3–3.5-inch FPV motor

EMAX RS1408

A 14 g micro racing motor for 3 to 3.5-inch props: 1408 stator, 9N12P, single-strand windings, and up to 800 g of pull on EMAX’s 25.2 V bench (2300KV, AVAN 3.5 × 2.8 × 3).

3 to 3.5-inch micro racing
6S (2300KV) or 4S (3600KV)

Drawing the 3D model…

Throttle60%

The spin is an illustration: the model turns at 1/600 of the no-load speed, and it is a generic 1408 motor drawn from EMAX’s published sizes, not its exact design. Thrust, current and power are EMAX’s bench figures for the AVAN 3.5×2.8×3 prop at 25.2 V, read straight across between its throttle steps. Its data starts at 30% throttle.

Version

2300KV5S–6S3600KV

EMAX tested it at 21 V and 25.2 V; its 800 g max thrust is this KV on an AVAN 3.5 × 2.8 × 3 at 25.2 V.

Max thrust: 800 g; AVAN 3.5×2.8×3 prop, 25.2 V
Weight: 14 g; without leads; the leads add 1.0 g
Peak current: 20.0 A; full throttle
Max power: 504 W; full throttle

Plain links: we earn nothing from them.

What it pulls

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

At 60% with the AVAN 3.5×2.8×3: 402 g of thrust, 6.2 A, 156 W, 2.57 g per watt.

On your quad

All-up weight650 g

4.9 : 1

Thrust to weight at full throttle: four motors pull 3,200 g with the AVAN 3.5×2.8×3 at 25.2 V.

At 60% throttle they pull 1,608 g, 2.5 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

800 g on 6S
At 25.2 V the 2300KV pulled 800 g at full throttle on an AVAN 3.5 × 2.8 × 3, drawing 20 A; the 3600KV pulled 770 g on the same prop at 16.8 V and 28 A.
Source: EMAX 2300KV test report, EMAX 3600KV test report
Between micro and 22xx
EMAX built the 1408 to bridge micro motors and 22xx motors, so micro quads can carry heavier loads such as HD cameras; it says AVAN props fit it on builds from 2 to 4 inches.
Source: EMAX USA product page
3.8 g/W at 30%
At 12.6 V on the AVAN 3.5 × 2.8 × 3 the 3600KV made 77 g at 30% throttle, at 3.82 g/W.
Source: EMAX 3600KV test report

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 2300KV drew up to 20 A at 25.2 V and the 3600KV up to 28 A at 16.8 V, both on the AVAN 3.5 × 2.8 × 3; a 30 A ESC covers either. (EMAX 2300KV test report, EMAX 3600KV test report)
Props: 3 to 3.5-inch props, per EMAX. It tested both KVs on an AVAN 3.5 × 2.8 × 3, a Kingkong 3045 and an AVAN Mini; the 3.5-inch AVAN pulled most at every voltage. (EMAX USA product page, EMAX 2300KV test report, EMAX 3600KV test report)
Battery: EMAX’s spec list gives 5S–6S, which matches the 2300KV’s tests at 21 V and 25.2 V; it tested the 3600KV at 12.6 V and 16.8 V (3S and 4S). (EMAX USA product page, EMAX 2300KV test report, EMAX 3600KV test report)

Where to buy

EMAX USAthe maker’s US store; 2300KV (listed as sold out)
$10.99seen Oct 19, 2026
Visit
EMAXthe maker’s global store; 2300KV and 3600KV (both listed as out of stock)
$10.78seen Oct 19, 2026
Visit

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

Full specs

Spec	Value	Source
KV	2,300 rpm/V (also 3600KV)	EMAX USA product page, EMAX product page
Stator	14 × 8 mm (1408)	EMAX USA product page, EMAX product page
Configuration	9N12P (9 stator slots, 12 magnet poles)	EMAX USA product page, EMAX product page
Battery	5S–6S LiPo (EMAX’s spec list, for both KVs; it tested the 2300KV at 21 V and 25.2 V and the 3600KV at 12.6 V and 16.8 V)	EMAX USA product page, EMAX product page
Weight	14 g (without leads; the leads add 1.0 g)	EMAX USA product page, EMAX 2300KV test report, EMAX 3600KV test report
Dimensions	φ18.4 × 22.4 mm (EMAX’s diameter and length)	EMAX USA product page, EMAX product page
Shaft	1.5 mm	EMAX USA product page, EMAX product page
Winding	Single-strand	EMAX 2300KV test report, EMAX 3600KV test report
Idle current	0.53 A (at 10 V, turning 23,250 rpm unloaded; 3600KV 1.03 A at 10 V (35,890 rpm))	EMAX 2300KV test report
Leads	26 AWG silicone wire, 90 mm	EMAX 2300KV test report, EMAX 3600KV test report

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.

