EMAX RS1306 V2

What it pulls

EMAX’s own bench test, one line per prop. Drag across the chart to move the throttle; the model above follows.

What you get

• 500 g on 4S

  At 14.8 V the 4000KV pulled 500 g at full throttle on EMAX’s AVAN 3024, drawing 19.5 A; the 2700KV pulled 336 g on the same prop at 16.8 V and 8.2 A.

  Source: EMAX 4000KV test report (14.8 V), EMAX 2700KV test report (16.8 V)

• T-mount and open base

  EMAX redesigned the RS1306 around a T-mount prop fitting (M2 holes 5 mm apart) and an open-bottomed base, to take weight off the ends of the arms.

  Source: EMAX USA product page, EMAX product page

• 4.5 g/W at half throttle

  At 12.6 V on the AVAN 3024 the 2700KV made 62 g at 50% throttle, at 4.47 g/W.

  Source: EMAX 2700KV test report (12.6 V)

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 4000KV drew up to 19.5 A at 14.8 V and the 2700KV up to 8.3 A at 16.8 V; a 20 A ESC covers either. (EMAX 4000KV test report (14.8 V), EMAX 2700KV test report (16.8 V))

Props

3-inch props, per EMAX; it tested both KVs on its AVAN 3024 and a Kingkong 3045. (EMAX USA product page, EMAX 4000KV test report (12.6 V), EMAX 2700KV test report (12.6 V))

Battery

3S–4S. EMAX gives the max thrust on 4S and tested the 4000KV at 12.6 and 14.8 V and the 2700KV at 12.6 and 16.8 V. (EMAX USA product page, EMAX 4000KV test report (12.6 V), EMAX 4000KV test report (14.8 V), EMAX 2700KV test report (12.6 V), EMAX 2700KV test report (16.8 V))

Frame

Four M2 holes, 12 × 12 mm. (EMAX USA product page)

Where to buy

• EMAX USAthe maker’s US store; same price for both KVs (both listed as sold out)
  $10.99seen Oct 19, 2026
  Visit
• EMAXthe maker’s global store; 2700KV and 4000KV (both listed as sold out)
  $16.92seen 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. 1.5 mm. (EMAX USA product page, EMAX product page)
• Bell. T-mount prop fitting: M2 holes 5 mm apart. (EMAX USA product page, EMAX product page)
• Stator. The coils are wound on a stack of thin steel laminations: 13 × 6 mm (1306). (EMAX USA product page, EMAX product page)
• Bearings. 2 × 5 × 2.5 mm. (EMAX USA product page, EMAX product page)
• Base. 4 × M2 holes, 12 × 12 mm. (EMAX USA product page, EMAX product page)

How fast it spins

KV is the motor’s no-load speed per volt. With nothing on the shaft, the 4000KV 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 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 EMAX’s published sizes: the 13 × 6 mm stator, 16.8 mm bell, 1.5 mm shaft, 12 mm mounting circle and 9 teeth and 12 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: RS1306 Version 2 - Brushless Racing Motor (product page, with the spec list and EMAX’s test reports). Retrieved Oct 19, 2026.
2. EMAX: EMAX 1306 RS1306 Version 2 RS1306B 2700KV 4000KV (product page on EMAX’s global store). Retrieved Oct 19, 2026.
3. EMAX: RS1306B-4000KV test report at 12.6 V on an EMAX AVAN 3024 and a Kingkong 3045 (image on EMAX USA’s product page). Throttle steps of 30% to 100%; EMAX’s rpm column is left out because it reads “Max” at full throttle.. Retrieved Oct 19, 2026.
4. EMAX: RS1306B-4000KV test report at 14.8 V on an EMAX AVAN 3024 and a Kingkong 3045 (image on EMAX USA’s product page). Throttle steps of 30% to 100%; EMAX’s rpm column is left out because it reads “Max” at full throttle.. Retrieved Oct 19, 2026.
5. EMAX: RS1306B-2700KV test report at 12.6 V on an EMAX AVAN 3024 and a Kingkong 3045 (image on EMAX USA’s product page). Throttle steps of 30% to 100%; EMAX’s rpm column is left out because it reads “Max” at full throttle.. Retrieved Oct 19, 2026.
6. EMAX: RS1306B-2700KV test report at 16.8 V on an EMAX AVAN 3024 and a Kingkong 3045 (image on EMAX USA’s product page). Throttle steps of 30% to 100%; EMAX’s rpm column is left out because it reads “Max” at full throttle.. Retrieved Oct 19, 2026.