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Firma 85A Brushless Smart ESC / 3300Kv Sensorless Motor Combo

Brand Logo
4.2 out of 5 Customer Rating

Firma 85A Brushless Smart ESC / 3300Kv Sensorless Motor Combo

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Product Details

Spektrum Firma 85A Smart ESC for surface vehicles is waterproof and delivers power and intelligence all-in-one. Without additional sensors or modules, they feed battery and ESC telemetry data straight to your radio in real time, all over one connection. Now includes a compatible 3300Kv Firma Brushless Sensorless motor when you purchase the combo

Product Features

  • Smart all-in-one telemetry
  • Fast, powerful 32-bit ARM M4 processor
  • Waterproof
  • Multiple options for easy programming:
    • Button programming
    • Smart ESC Programming Box
    • SmartLink USB Updating and Programmer application
  • Multi-point protection:
    • Over-current protection
    • Automatic LiPo low-voltage cutoff
    • Thermal protection
    • Failsafe protection
  • Developed and designed by Spektrum™ engineers, in partnership with the industry's leading ESC manufacturer
  • Hand-picked combo for 4WD 1/10th scale surface applications running on 3s Lipo setups
  • Includes high performance and durability Spektrum Firma 3300kV Brushless motor
  • High current adjustable BEC (6v or 7.4v @ 4 Amps)
  • Compact for easy installation in most applications
  • Ready to install — no soldering required
  • Rugged plastic case with mounting tabs
  • Aluminum heat sink for high efficiency
  • Cooling fan
  • Adjustable high-power BEC
  • Firmware updatable through the Smart ESC Programming Box
  • High heat-resistant IC™ connectors, backwards compatible with EC™ connectors
  • Limited 1-year warranty

Product Overview

Like every component in the Spektrum™ Smart ecosystem, Firma™ Smart ESCs combine "plug-and-play" simplicity with the ability to communicate with other Smart electronics — together, creating the best-performing RC system for your vehicle imaginable.

Firma Smart ESCs do much more than regulate power. They function like a virtual engineer inside your model, providing a direct path to the vital operating data you need to reach peak performance. Firma Smart ESCs give you an extra layer of confidence that your electronics are all operating at their best.

With Firma Smart ESCs, you'll be better connected to your vehicle than ever before — without installing extra components that all work independently of each other. You won't need extra wires, modules, or links. A Firma electronic speed control provides a one-wire solution for obtaining telemetry data such as RPM, temperature, battery voltage and capacity.

Firma ESCs not only gather the data but also send it to your transmitter in real time, instead of only storing it for after-run study. You're able to adjust settings as needed to boost performance on the go. The Firma Smart single-wire telemetry solution has been tested for quality and performance by the best brands in RC. Their verdict? Smart technology is both simpler and superior!

Needed to Complete
  • Spektrum™ Surface Receiver
  • Spektrum Smart Technology LiPo Battery
  • Spektrum Transmitter
What's in the Box?
  • (1) Spektrum™ Firma™ Smart ESC
  • (1) Spektrum Smart sticker sheet
  • (1) Product Manual

Video Overview



The all-weather, waterproof design of Spektrum™ Firma™ Smart ESCs allows them to perform in nearly any terrain under almost any conditions. Firma ESCs keep you going through dust, gravel, snow, and water.



Firma™ ESCs feature IC™ series battery connectors. The IC series of connectors are designed from the ground up to provide a more solid connection, higher heat resistance, and effortless installation. When used with an IC3™ or IC5™ connector-equipped Spektrum™ Smart battery, the ESC can receive and transmit battery telemetry data. EC3 and EC5 are also compatible with Firma ESCs for basic operation and ESC telemetry.



No need to connect multiple wires, sensors, modules, and links. With Firma™ ESCs, simple one-wire telemetry transmits a wide range of data directly to your transmitter in real time, including RPM, voltage, temperature, balance, capacity, and speed.*

*See compatibility chart for more information.



When used with a Spektrum™ Smart LiPo battery, your Firma™ ESC provides you with the benefit of battery telemetry that's automatically transmitted to your compatible Spektrum radio in real time. On your transmitter screen you'll be presented with helpful information such as number of cycles, battery percentage, individual cell voltage and more!



Multiple programming options are available. Button programming can be used with nothing more needed. Using the Smart Firma™ ESC Programming Box, you can easily change settings at the track to suit driving conditions. An easy-to-use Smart Link USB Updating and PC Programmer app is also available.



The Firma™ ESCs' 32-bit M4 processor produces higher resolution signal input and more accurate motor output.


Product Specifications

Manufacturer # 605482692387
Adjustable Timing No
Battery Type LiPo (3.7V per cell)
Brakes Yes
Integrated ESC No
Constant Wattage 750-999W
Maximum Burst Current 550A
Maximum Continuous Current 33A
Motor Type Brushless
Programmable Yes
Programming Options Button, Programming Box, Smartlink App, On Screen Text Gen
Connector Type IC3
Efficiency 82%
ESC Type Brushless
Motor Class 1/10 Scale
Product Length 1.7" (43 mm)
Forward Yes
Reverse Yes
Wire Gauge 12 AWG
Battery Input Lead IC3
Outer Diameter 1.41" (36 mm)
Product Width 2.1" (53 mm)
Technology Smart
BEC Continous Current 4
Low-Voltage Cutoff Programmable Yes
Number of Poles 4
Output 430W(2S), 780W(3S)
Product Weight 0.255
Shaft Diameter 0.125" (3 mm)
Water-Resistant Yes
Application Surface
Auto Cutoff Yes
BEC Maximum Burst Current 8A
BEC Voltage 6V/7.4V
Drive Type Forward/Brake/Reverse
Input Voltage 2-3S LiPo, do not exceed 3S (11.1V) with this motor
Kv Rating 3000Kv or more
Motor Output Lead 4
Part Type Electronics
Product Application Surface
Product Height 1.3" (33 mm)
RPM/Volt (Kv) 38,400 @ 12V
Sensored No
Sensor Type Sensorless
Time Delay Brake Yes
Amperage 80A - 99A
BEC Type Switch Mode
Max Input Voltage 11.1V
Motor Design Inrunner