Replacement motor for 1.2m Warbirds excluding EFL8475/8450
Overview
The E-flite BL15 Brushless Outrunner 850kV motor (EFLM4115) is a versatile and efficient brushless motor designed specifically for RC aeroplane applications. This compact yet powerful motor delivers smooth, reliable performance in a lightweight 174-gram package, making it an ideal choice for pilots looking to upgrade or replace their existing aircraft powerplant. Whether you're flying a 1.2-metre warbird or seeking a high-quality brushless RC motor for your aircraft collection, the BL15 offers the kind of engineering excellence that E-flite is recognised for across the UK RC community.
As a replacement motor engineered for 1.2-metre warbirds (excluding EFL8475/8450 models), this brushless outrunner represents a significant step up in performance and reliability compared to brushed alternatives. The 850kV rating provides an excellent balance between speed and torque, making it suitable for a wide variety of aircraft installations and flight styles. RC enthusiasts across the UK trust E-flite brushless motors for their consistency, durability and smooth power delivery, and this BL15 model continues that tradition of quality.
If you're building or upgrading a medium-sized RC aeroplane and need a motor that combines compact dimensions with proven performance, the BL15 Brushless Outrunner is an excellent investment. The straightforward setup with included connectors and shaft adapter means you can get your aircraft airborne quickly and confidently.
Key Features
- Brushless Outrunner Design — This motor uses brushless outrunner technology, which means the rotating can surrounds stationary windings, delivering superior efficiency and longevity compared to brushed motors. Brushless motors require no brush maintenance, produce less heat, and offer significantly longer service life, making them the preferred choice for serious RC pilots.
- 850kV Rating — The 850kV constant determines the motor's RPM output relative to applied voltage, providing an optimal speed-to-torque ratio for 1.2-metre warbirds and similar aircraft. This kV rating strikes the perfect balance between raw speed and the pulling power needed for aerobatic flight and sustained cruising.
- Lightweight Compact Package — At just 174 grams, this motor adds minimal weight to your airframe, preserving the weight budget critical for optimal flight performance and battery endurance. The compact form factor means it fits easily into aircraft designs where space and mass are at a premium.
- 3.5mm Bullet Connectors — The motor comes fitted with industry-standard 3.5mm bullet connectors, ensuring compatibility with the vast majority of brushless ESCs (electronic speed controllers) available for RC aircraft. These connectors provide secure, reliable electrical contact without the need for soldering.
- 6mm Shaft with Included Adapter — The motor features a 6mm diameter adapter shaft included in the package, ensuring straightforward installation onto your aircraft's propeller and gearbox. This universal sizing works with most RC aeroplane propeller hubs and mechanical installations, reducing the need for additional adapters or modifications.
- Purpose-Built for Aeroplanes — Unlike generic motors adapted from other RC applications, the BL15 has been engineered specifically for fixed-wing aircraft, with characteristics optimised for the unique demands of aerial flight, including consistent throttle response and smooth power delivery.
Technical Performance
The E-flite BL15 Brushless Outrunner 850kV motor represents modern brushless motor engineering optimised for the RC aeroplane enthusiast. The brushless outrunner design ensures that power delivery is smooth, efficient and reliable across the entire throttle range, crucial for precision flying whether you're performing aerobatic manoeuvres or maintaining steady level flight. The 850kV rating has been specifically chosen to complement 1.2-metre warbird airframes, delivering the right combination of speed and pulling power without overwhelming either the airframe or your ESC. With a weight of just 174 grams, this motor maintains an exceptional power-to-weight ratio, allowing your aircraft to achieve excellent climb rates and sustained flight performance. The inclusion of 3.5mm bullet connectors means integration with your existing brushless ESC is straightforward and tool-free, whilst the 6mm shaft adapter provides universal compatibility with standard RC aeroplane propeller installations. Build quality is excellent throughout, with the motor's construction designed to handle the vibration and stresses inherent in powered flight. This is a motor built for reliability and longevity, backed by E-flite's reputation for quality across the UK RC community.
What's in the Box
- E-flite BL15 Brushless Outrunner motor
- 3.5mm bullet connectors
- 6mm adapter shaft
What You Need to Complete
- Brushless ESC (electronic speed controller) compatible with 3.5mm bullet connectors
- LiPo or LiPo-compatible battery pack suitable for your aircraft
- RC receiver and transmitter system
- Propeller compatible with 6mm shaft and your aircraft design
- Associated airframe and installation hardware
Frequently Asked Questions
- What aircraft is the E-flite BL15 850kV motor designed for? — The BL15 Brushless Outrunner is engineered as a replacement motor for 1.2-metre warbirds, excluding models EFL8475 and EFL8450. It's suitable for a range of medium-sized warbird and general aviation RC aeroplanes that require an 850kV brushless motor with 3.5mm connectors and 6mm shaft compatibility.
- Is this motor suitable for beginners? — Yes, the BL15 is suitable for pilots of intermediate experience and above. Whilst the motor itself is straightforward to install, operating brushless RC motors requires a compatible brushless ESC and basic understanding of LiPo battery safety. If you're new to RC flight, we'd recommend consulting with our experienced team at RC Model Shop to ensure you have all the necessary components and knowledge to fly safely.
- What connectors does this motor have? — The motor comes fitted with 3.5mm bullet connectors, which are the industry standard for RC aircraft brushless motors. These connectors are compatible with nearly all brushless ESCs designed for aircraft applications, and they can be soldered or plugged directly into your speed controller without modification.
- How much does the BL15 weigh? — The motor weighs just 174 grams (6 1/8 ounces), making it an exceptionally lightweight option ideal for 1.2-metre warbirds where every gram counts towards achieving optimal performance and battery runtime.
- What is the difference between this and brushed motors? — Brushless motors like the BL15 offer several advantages over brushed alternatives: they require no brush maintenance, produce less heat, offer significantly longer service life, deliver smoother and more efficient power, and provide better throttle response. For RC aeroplanes, brushless motors have become the standard choice due to their superior reliability and performance.
- Can I use this motor in other applications? — Whilst the BL15 is optimised for 1.2-metre warbirds and similar aircraft, the 850kV rating and compact size may suit other RC aeroplane applications. However, we recommend checking compatibility with your specific airframe and ESC before purchase.
- What ESC should I use with this motor? — The motor accepts standard RC aircraft ESCs with 3.5mm bullet connectors. The specific ESC you choose should match the voltage (2S, 3S, 4S LiPo etc.) and current rating appropriate for your aircraft and flying style. Our team at RC Model Shop can help you select the right ESC for your setup.
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 E-flite BL15 Brushless Outrunner 850kV M-EFLM4115 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.
- 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.
