Overview
The SPM Firma 3660 2400Kv Brushless Marine Motor M-SPMXMM1300 is a high-performance brushless outrunner motor purpose-built for RC marine applications. Whether you are piloting a fast attack boat, a racing catamaran, or any other waterborne RC vessel, this motor delivers the speed and reliability that serious RC enthusiasts demand. Spektrum's Firma range has earned recognition across the RC hobby for its engineering excellence and consistent performance, and this 2400Kv variant is no exception. The motor's carefully engineered design ensures smooth power delivery across the operating range, making it an ideal choice for both competitive RC boating UK enthusiasts and recreational pilots looking to upgrade their fleet.
This brushless marine motor is engineered to work seamlessly within a complete RC powertrain setup. With its 2400Kv rating, this motor offers a balanced blend of speed and torque characteristics suitable for medium to high-speed marine applications. The 3660 motor size has become a trusted standard in RC boating circles, offering proven performance in real-world water conditions. When paired with an appropriate Firma brushless smart ESC and quality LiPo battery, this motor transforms your RC boat into a responsive, fast and efficient vessel. The brushless design eliminates the maintenance hassles associated with traditional brushed motors, meaning more time enjoying your boat on the water and less time spent on workshop upkeep.
RC Model Shop stocks this Spektrum Firma motor as part of our comprehensive range of brushless RC motors for every type of vehicle. Whether you are replacing a worn motor, building a new RC boat from a kit, or upgrading an existing setup, we have the expertise and inventory to support your project. Our team understands that choosing the right motor is critical to achieving the performance characteristics you desire, and we are here to guide you through the selection process and provide ongoing technical support.
Key Features
- 3660 Brushless Outrunner Motor Size — The 3660 form factor is a proven marine motor size that balances power output, efficiency and cooling characteristics, making it suitable for a wide variety of RC boat applications from small speedboats to larger multi-hull designs.
- 2400Kv Rating — This Kv specification delivers a strong mid-range power profile that generates excellent speed potential whilst maintaining controlled acceleration and smooth throttle response throughout the RPM range.
- Brushless Technology — Brushless motors eliminate the carbon brushes and commutator found in brushed designs, which means dramatically reduced maintenance, longer motor lifespan, improved efficiency and the ability to run at higher power levels without overheating.
- Marine-Optimised Design — This motor is specifically engineered for RC marine use, with design characteristics that account for the unique demands of waterborne RC applications including saltwater exposure considerations and cooling efficiency in aquatic environments.
- Spektrum Firma Quality — The Firma range represents Spektrum's commitment to precision engineering and quality control, with every motor individually tested to ensure it meets strict performance standards before leaving the factory.
- Compatible with Spektrum ESC Systems — This motor is designed to work alongside Spektrum Firma brushless smart ESCs such as the SPMXSE1160M Firma 160A Smart Brushless Marine ESC, enabling advanced features like programmable throttle curves and telemetry integration.
- Sensored or Sensorless Configuration — This motor can operate with sensored ESC systems for maximum starting torque and smooth low-end power delivery, or with standard sensorless setups for straightforward installation and proven reliability.
Technical Performance
The SPM Firma 3660 2400Kv Brushless Marine Motor represents the pinnacle of modern RC motor engineering for small to medium watercraft applications. At 2400Kv, this motor will reach approximately 355,000 revolutions per minute when supplied with a fully charged 3-cell LiPo battery (nominal 11.1 volts) with no load, though actual RPM under realistic boat loading will be considerably lower depending on propeller pitch, boat weight and water conditions. The brushless outrunner design ensures that the rotating outer bell directly drives your propeller through a simple coupling system, eliminating the need for internal gear reduction whilst maintaining excellent efficiency. This motor size and Kv rating is particularly well-suited to RC boats in the 1.5kg to 4kg displacement range, though it can be adapted for larger or smaller vessels depending on battery capacity and propeller selection. Construction materials throughout the motor emphasise durability and reliability; the machined aluminium bell provides excellent thermal dissipation to keep winding temperatures in check during extended running sessions, whilst the precision-wound stator uses high-quality wire and insulation designed to withstand the electrical stresses of modern high-discharge LiPo batteries. When installed alongside a Firma 160A or equivalent brushless smart ESC rated for at least 3S-4S LiPo chemistry, this motor system will deliver consistent, predictable performance. The motor's mechanical tolerances are held to tight specifications, ensuring smooth rotation with minimal vibration — a critical factor in RC boating where vibration can compromise steering accuracy and increase battery stress. Spektrum's quality assurance process includes 100% motor testing to verify Kv rating, winding resistance and mechanical integrity, giving you confidence that your motor will perform as specified out of the box.
