Overview
The SPM FIRMA 2400KV 4-Pole Brushless Motor (model M-SPMXSM2100) from Spektrum Accessories is a high-performance brushless motor designed for RC enthusiasts looking to upgrade their RC car or replace an existing motor with a reliable, quality component. This 3668-sized brushless motor delivers impressive performance with its 2400KV rating, making it suitable for a wide range of RC applications. Whether you're a dedicated RC racer, weekend basher, or someone exploring the world of brushless RC motors for the first time, this Spektrum motor offers the quality and performance you expect from an authorised Spektrum dealer.
Brushless motors have become the standard choice for serious RC car UK enthusiasts because they offer superior efficiency, longer runtime, and reduced maintenance compared to brushed alternatives. The FIRMA 2400KV motor embodies this technology with its four-pole construction, which optimises power delivery and responsiveness. This motor is ideal for those seeking to enhance their ready to run RC setup or build a custom RC vehicle with proven, reliable components. The 4-pole configuration provides smooth acceleration and consistent performance across a wide range of throttle inputs, making it an excellent choice for both competitive racing and recreational driving.
Spektrum is a recognised leader in RC electronics and motors, and this FIRMA motor reflects their commitment to quality engineering and performance. The motor has earned a 5 out of 5 customer rating, demonstrating that RC enthusiasts trust and value this component. At RC Model Shop, we stock genuine Spektrum products and are committed to helping you find the right motor for your specific RC needs, whether you're upgrading an existing vehicle or building a new one from scratch.
Key Features
- 2400KV Rating — This KV (kilovolt) specification determines the motor's speed characteristics and is crucial for matching your motor to your intended application, gearing, and battery setup. A 2400KV motor sits in the mid-range for brushless RC motors, providing a good balance between speed and torque for general-purpose RC use without requiring extreme gearing adjustments.
- 4-Pole Brushless Design — The four-pole configuration delivers smoother power delivery and more consistent performance throughout the acceleration range compared to lower pole-count alternatives. This design results in better throttle response and more predictable handling characteristics, which is especially valuable if you're racing or driving technically challenging courses.
- 3668 Motor Size — This size designation (36mm diameter, 68mm length) is a standard specification in the RC hobby that ensures compatibility with a wide range of motor mounts and vehicle frames. The compact yet substantial size provides excellent power-to-weight ratio for most RC applications.
- Brushless Motor Technology — Brushless motors eliminate the brushes and commutator found in brushed motors, resulting in higher efficiency, longer lifespan, less heat generation, and virtually maintenance-free operation. This means you'll spend less time maintaining your motor and more time enjoying your RC car UK experience.
- High-Quality Spektrum Construction — Built to the exacting standards Spektrum is known for, this motor features quality materials and precision engineering that ensure reliable performance over extended periods of use and across demanding driving conditions.
Technical Performance
The FIRMA 2400KV brushless motor represents a mature, well-engineered solution for RC enthusiasts seeking reliable power delivery. With its 4-pole architecture, the motor is optimised to provide smooth torque characteristics and efficient power conversion. The 2400KV rating positions this motor ideally for applications requiring a balance between acceleration and top-end speed, making it versatile across different RC vehicle types and driving styles. The brushless design eliminates the wear and tear associated with traditional brushed motors, meaning no brush replacement, minimal friction losses, and extended operational life. This motor works seamlessly with compatible brushless ESCs and lithium polymer or lithium iron battery packs commonly used in modern RC cars. The efficient power delivery of brushless technology means more of your battery's energy converts to motion rather than heat, extending runtime and improving performance consistency throughout a charge cycle. For RC car enthusiasts in the UK looking to upgrade to brushless performance or replace an existing motor, the FIRMA 2400KV delivers the quality, reliability, and proven performance that serious hobbyists demand. The motor's construction quality and engineering excellence make it suitable for both recreational bashing and competitive racing applications.
What's in the Box
- SPM FIRMA 2400KV 4-Pole Brushless Motor (3668 size)
What You Need to Complete
- Brushless ESC (Electronic Speed Controller) compatible with your battery voltage and current requirements
- LiPo or LiFe battery pack (2S or 3S depending on your specific setup and vehicle requirements)
- Motor mount compatible with 3668-sized motors for your specific RC vehicle
- RC car or vehicle frame designed to accept this motor size
- Radio system and receiver for vehicle control
- Cooling heatsink (optional but recommended for extended use — such as the Spektrum SPMXSMH1 motor heatsink designed for 3660-sized motors)
Frequently Asked Questions
- What does the 2400KV rating mean and how does it affect performance? — The KV rating indicates how many RPM (revolutions per minute) the motor will turn per volt of input. A 2400KV motor will spin faster with higher voltage batteries but is geared towards moderate speeds compared to higher KV motors. This rating is ideal for applications where you want balanced acceleration and top speed without excessive heat generation, making it suitable for general-purpose RC car UK use across various vehicle types.
- Is the FIRMA 2400KV brushless motor suitable for beginners? — Yes, this motor is an excellent choice for those new to brushless RC systems. The 2400KV rating is forgiving and doesn't demand extreme ESC capability or rare battery specifications. As a brushless motor, it requires minimal maintenance compared to brushed alternatives, making it ideal for beginners who want reliable performance without complex upkeep. The 4-pole design also provides smooth, predictable power delivery, which helps new drivers develop better control techniques.
- What battery does this motor need? — The FIRMA 2400KV motor is compatible with 2S and 3S LiPo (lithium polymer) battery packs, which are the standard power source for modern brushless RC vehicles. The exact battery capacity and discharge rating you choose will depend on your specific vehicle weight, gearing, and intended use. Always ensure your ESC is rated for the voltage of your chosen battery pack.
- What is the difference between this 4-pole motor and lower pole-count alternatives? — Four-pole brushless motors provide smoother acceleration and more consistent torque delivery across the RPM range compared to 2-pole or 3-pole designs. This means better throttle response, more predictable handling, and reduced cogging (the slight hesitation some motors exhibit at low speeds). For RC enthusiasts wanting refined performance and easier drivability, 4-pole motors represent a superior choice.
- Do I need a heatsink for this motor? — For casual recreational driving, the motor can operate without a heatsink. However, for extended use periods, competitive racing, or hot weather conditions, a motor heatsink is recommended to dissipate heat and maintain optimal performance. The optional Spektrum SPMXSMH1 motor heatsink is designed for compatible Spektrum motor sizes and helps prolong motor lifespan.
- What ESC should I pair with this motor? — You'll need a brushless ESC rated for your chosen battery voltage (2S or 3S) and with sufficient current capacity for your vehicle setup. Spektrum offers compatible brushless ESCs such as the FIRMA 40A ESC, which is waterproof and supports 2S-3S operation, making it an ideal pairing for this motor.
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 2400KV 4-POLE BL MOTOR, 3668 M-SPMXSM2100 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.
We want to make sure your delivery goes smoothly, so here are some important details about our service:
- For orders above £120, we offer delivery to most mainland UK addresses. For orders under £120, we can still deliver to Northern Ireland and the outlying isles, as long as the item can be sent by Royal Mail, weighs less than 30kg, and fits within 61cm × 46cm × 46cm. Some highland and remote areas may carry an extra delivery charge as couriers often apply surcharges in these locations. If you live in one of these areas, feel free to contact us before ordering so we can confirm the delivery options and costs for you.
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