HappyModel EX1202.5

What you get

• Crux3 and Cine8 motor

  The 6400KV is the original motor of HappyModel's Crux3, the 8000KV of its Cine8.

  Source: HappyModel product page

• Stepped shaft

  1.5 mm where the prop goes, 2 mm inside the motor.

  Source: HappyModel product page

• 4.4 g

  HappyModel lists 4.4 g per motor.

  Source: HappyModel product page

• Bench data for each KV

  110 g on 7.4 V (6400KV, Gemfan 3018), 127.8 g on 11.1 V (8000KV, 48 mm three-blade), 55.2 g on 3.7 V (11000KV, 65 mm two-blade).

  Source: HappyModel bench data

What to pair it with

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

ESC

HappyModel's bench tops out at 7.2 A (8000KV on 11.1 V), 4.5 A (6400KV on 7.4 V) and 3.92 A (11000KV on 3.7 V). An ESC rated above 7.2 A per motor covers each, if it takes that version's battery. (HappyModel bench data)

Props

HappyModel tested a Gemfan 3018 two-blade on the 6400KV, 48 mm three-blade props on the 8000KV and 65 mm two-blade props on the 11000KV. (HappyModel bench data)

Battery

2S–3S for 6400KV and 8000KV, 1S only for 11000KV. (HappyModel product page)

Frame

Four M2 screws on a 9 mm circle. (HappyModel drawing)

Where to buy

• RaceDayQuads6400KV, CW
  price on the store’s page
  Visit
• GetFPV6400KV, 8000KV or 11500KV, CW
  price on the store’s page
  Visit

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

Full specs

Bench data

Redrawn from HappyModel’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 outside the motor, 2 mm inside. (HappyModel product page)
• Stator. The coils are wound on a stack of thin steel laminations: 12 × 2.5 mm (1202.5). (HappyModel product page)
• Base. 4 × M2 holes on a 9 mm circle. (HappyModel drawing)

How fast it spins

KV is the motor’s no-load speed per volt. With nothing on the shaft, the 6400KV 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 HappyModel’s published sizes: the 12 × 2.5 mm stator, 15 mm bell, 9.5 mm height, 1.5 mm shaft, 9 mm mounting circle and 9 teeth and 12 magnets. Anything HappyModel 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. HappyModel: EX1202.5 KV6400 KV8000 KV11000 brushless motors (product page, spec list). Retrieved Oct 19, 2026.
2. HappyModel: EX1202.5 dimension drawing (image on the product page). Retrieved Oct 19, 2026.
3. HappyModel: EX1202.5 bench data (image on the product page; its last column, headed Throttle, is left out). Retrieved Oct 19, 2026.
4. HappyModel: EX1202.5 main product photo, used for finish. Retrieved Oct 19, 2026.