Overview
The SPM Firma Brushless Motor, 3652 3800Kv 4-pole (model M-SPMXSM3200) is a high-performance brushless motor specifically engineered as a direct replacement for the Losi Promoto-MX/SM motorcycle. Whether you're replacing a worn-out motor or upgrading your brushless RC motorcycle, this Spektrum Firma motor delivers the power and reliability that serious RC enthusiasts demand. This is an ideal choice for anyone looking to maintain peak performance in their small-scale RC motorcycle or for those seeking a genuine OEM replacement motor from Spektrum, a recognised leader in RC technology and innovation.
Brushless motors have revolutionised the RC hobby, offering superior efficiency, longer runtimes, and minimal maintenance compared to traditional brushed motors. The Firma 3652 3800Kv motor represents the pinnacle of Spektrum's motor engineering, combining precision manufacturing with proven performance characteristics. If you're serious about getting the best from your RC motorcycle, this brushless motor is the upgrade your setup needs. The 3800Kv rating means rapid acceleration and responsive handling, making it perfect for both casual bashers and competitive RC enthusiasts in the UK.
This motor is built to work seamlessly with compatible ESC units and lithium polymer battery systems, making integration into your existing RC car UK setup straightforward. Spektrum's reputation for quality means you're investing in a motor that will deliver consistent, reliable performance season after season.
Key Features
- 4-pole brushless construction — The four-pole design delivers smooth power delivery and improved efficiency compared to lower pole-count alternatives, ensuring your Promoto-MX/SM responds instantly to throttle input and maintains consistent performance throughout the charge cycle.
- 3800Kv rating — This Kv specification means the motor will spin approximately 3800 RPM per volt applied, providing rapid acceleration and high-speed capability that transforms how your motorcycle performs on the track or trail.
- 3652 motor size — The standardised 3652 form factor is specifically designed for small-scale RC motorcycles like the Losi Promoto-MX/SM, ensuring perfect fitment and alignment with your vehicle's motor mount.
- Direct replacement compatibility — Engineered as a drop-in replacement for the Losi Promoto-MX/SM, this motor eliminates guesswork and compatibility issues, allowing you to restore or upgrade your motorcycle with confidence.
- 4mm bullet connectors — The industry-standard 4mm bullet connector type makes installation quick and straightforward, allowing fast swaps between motors or simple testing and configuration changes.
- Spektrum quality assurance — Manufactured by Spektrum, a trusted name in RC electronics and motors, this brushless motor has been engineered to strict quality standards and tested for reliability under demanding conditions.
Technical Performance
The Firma 3652 3800Kv brushless motor is a precision-engineered component designed for optimal performance in small-scale RC motorcycles. With an outer diameter of 36 millimetres (1.41 inches) and a total length of 60 millimetres (2.36 inches), this compact motor is engineered to fit snugly within the Losi Promoto-MX/SM's chassis without modification. The motor's 5 millimetre (0.197 inch) shaft diameter is a standard specification that mates with compatible pinions and drivetrain components. The brushless design eliminates carbon brush wear, meaning you'll enjoy thousands of hours of running time before any maintenance is required — a significant advantage over traditional brushed motors. With an output rating of 1150 watts on a 3S LiPo battery, this motor delivers substantial power while maintaining thermal stability. The 3800Kv rating ensures rapid motor response and acceleration, essential qualities for competitive riding or high-energy bashing sessions. The motor is designed to work with standard RC ESC units and 3-cell lithium polymer batteries, making it a compatible upgrade or replacement within the ready to run RC motorcycle ecosystem. Built with quality windings and precision engineering, the Firma motor maintains consistent performance across extended run sessions and delivers the reliability that Spektrum is known for throughout the RC hobby.
What's in the Box
- Firma 3652 3800Kv 4-Pole Brushless Motor
Frequently Asked Questions
- Is the Firma 3652 3800Kv motor suitable for beginners? — The Firma brushless motor is an excellent choice for riders of all skill levels. The 3800Kv rating provides responsive performance that beginners can enjoy whilst offering the power and reliability that experienced riders demand. As a direct replacement for the Losi Promoto-MX/SM, installation is straightforward for anyone familiar with basic RC maintenance.
- What battery does the Firma 3652 motor require? — The motor is rated for 3S LiPo (lithium polymer) battery systems. This is the standard battery type for small-scale RC motorcycles, and the 1150-watt output on 3S provides excellent performance and runtime. Always ensure your chosen ESC is compatible with 3S LiPo batteries before operation.
- What makes brushless motors better than brushed alternatives? — Brushless motors like the Firma 3652 offer several advantages: they require virtually no maintenance (no brush replacement), deliver more consistent power throughout the battery discharge cycle, generate less heat, and typically provide longer overall lifespan. The efficiency gains also translate to better runtime from your batteries.
- Will this motor fit my Losi Promoto-MX/SM? — Yes, the Firma 3652 3800Kv is engineered as a direct replacement motor for the Losi Promoto-MX/SM. The 36-millimetre outer diameter and 60-millimetre length match the stock motor specifications, and the 5-millimetre shaft diameter aligns with your motorcycle's drivetrain. Installation should be a straightforward swap.
- What is the difference between the 3652 and other motor sizes? — The 3652 designation refers to the motor's physical dimensions (36 millimetre diameter, 52 millimetre length). This size is optimised for small-scale RC motorcycles and buggies. Larger numbers like 3660 indicate different outer diameters or lengths, which would not fit the same motor mounts. The 3652 is the correct size for your Promoto-MX/SM.
- Does this include an ESC? — No, the Firma 3652 motor is sold as a motor-only component. You will need a compatible brushless ESC rated for 3S LiPo operation. The 4mm bullet connectors on this motor are industry-standard and will connect to any quality RC ESC with matching connectors.
- What output power should I expect? — The Firma 3652 delivers 1150 watts of output power when running on a 3S LiPo battery system. This substantial power output is ideal for fast acceleration and high-speed performance, whether you're racing competitively or enjoying casual bashing sessions.
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 Brushless Motor, 3652 3800Kv 4-pole, Motorcycle M-SPMXSM3200 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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