Overview
The SPM Firma 780Kv Brushless Motor is a professional-grade inrunner motor specifically engineered for 1/5th scale RC models demanding serious performance and reliability. This is the perfect choice for UK RC enthusiasts looking to build or upgrade a high-powered electric RC car that can handle 8S LiPo battery setups. Whether you're a competitive racer or a dedicated basher, this Spektrum motor delivers the efficiency, durability and raw power that serious RC hobbyists expect from a premium brushless motor.
Featuring advanced engineering and precision manufacturing, the Firma 780Kv motor combines a 4-pole 8-magnet rotor design with a heat-sinking CNC aluminium housing to ensure optimal performance even during extended running sessions. The motor's 780Kv rating strikes an excellent balance between acceleration and top-end speed, making it suitable for a wide range of 1/5th scale applications. Every component has been carefully selected to deliver high durability and smooth rotation, from the precision ball bearings to the hardened steel 8mm output shaft. This is a brushless RC motor that serious hobbyists trust for their most important builds.
This motor comes pre-installed with 6.5mm gold-plated bullet connectors, making integration into your RC setup straightforward and reliable. It's perfectly matched to the Firma 160 Smart ESC, creating a powerful and efficient drivetrain combination that will take your 1/5th scale RC experience to the next level.
Key Features
- Heat-Sinking CNC Aluminium Housing — The motor body is precision machined from aluminium and features integrated heat-sinking fins that actively dissipate heat generated during operation. This design allows the motor to maintain optimal operating temperatures even under sustained high-load conditions, extending the lifespan of internal components and maintaining consistent performance throughout your running sessions.
- 8S LiPo Power Capable — This motor is rated to handle input voltages from 11.1V to 29.6V, which covers the full range from 3S to 8S LiPo battery configurations. This means you have complete flexibility in choosing your power setup, whether you're running a modest 3S pack for casual flying or pushing all the way to 8S for maximum performance and speed on your 1/5th scale RC model.
- High Efficiency Design — With 90% efficiency rating, this motor converts electrical energy into mechanical motion with minimal waste, meaning more of your battery's power goes into driving your RC car forward rather than being lost as heat. This translates to longer run times, cooler motor operation, and better overall performance compared to less efficient motors.
- 4-Pole High-Quality Sintered Rotors — The rotor design uses four poles with sintered magnets, which provides a smooth power delivery curve and excellent torque characteristics. This construction method ensures the magnets are tightly bonded and resistant to degradation, even under the extreme conditions that high-powered RC racing demands.
- 6.5mm Gold-Plated Bullet Connectors — Pre-installed connectors are made from gold-plated materials that provide superior conductivity and corrosion resistance compared to standard connectors. Gold plating ensures a clean electrical connection that minimises resistance and voltage drop, critical factors in delivering maximum power to your motor from your ESC and battery.
- Precision Ball Bearings and Hardened Steel 8mm Shaft — The motor utilises high-quality ball bearings and a durable hardened steel output shaft that can withstand the stresses of high-speed rotation and mechanical load. This combination ensures years of reliable operation with minimal maintenance, a key requirement for serious RC enthusiasts who depend on their equipment.
- Low Cog 4-Pole 8-Magnet Rotor Design — The 8-magnet configuration provides smoother power delivery and better efficiency compared to rotors with fewer magnets. The low centre of gravity design improves overall handling characteristics when integrated into your 1/5th scale RC vehicle.
- Insulated High Purity Copper Windings — The motor's windings are made from high purity copper and properly insulated, maximising electrical conductivity while preventing short circuits. This results in efficient energy transfer and reliable operation under all conditions.
Technical Performance
The Firma 780Kv brushless motor represents a significant step up in performance and build quality compared to budget alternatives. With a maximum continuous current rating of 200A, this inrunner motor is engineered to deliver sustained high-power output, producing 6365W of power when running on a 6S LiPo battery. The 780Kv rating provides an optimal blend of acceleration and top-end speed for 1/5th scale RC cars, delivering approximately 6,240 RPM per volt of applied voltage. The motor measures 56mm in diameter (2.2 inches) and 113mm in length (4.45 inches), weighing 1220g (43oz), which places it in the heavyweight category appropriate for serious 1/5th scale builds. The 8mm hardened steel output shaft provides a robust connection point for your drivetrain components, whilst the precision ball bearings ensure smooth, low-friction rotation even at maximum RPM. The CNC-machined aluminium housing with heat-sinking fins is engineered to handle the thermal demands of continuous high-power operation, crucial for reliability during competitive racing or extended bashing sessions. This is a professional-grade motor that delivers measurable improvements in efficiency, durability and performance over entry-level alternatives.