2300KV on 5S–6S6 props

Prop	Current (A)	Thrust (g)	Efficiency (g/W)	Power (W)	Throttle
AVAN 3.5×2.8×3at 25.2 V	1.3	119	3.63	32.8	30%
	2.5	204	3.24	63	40%
	4.2	312	2.95	105.8	50%
	6.2	402	2.57	156.2	60%
	8.1	477	2.34	204.1	70%
	10.7	560	2.08	269.6	80%
	13.4	630	1.87	337.7	90%
	20	800	1.59	504	100%
AVAN Miniat 25.2 V	1.1	82	2.96	27.7	30%
	2	152	3.02	50.4	40%
	3.3	233	2.8	83.2	50%
	5.1	320	2.49	128.5	60%
	6.6	385	2.31	166.3	70%
	8.6	468	2.16	216.7	80%
	11.4	560	1.95	287.3	90%
	15.8	690	1.73	398.2	100%
AVAN 3.5×2.8×3at 21 V	1.1	85	3.68	23.1	30%
	2	142	3.38	42	40%
	3.4	234	3.28	71.4	50%
	4.6	298	3.08	96.6	60%
	6.1	364	2.84	128.1	70%
	8.2	434	2.52	172.2	80%
	10.9	523	2.28	228.9	90%
	15.2	667	2.09	319.2	100%
Kingkong 3045at 25.2 V	1.1	81	2.92	27.7	30%
	2.1	151	2.85	52.9	40%
	3.3	216	2.6	83.2	50%
	4.8	292	2.41	121	60%
	6.1	340	2.21	153.7	70%
	7.8	407	2.07	196.6	80%
	10.1	491	1.93	254.5	90%
	14.5	658	1.8	365.4	100%
AVAN Miniat 21 V	0.8	55	3.27	16.8	30%
	1.5	104	3.3	31.5	40%
	2.5	162	3.09	52.5	50%
	3.5	220	2.99	73.5	60%
	4.8	282	2.8	100.8	70%
	6.5	353	2.59	136.5	80%
	8.6	430	2.38	180.6	90%
	11.6	531	2.18	243.6	100%
Kingkong 3045at 21 V	0.9	56	2.96	18.9	30%
	1.5	98	3.11	31.5	40%
	2.5	153	2.91	52.5	50%
	3.5	206	2.8	73.5	60%
	4.7	258	2.61	98.7	70%
	5.9	310	2.5	123.9	80%
	8.1	390	2.29	170.1	90%
	10.8	499	2.2	226.8	100%

Source: EMAX 2300KV test report

3600KV6 props

Prop	Current (A)	Thrust (g)	Efficiency (g/W)	Power (W)	Throttle
AVAN 3.5×2.8×3at 16.8 V	2.3	119	3.08	38.6	30%
	4.1	193	2.8	68.9	40%
	6.2	280	2.69	104.2	50%
	8.1	345	2.54	136.1	60%
	11	428	2.32	184.8	70%
	15.1	505	1.99	253.7	80%
	19.3	590	1.82	324.2	90%
	28	770	1.64	470.4	100%
AVAN Miniat 16.8 V	1.8	87	2.88	30.2	30%
	3.3	145	2.62	55.4	40%
	4.9	215	2.61	82.3	50%
	6.6	278	2.51	110.9	60%
	8.8	342	2.31	147.8	70%
	12.4	432	2.07	208.3	80%
	16.2	525	1.93	272.2	90%
	23.2	670	1.72	389.8	100%
Kingkong 3045at 16.8 V	2	84	2.5	33.6	30%
	3.4	140	2.45	57.1	40%
	4.9	203	2.47	82.3	50%
	6.5	260	2.38	109.2	60%
	8.4	312	2.21	141.1	70%
	11.6	394	2.02	194.9	80%
	14.9	483	1.93	250.3	90%
	20.9	635	1.81	351.1	100%
AVAN 3.5×2.8×3at 12.6 V	1.6	77	3.82	20.2	30%
	2.6	121	3.69	32.8	40%
	3.9	170	3.46	49.1	50%
	5.6	231	3.27	70.6	60%
	7.9	300	3.01	99.5	70%
	11.1	384	2.75	139.9	80%
	14.4	450	2.48	181.4	90%
	19.6	550	2.23	247	100%
AVAN Miniat 12.6 V	1.2	53	3.51	15.1	30%
	2.1	89	3.36	26.5	40%
	3	130	3.44	37.8	50%
	4.5	180	3.17	56.7	60%
	6	230	3.04	75.6	70%
	8.6	300	2.77	108.4	80%
	11.5	375	2.59	144.9	90%
	15.1	439	2.31	190.3	100%
Kingkong 3045at 12.6 V	1.3	53	3.24	16.4	30%
	2.2	85	3.07	27.7	40%
	3	120	3.17	37.8	50%
	4.3	164	3.03	54.2	60%
	6	216	2.86	75.6	70%
	8.1	270	2.65	102.1	80%
	10.7	330	2.45	134.8	90%
	14.1	404	2.27	177.7	100%

Source: EMAX 3600KV test report

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)
Stator. The coils are wound on a stack of thin steel laminations: 14 × 8 mm (1408). (EMAX USA product page, EMAX product page)
Winding. Single-strand. (EMAX 2300KV test report, EMAX 3600KV test report)

How fast it spins

KV is the motor’s no-load speed per volt. With nothing on the shaft, the 2300KV 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	34,040	3,404 Hz	20,424
4S full	16.8	38,640	3,864 Hz	23,184
6S nominal	22.2	51,060	5,106 Hz	30,636
6S full	25.2	57,960	5,796 Hz	34,776

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 14 × 8 mm stator, 18.4 mm bell, 1.5 mm shaft 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.