props fit a screw-on adapter with an M6 thread, or bolt straight to the top. (EMAX 660KV spec sheet, EMAX 850KV spec sheet, EMAX MT2808 overview)
• Bell. Top tapped with 3 × M2.5 holes on a 15 mm circle for the prop adapter or a three-hole carbon prop, and 2 × M2.5 holes 12 mm apart. (EMAX 660KV spec sheet, EMAX 850KV spec sheet, EMAX MT2808 overview)
• Stator. The coils are wound on a stack of thin steel laminations: 28 × 8 mm (2808). (EMAX USA 850KV page, EMAX product page)
• Base. 4 × M3 holes, 19 mm apart on one axis and 25 mm on the other; the cross mount in the box takes 4 × 3.2 mm holes on a 44 mm circle. (EMAX 660KV spec sheet, EMAX 850KV spec sheet, EMAX MT2808 overview)

How fast it spins

KV is the motor’s no-load speed per volt. With nothing on the shaft, the 850KV 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.

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 × 8 mm stator, 35 mm bell, 21.3 mm height, 4 mm shaft 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

1. EMAX USA: MT Series - 2808 850kv Brushless Motor (product page, with EMAX’s MT2808 spec sheets). Retrieved Oct 19, 2026.
2. EMAX USA: MT Series - 2808 660kv Brushless Motor (product page; the same spec sheets). Retrieved Oct 19, 2026.
3. EMAX: EMAX Multicopter motor MT2808 (product page on EMAX’s global store; the same spec sheets). Retrieved Oct 19, 2026.
4. EMAX: MT2808 overview (image on EMAX’s product pages): prop fittings, drawings of the prop adapter and cross mount, and the accessory packs. Retrieved Oct 19, 2026.
5. EMAX: MT2808-660 specification (spec list, dimension drawing and bench tables at 11.1 V and 14.8 V, three props; image on EMAX’s product pages). Steps of 1 A up to the last row; EMAX’s spec list gives the last row of the 14.8 V table as the motor’s max thrust, so that row is marked as the maximum and the 11.1 V tables’ last rows are not.. Retrieved Oct 19, 2026.
6. EMAX: MT2808-850 specification (spec list, dimension drawing and bench tables at 11.1 V and 14.8 V, three props; image on EMAX’s product pages). Steps of 1 A up to the last row; EMAX’s spec list gives the last row of the 14.8 V table as the motor’s max thrust, so that row is marked as the maximum and the 11.1 V tables’ last rows are not.. Retrieved Oct 19, 2026.
7. EMAX: MT2808 CCW and plus-thread prop adapters (image on EMAX’s product pages). Retrieved Oct 19, 2026.