What's in the Box
- Spektrum Firma 5613-780Kv Sensorless Brushless Motor
- Pre-installed 6.5mm Gold-Plated Bullet Connectors
What You Need to Complete
- Electronic Speed Control (ESC) — The motor is perfectly matched to the Spektrum Firma 160 Smart ESC, though it is compatible with any 200A-rated brushless ESC with 6.5mm bullet connectors
- LiPo Battery — A 3S to 8S LiPo battery pack sized appropriately for your specific RC model
- Battery Charger — A quality LiPo-compatible charger to safely charge your battery pack
- RC Receiver and Radio System — Spektrum DX5R, DX5C or other compatible 2.4GHz radio system
- Motor Mount — Appropriate motor mount assembly for your specific 1/5th scale RC vehicle
- Propeller or Drive Components — Depending on your application (aircraft propeller, car drivetrain gears, etc.)
Frequently Asked Questions
- What does 780Kv mean and how does it affect motor performance? — Kv is an abbreviation for kilovolt, which measures how many RPM the motor will spin per volt of applied electrical voltage. A 780Kv motor spins at approximately 780 RPM for every 1 volt you supply. With an 8S LiPo (29.6V), this motor would theoretically spin at around 23,088 RPM. The Kv rating you choose depends on your application: lower Kv motors (like 780Kv) favour torque and acceleration, whilst higher Kv motors favour top-end speed. For 1/5th scale RC cars, 780Kv represents an excellent compromise between raw speed and usable power delivery.
- Is this motor suitable for beginners or only experienced RC enthusiasts? — Whilst this motor is a high-quality professional-grade component, it is not inherently difficult to use for beginners. However, it is designed for 1/5th scale models and works best when paired with quality ESCs and batteries. If you are new to RC cars, you should ensure you have proper charging equipment, understanding of LiPo battery safety, and appropriate motor mounts and drivetrain components for your specific vehicle. The motor itself is straightforward to install and maintain.
- What battery does this motor need and what is the runtime? — This motor accepts input voltages from 11.1V to 29.6V, meaning it is compatible with 3S, 4S, 5S, 6S, 7S and 8S LiPo batteries. For best performance with this 780Kv motor, most users run either 6S or 8S configurations. Runtime depends on your battery capacity and current draw under load; with a 5000mAh 8S battery, you can typically expect 15-25 minutes of running time depending on driving style and terrain. Always use a quality LiPo charger and follow proper battery safety procedures.
- Does this motor come with everything I need? — The motor includes the brushless motor unit itself and pre-installed 6.5mm gold-plated bullet connectors. You will need to purchase an electronic speed control (ESC) separately—Spektrum's Firma 160 Smart ESC is the perfect match. You will also need a suitable LiPo battery, charger, RC radio system, and appropriate mechanical components such as motor mount, gears and output shaft adapter for your specific vehicle.
- What is the difference between a 780Kv and higher Kv motors like the Firma 1900Kv? — Lower Kv motors like this 780Kv unit produce more torque and acceleration but lower maximum RPM and top speed, making them ideal for heavy 1/5th scale vehicles and situations where you need strong pulling power. Higher Kv motors like a 1900Kv produce less torque but higher RPM and top speed, suiting lighter vehicles or applications where maximum velocity is the priority. The 780Kv Firma represents the sweet spot for 1/5th scale performance.
- How does the efficiency rating affect my RC experience? — The 90% efficiency rating means that 90% of the electrical energy from your battery is converted into mechanical motion, whilst only 10% is lost as heat. This high efficiency translates directly to longer runtime from your batteries, cooler motor operation (reducing thermal stress on components), and more responsive performance. Higher efficiency also means less battery drain, allowing you to run longer sessions before needing to recharge.
- Is this an inrunner or outrunner motor and what is the difference? — This is an inrunner motor, meaning the rotating magnet assembly (rotor) spins inside a stationary coil assembly (stator). Inrunners typically produce higher speeds and lower torque compared to outrunner motors, making them suitable for applications like 1/5th scale cars where speed is important. Outrunner motors have the opposite configuration and are often preferred for aircraft or applications requiring more torque at lower speeds.
Why Buy from RC Model Shop?
RC Model Shop is a trusted UK RC retailer and authorised dealer for all the brands we stock, including Traxxas, ARRMA, Losi, FTX, Hobbywing, Spektrum and more. Based in Walsall, we have a physical store where customers are welcome to come in, view products and purchase in store. Whether you are a seasoned competitor, a weekend basher, or just discovering the world of RC for the first time, our team of experienced RC enthusiasts is here to help you find the perfect setup and provide ongoing support. Order the SPM Firma 780Kv Brushless Motor M-SPMXSM1100 today with confidence, knowing you are buying from an authorised retailer with genuine products, expert knowledge and a commitment to customer satisfaction. Shop online or visit us in Walsall — we look forward to helping you get the most out of your RC experience.