What's in the Box
- SPM Firma 3660 2400Kv Brushless Outrunner Marine Motor
What You Need to Complete
- Spektrum Firma brushless marine ESC (such as the SPMXSE1160M 160A Smart Brushless Marine ESC or similar 100A+ rating)
- 3S or 4S LiPo rechargeable battery pack suitable for marine RC use
- Appropriate propeller matched to your boat's hull design and speed requirements
- Motor coupling or flexible shaft adaptor to connect motor to propeller shaft
- RC boat chassis or hull with motor mount compatible with 3660 brushless motor size
- Radio control system with marine-rated receiver
- LiPo battery charger capable of charging your selected battery chemistry
Frequently Asked Questions
- Is the SPM Firma 3660 2400Kv motor suitable for a beginner RC boater? — Yes, this is an excellent choice for beginners moving from brushed to brushless RC boats. The 2400Kv rating provides good low-end control which makes throttle management easier for newcomers, whilst the brushless design means less maintenance to worry about. Pair it with a quality Spektrum smart ESC that includes programmable throttle curves, and you have a very user-friendly system.
- What battery voltage should I use with this 2400Kv motor? — This motor is designed for 3S LiPo (11.1V nominal) or 4S LiPo (14.8V nominal) battery packs. A 3S setup will provide excellent run time and control characteristics for recreational boating, whilst 4S will deliver significantly more raw speed but slightly reduced efficiency. Do not exceed 4S voltage as this will stress the motor beyond its design limits.
- What size LiPo capacity do you recommend? — For recreational RC boating, a 3000-5000mAh LiPo battery in either 3S or 4S configuration will provide 10-20 minutes of runtime depending on throttle usage and boat weight. Larger batteries offer longer sessions but add weight and cost; smaller batteries are lighter and cheaper but mean more frequent charging.
- How does this motor compare to the Firma 2300Kv variant? — The SPMXMM1200 Firma 2300Kv motor is slightly lower in Kv rating, meaning it will deliver a bit more torque and slightly lower top speed compared to this 2400Kv version. The 2400Kv is the better choice if raw speed is your priority, whilst the 2300Kv suits heavier boats or those where acceleration punch matters more than maximum velocity. Both motors use the same 3660 physical size and will fit any marine chassis designed for 3660 brushless motors.
- What ESC rating do I need for this motor? — We recommend an ESC rated for at least 100A continuous discharge capability. The Spektrum Firma 160A Smart Brushless Marine ESC (SPMXSE1160M) is an excellent choice, offering plenty of headroom and advanced features like programmable thrust curves and telemetry. The Firma 150A and 160A options are premium smart ESCs with the latest firmware and safety features.
- Is this motor sensored or sensorless? — The SPM Firma 3660 2400Kv is compatible with both sensored and sensorless ESC systems. Sensored operation provides slightly smoother startup and better low-RPM control, whilst sensorless setups are simpler and still deliver excellent performance once the motor is spinning.
- How durable is this motor for salt-water boating? — Brushless motors are inherently more salt-water tolerant than brushed designs since they have no commutator to corrode. However, all RC electronics used in salt water should be rinsed with fresh water immediately after use and allowed to dry thoroughly. We recommend using a conformal coating spray on exposed electronics for extended saltwater operation.
- What is the weight of this motor? — The Firma 3660 outrunner is relatively light compared to brushed alternatives, though exact weight specifications are not provided by Spektrum. For most applications, motor weight is less critical than drive system weight since the motor contributes a small percentage of total boat displacement.
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 3660 2400Kv Brushless Marine Motor M-SPMXMM1300 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.
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