Delivery Included
1 Year Warranty
The Spektrum P-SPMX-1075 4685 marine motor with 740Kv rating, 4-pole design, and water-cooled housing is engineered for serious RC boat enthusiasts who demand uncompromising performance from their propulsion systems. Designed specifically for high-power marine applications, this brushless motor delivers the torque, speed, and thermal stability required to dominate open water. With a robust 85mm length and precision-machined 5mm alloy steel shaft, the motor is built to handle the demands of 12S LiPo setups without sacrificing efficiency or reliability. Whether you're racing across flat water or navigating unpredictable currents, the Spektrum P-SPMX-1075 offers a balanced blend of power and control that elevates your RC boating experience.
Key features of the Spektrum P-SPMX-1075 4685 marine motor
- Water-cooled housing – maintains optimal operating temperature during high-load runs
- 4-pole rotor design – delivers smooth torque and consistent acceleration
- 85mm motor length – increases torque output for larger hulls and aggressive setups
- 5mm alloy steel shaft – ensures durable torque transfer and resistance to flex
- 8mm bullet connectors – simplifies installation and ensures secure power delivery
- 740Kv rating – optimized for high-speed 12S LiPo configurations
- Compact 2.22" diameter – fits seamlessly into streamlined marine builds
Why does the Spektrum P-SPMX-1075 excel in high-power marine setups?
The Spektrum P-SPMX-1075 brushless motor for 12S LiPo-powered high-performance RC boats is purpose-built to handle the extreme demands of high-voltage propulsion systems. With a Kv rating of 740, the motor is tuned for speed and torque balance, making it ideal for large-scale boats that require rapid acceleration and sustained top-end performance. The 4-pole rotor design enhances torque delivery while minimizing cogging, ensuring smooth and predictable throttle response. This combination of features makes the motor a reliable choice for competitive racing and high-speed recreational use alike.
How does water cooling improve performance and longevity?
Thermal management is critical in high-powered marine environments, and the Spektrum P-SPMX-1075 4685 marine motor with 740Kv rating, 4-pole design, and water-cooled housing addresses this with an integrated water-cooling system. By actively dissipating heat during operation, the motor maintains lower internal temperatures, which helps preserve component integrity and prevent performance degradation. This feature is especially valuable during extended runs or in warm climates, where overheating can compromise motor efficiency and lifespan. The water-cooled housing ensures that the motor remains stable and responsive, even under continuous load.
What makes the 4-pole rotor design ideal for marine propulsion?
The Spektrum high-torque marine motor with 4-pole design, 85mm length, and steel output shaft utilizes a four-pole rotor to deliver consistent torque across the entire RPM range. This design reduces vibration and improves low-speed control, which is essential for maneuvering in tight spaces or launching from a standstill. The increased pole count also contributes to smoother acceleration and better throttle modulation, giving users more precise control over their boat’s movement. Whether you're navigating technical courses or open water, the 4-pole configuration ensures reliable and efficient propulsion.
How does the shaft construction support high-load applications?
The Spektrum P-SPMX-1075 5mm steel shaft motor with 8mm bullet connectors and 85mm length for torque features a hardened alloy steel output shaft designed to withstand the mechanical stresses of high-speed marine use. Measuring 5mm in diameter and 21.5mm in length, the shaft provides a secure interface for propeller coupling, minimizing flex and ensuring efficient torque transfer. This robust construction is essential for maintaining alignment and preventing wear during aggressive maneuvers or heavy load conditions. The shaft’s durability contributes to the motor’s overall reliability, making it suitable for demanding applications.
Is installation straightforward for custom and RTR builds?
Ease of integration is a key consideration for RC builders, and the Spektrum P-SPMX-1075 with 2.22" diameter, 24.3 oz weight, and 21.5mm shaft length simplifies installation with 8mm bullet connectors. These connectors provide a secure and standardized interface for ESCs, reducing setup time and ensuring consistent electrical contact. The motor’s compact diameter and moderate weight allow it to fit into a wide range of hull designs without compromising balance or clearance. Whether you're upgrading an RTR platform or assembling a custom build, the motor’s dimensions and connectivity features support a hassle-free installation process.
How does the Kv rating influence speed and control?
The 740Kv brushless motor with 8.12S voltage compatibility and tight 4-pole torque delivery is optimized for high-speed performance in 12S LiPo configurations. The Kv rating determines the motor’s RPM per volt, and at 740Kv, the motor strikes a balance between rapid acceleration and manageable throttle response. This makes it suitable for both competitive racing and recreational boating, where speed and control are equally important. The motor’s voltage compatibility ensures that users can pair it with high-capacity battery systems for extended runtime and consistent output, enhancing the overall boating experience.
What makes the Spektrum P-SPMX-1075 a reliable choice for serious RC boaters?
Reliability in marine environments depends on a combination of thermal stability, mechanical strength, and electrical efficiency. The Spektrum P-SPMX-1075 brushless motor for 12S LiPo-powered high-performance RC boats delivers on all fronts. Its water-cooled housing prevents overheating, while the alloy steel shaft and precision rotor design ensure consistent torque delivery. The motor’s compact form factor and standardized connectors support easy installation, and its Kv rating is tuned for optimal speed and control. These features make the motor a dependable option for users who demand high performance without compromising durability or ease of use.
Buy Spektrum P-SPMX-1075 4685 brushless marine motor for 12S LiPo RC boat setups.
Brand, Model and Product Type
- Brand: Spektrum
- Model: P-SPMX-1075
- Product Type: Spektrum P-SPMX-1075 4685 marine motor with 740Kv rating, 4-pole design, and water-cooled housing, Spektrum P-SPMX-1075 brushless motor for 12S LiPo-powered high-performance RC boats, Spektrum P-SPMX-1075 5mm steel shaft motor with 8mm bullet connectors and 85mm length for torque, High-power marine motor for RC boats with alloy steel shaft and precision cooling system, 740Kv brushless motor with 8.12S voltage compatibility and tight 4-pole torque delivery
Dimensions
- Product Length: 8.5 cm – optimized for torque and high-power marine setups
- Product Diameter: 5.6 cm – compact form factor for streamlined hull integration
- Product Weight: 24.3 oz (690 g) – robust construction for sustained performance
Motor and Shaft Specifications
- Motor Type: Brushless – delivers high-efficiency power and low maintenance
- Motor Size: 4685 – ideal for large-scale marine propulsion
- Number of Poles: 4 – ensures tight torque delivery and smooth acceleration
- RPM/Volt (Kv): 740Kv – optimized for 12S LiPo systems and high-speed output
- Shaft Diameter: 5 mm – alloy steel for durability and torque transfer
- Shaft Length: 21.5 mm – supports secure coupling and efficient power delivery
Voltage and Compatibility
- Voltage Compatibility: 8.12S – supports high-voltage LiPo configurations
- Recommended Setup: 12S LiPo – ideal for high-performance RC boat applications
Cooling and Durability
- Cooling System: Water-cooled – maintains lower operating temperatures for sustained performance
- Construction: Alloy steel shaft and precision housing – built for marine-grade durability
Connectivity
- Connector Type: 8mm Bullet – enables secure and easy installation
Application
- Primary Use: Marine – designed for high-speed RC boats and offshore racers
What’s in the Box
- 1 × Spektrum 4685 4-Pole Brushless Marine Motor
What You Require / What You Will Need
- Compatible ESC and 12S LiPo battery system – required for full performance operation
- Water cooling loop – recommended for optimal thermal management
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.
