Delivery Included
1 Year Warranty
The Spektrum M-SPMXSM4200 Firma 5687 1100Kv brushless motor for 1/5 scale 8S RC bashers is engineered for enthusiasts who demand uncompromising torque, thermal resilience, and high-RPM headroom in large-scale surface vehicles. Designed specifically for high-performance platforms such as the ARRMA Kraton 8S EXB and Outcast 8S EXB, the Spektrum M-SPMXSM4200 motor delivers a staggering 7900 watts of output power, making it one of the most capable options for extreme bashing and speed runs. With a sensorless inrunner configuration and a robust 8mm hardened steel shaft, this motor is built to withstand the mechanical stress of oversized gearing and high-current loads. The 5687-size format, combined with a CNC-machined aluminum housing, ensures optimal heat dissipation and structural integrity during prolonged high-load operation. Whether you're pushing past 60 mph or navigating punishing terrain, the Spektrum M-SPMXSM4200 motor offers the precision, durability, and brute force required for elite-level RC performance.
Key features of the Spektrum M-SPMXSM4200
- High-wattage output – supports extreme speed and torque demands for 1/5 scale platforms
- Oversized 8mm shaft – enables drivetrain stability with large pinions and heavy-duty gearing
- Efficient rotor design – delivers consistent torque and smooth throttle response under load
- Thermal-optimized housing – CNC-machined aluminum construction enhances heat dissipation
- OEM fitment – designed for seamless integration with ARRMA Kraton 8S EXB and Outcast 8S EXB
Why is high-wattage output essential for 1/5 scale RC bashers?
The Spektrum M-SPMXSM4200 4-pole motor with 7900W output and CNC aluminum housing is purpose-built to meet the extreme power requirements of 1/5 scale RC vehicles. With a maximum continuous current rating of 95 amps and an efficiency of 86%, this motor delivers sustained torque and top-end speed without compromising thermal stability. The 1100Kv rating ensures a balanced blend of low-end grunt and high-RPM capability, making it ideal for both stunt trucks and speed-focused builds. Whether you're launching off ramps or tearing across open terrain, the Spektrum M-SPMXSM4200 motor maintains consistent performance under the most demanding conditions.
How does the 8mm shaft improve drivetrain durability?
The Spektrum Firma motor with hardened steel shaft and passive cooling for thermal resilience features an oversized 8mm output shaft that is specifically designed to handle the mechanical stress of large-scale gearing. This shaft diameter minimizes flex and wear during aggressive acceleration and high-impact landings, ensuring long-term drivetrain reliability. The hardened steel construction resists deformation and maintains gear alignment, even under extreme torque loads. For users upgrading from smaller shaft motors, the Spektrum M-SPMXSM4200 offers a significant improvement in mechanical integrity and gear engagement stability.
What makes the rotor design ideal for large-scale builds?
The Spektrum M-SPMXSM4200 sensorless inrunner motor with 8mm shaft and D6.5 connectors incorporates a 4-pole rotor configuration that delivers smooth throttle response and consistent torque delivery. This design is critical for maintaining control during rapid acceleration and high-speed maneuvers. The rotor’s efficiency ensures minimal cogging and optimal power transfer, while the sensorless architecture simplifies installation and reduces electronic complexity. With a maximum RPM range of 36,960, the motor provides ample headroom for speed tuning and gear ratio optimization, making it a versatile choice for both bashing and racing applications.
Can the Spektrum M-SPMXSM4200 handle extended high-load use?
The Spektrum M-SPMXSM4200 with low-Kv torque and high-RPM headroom for large-scale builds is equipped with a CNC-machined aluminum housing that enhances thermal management and structural rigidity. This housing design allows the motor to dissipate heat efficiently during prolonged high-current operation, reducing the risk of thermal shutdown or performance degradation. The passive cooling system eliminates the need for external fans, simplifying the setup while maintaining consistent temperature control. For users running 6S–8S LiPo power systems, the Spektrum M-SPMXSM4200 motor offers the thermal resilience needed to sustain peak output across extended sessions.
Is the Spektrum M-SPMXSM4200 compatible with ARRMA EXB platforms?
The Spektrum 1100Kv motor for ARRMA Kraton 8S EXB and Outcast 8S EXB compatibility is confirmed by ARRMA as a standard fitment for their 1/5 scale EXB series. This OEM compatibility ensures proper alignment, gear mesh, and mounting without modification, streamlining the upgrade process for users seeking enhanced performance. The D6.5 bullet connectors provide secure, high-current connectivity with compatible ESC systems, while the motor’s dimensions (56mm diameter × 87mm length) match the chassis requirements of large-scale ARRMA vehicles. For builders focused on drivetrain integrity and performance tuning, the Spektrum M-SPMXSM4200 motor offers a reliable and powerful solution.
What makes this motor a strategic upgrade for 8S stunt trucks?
The Spektrum M-SPMXSM4200 Firma 1100Kv brushless motor for 1/5 scale 8S RC bashers is a strategic upgrade for users seeking to push the limits of speed, torque, and durability. Its high-wattage output supports extreme gearing setups and aggressive driving styles, while the oversized shaft and efficient rotor design ensure drivetrain stability and control. The CNC aluminum housing and passive cooling system provide the thermal resilience needed for extended high-load use, making the motor ideal for stunt trucks and speed rigs operating on 8S LiPo power. For users prioritizing performance and reliability, this motor stands out as the best Spektrum upgrade for drivetrain durability and oversized gearing setups.
For RC enthusiasts ready to elevate their 1/5 scale builds, the Spektrum M-SPMXSM4200 Firma 5687 1100Kv brushless motor for 1/5 scale 8S RC bashers delivers unmatched torque, thermal stability, and OEM fitment precision. Buy Spektrum M-SPMXSM4200 motor for 8S LiPo-powered stunt trucks and speed rigs.
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.
- Most of our products include delivery in the price. If your order is under £90, a small delivery fee will apply but do not worry this will always be clearly shown at checkout before you complete your purchase.
- Depending on what you choose at checkout, your order will usually be delivered either the next working day or within 2 working days. For next day delivery please place your order before 2:00pm. Orders are dispatched Monday to Friday only. Some items may take a little longer and if that is the case we will always show the expected delivery time on the product page.
- If your order includes items with different dispatch times we will normally wait and send everything together once all items are in stock. If one of the items is going to take a while we will give you the choice either wait for everything to arrive or let us send the available items now and deliver the rest later. It is up to you.
- We use trusted delivery partners to make sure your order gets to you safely and on time. We use DPD for next working day deliveries and Royal Mail for the 2 day option.
- As soon as your order is on its way we will send you a tracking number by email. If you provide your mobile number at checkout we will also send delivery updates straight to your phone so you can keep an eye on progress.
- If a product is marked as "Dispatched within 3 working days" delivery usually takes around 3 to 5 working days from when your order is placed.
- For customers in Inverness and other parts of the Scottish Highlands deliveries can take up to 2 working days even if you select next day delivery as couriers do not currently offer a guaranteed next day service to those areas.
