Spektrum Firma 85A Brushless Smart ESC / 3300kv Sensorless Motor Combo

Quantity: Only 4 left in stock.




Like every component in the Spektrum(TM) Smart ecosystem, Firma(TM) 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!



  • 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(TM) 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(TM) connectors, backwards compatible with EC(TM) connectors
  • Limited 1-year warranty



The all-weather, waterproof design of Spektrum(TM) Firma(TM) 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.


EC3(TM)/EC5(TM) Backwards Compatible

Firma(TM) ESCs feature IC(TM) 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(TM) or IC5(TM) connector-equipped Spektrum(TM) 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.


One-wire Telemetry

No need to connect multiple wires, sensors, modules, and links. With Firma(TM) 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.


Smart Technology Battery Data

When used with a Spektrum(TM) Smart LiPo battery, your Firma(TM) 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

Multiple programming options are available. Button programming can be used with nothing more needed. Using the Smart Firma(TM) 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.


Fast and Power M4 Processor

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


Product Specifications

  • Adjustable Timing     No
  • Maximum Burst Current     550A
  • Maximum Continuous Current     33A
  • Motor Type     Brushless - Sensorless
  • Technology     Smart
  • Efficiency     82%
  • Product Length     1.7" (43 mm)
  • Connector Type     IC3
  • Product Width     2.1" (53 mm)
  • Outer Diameter     1.41" (36 mm)
  • Battery Input Lead     12AWG 5.1" (130mm)
  • Motor Output Lead     12AWG 5.1 in (130mm)
  • Product Height     1.3" (33 mm)
  • RPM/Volt (Kv)     38,400 @ 12V
  • Time Delay Brake     Yes
  • BEC     Yes
  • Input Voltage     2-3S LiPo, do not exceed 3S (11.1V) with thtis motor
  • Drive Type     Forward/Brake/Reverse
  • BEC Maximum Burst Current     8A
  • BEC Voltage     6V/7.4V
  • Battery Type     LiPo (3.7V per cell)
  • Brakes     Yes
  • Programmable     Yes
  • BEC Type     Switch Mode
  • Motor Design     Inrunner
  • Reverse     Yes
  • Forward     Yes
  • Wire Gauge     12 AWG
  • Auto Cutoff     Yes
  • BEC Continous Current     4A
  • 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


Needed to Complete

  • Spektrum(TM) Surface Receiver
  • Spektrum Smart Technology LiPo Battery
  • Spektrum Transmitter


What's in the Box?

  • (1) Spektrum(TM) Firma(TM) Smart ESC
  • (1) Spektrum Smart sticker sheet
  • (1) Product Manual


Used with permission, copyright ©2022 Horizon Hobby, Inc. Copyright ©2022 Brey Corp. t/a Hobby Works.®

$6 Flat Rate Shipping. FREE Over $199* Most Items