HOBBYWING COMBO XR10 JUSTOCK G3S ESC/JUSTOCK G2.1 13.5T (Fixed Timing) HW38020371

Overview

The Hobbywing XeRun XR10 Justock G3S ESC paired with the G2.1 13.5T fixed-timing brushless motor represents a complete and sophisticated solution for competitive 1/10 and 1/12 scale RC racing in the United Kingdom and worldwide. This HW38020371 combo is specifically engineered for zero-timing (blinky) competition formats, delivering the precision control and powerful performance that serious racers demand. Whether you're competing at club level on-road or off-road tracks, or training for higher-level championships, this combo provides the reliability and advanced features needed to maximise your RC car's potential.

For UK RC enthusiasts looking for a high-performance ESC and motor combo that combines competition-grade engineering with user-friendly programming, the Hobbywing Justock combo stands out as a trusted choice. The XR10 G3S speed controller is not just a simple power controller—it's a fully-featured electronic brain that monitors your vehicle's performance in real-time, adapts to changing conditions, and gives you access to detailed telemetry data through wireless connectivity. When paired with the G2.1 motor's smooth, linear power delivery and durable construction, you get a system that will serve you reliably through season after season of competitive use.

This is more than just a replacement ESC and motor; it's an investment in competitive success. Hobbywing's engineering reputation, combined with the advanced features packed into the G3S controller, makes this an ideal choice for racers who refuse to compromise on performance or reliability.

Key Features

• XR10 Justock G3S Speed Controller — The ESC at the heart of this combo is purpose-built for zero-timing (blinky) format racing, with parameters specifically optimised to meet the needs of competitive racers worldwide who require precise throttle control and responsive handling characteristics.
• Intelligent Fan Control with Automatic Start/Stop — Rather than running continuously and consuming unnecessary power, the ESC's intelligent fan only activates when the controller reaches a preset temperature threshold, reducing noise, saving battery energy, and ensuring the ESC operates within optimal temperature ranges for reliability and longevity.
• Freewheeling Function for Enhanced Cornering — When enabled, the freewheeling feature allows the motor to disconnect from the drivetrain when throttle is released, resulting in lower ESC temperatures, faster vehicle deceleration when you lift off the throttle, and significantly improved controllability through corners—a crucial advantage in competitive racing.
• Built-in Polarity Protection — This essential safety feature protects the entire electrical system from potential damage caused by reversed battery polarity, which can occur from accidental terminal reversal or short circuits, giving you peace of mind during setup and operation.
• Multi-Position RPM Limiting with 79 Selectable Values — Supporting RPM limits from 10,000 to 88,000 RPM with 79 individual selectable values, the XR10 G3S allows you to adjust performance to meet specific competition regulations or track conditions, whether using the LCD Program Box Pro or the wireless OTA Bluetooth module for convenient programming.
• Integrated Capacitor Module with Optimised Layout — The built-in capacitor module eliminates the need for external capacitors, reducing wiring complexity, saving valuable space on your vehicle, and improving overall reliability by using Hobbywing's proven capacitor design integrated directly into the ESC.
• Powerful Built-in BEC (Battery Elimination Circuit) — With a maximum output of 8A, the BEC can power even modern high-torque servos reliably, with selectable output voltage of either 6V or 7.4V to match your servo requirements and ensure consistent servo performance throughout your run.
• Comprehensive Data Logging and Analysis — The ESC records critical performance data including minimum voltage, maximum ESC temperature, maximum current draw, maximum motor temperature, and maximum RPM, allowing you to review your vehicle's performance after each run and identify optimisation opportunities.
• Wireless Data Recording via OTA Bluetooth Module — By connecting the optional OTA Bluetooth module and using the HW Link mobile app, you gain real-time access to throttle position, voltage, current, temperature, and speed data with an effective range of approximately 5 metres, enabling live telemetry monitoring and detailed historical data analysis with graphical trends.
• Sensored Hall Effect Motor System — The G2.1 13.5T motor features a built-in Hall sensor that works seamlessly with the XR10 G3S ESC, providing smooth, linear power delivery and reliable commutation at all throttle positions, essential for the precise control demanded in competitive zero-timing racing.
• Heat-Resistant Magnet with Aluminium Case — The motor housing is constructed from aluminium with a heat-resistant magnet assembly, and incorporates double-insulated windings and high-precision bearings that guarantee outstanding performance and exceptional durability under the demands of competitive club racing.
• Silicon O-Ring Seal with Thermal Management — The silicon O-ring seal between the end bell and stator serves dual purposes: conducting internal motor heat outward to the aluminium case for improved thermal dissipation, whilst simultaneously preventing dust and debris from entering the Hall sensor cavity, extending service life and maintaining reliability.
• Detachable Structure for Easy Maintenance — The motor's modular design allows straightforward disassembly for routine cleaning and maintenance, enabling you to remove carbon deposits and check bearing condition easily, which directly extends service life and improves operating efficiency over the long term.
• IFMAR and ROAR Compliant Design — Both the ESC and motor are engineered in compliance with International Federation of Model Auto Racing (IFMAR) and Radio Operated Auto Racing (ROAR) specifications, ensuring they meet international competition standards and can be used at recognised racing events worldwide.
• Firmware Upgrade Capability — The ESC supports firmware updates, ensuring that Hobbywing can provide performance improvements, new features, and bug fixes throughout the product's lifespan, keeping your controller current with the latest technological advances.

Technical Performance

The XeRun XR10 Justock G3S delivers genuine competition-grade performance through its 60-amp continuous current rating and 380-amp peak capacity, handling the demanding power draws of modern brushless 13.5-turn motors without hesitation. The controller operates on a single 2S LiPo battery pack (7.4V nominal), making it suitable for both on-road and off-road 1/10 and 1/12 scale racing platforms. The compact dimensions of just 40.9 × 33.9 × 32.1 millimetres and lightweight design of approximately 75.4 grammes with pre-installed wiring keep your vehicle's centre of gravity low and weight distribution optimal—critical factors in competitive handling. The G2.1 13.5-turn fixed-timing motor, rated for a minimum 10.5-turn or 3650 KV compatibility standard, is built around a 540-size brushless platform using precision-machined components and high-grade bearings to deliver smooth, responsive power characteristics. The motor's heat-resistant magnet assembly and thermal management system ensure sustained performance throughout extended run sessions. With the intelligent fan control reducing unnecessary power consumption, the entire combo operates efficiently, extending your runtime per charge whilst maintaining cooler operating temperatures. The brushless sensored design guarantees linear throttle response from zero to full throttle, essential for the precise control required in modern competitive racing. When combined with the comprehensive data logging capabilities, you gain complete visibility into your vehicle's performance parameters, allowing data-driven tuning decisions that can provide real competitive advantages on the track.

What's in the Box

• XeRun XR10 Justock G3S Speed Controller with pre-installed 14AWG black and red input wires (200mm length)
• G2.1 13.5T fixed-timing brushless motor with Hall sensor
• Three black 14AWG output wires (200mm length) for motor and servo connections
• Quick-start documentation and reference guide

What You Need to Complete

• Single 2S LiPo battery pack (7.4V) with appropriate connector
• LiPo battery charger compatible with 2S packs
• Servo for steering control
• Radio receiver compatible with your transmitter
• Your choice of vehicle chassis (1/10 or 1/12 on-road or off-road)
• Optional: LCD Program Box Pro or OTA Programmer for programming the ESC beyond basic throttle calibration
• Optional: HW Link mobile app and OTA Bluetooth module for wireless data logging and real-time telemetry (effective range approximately 5 metres)
• Optional connector upgrades available, including Deans connectors, 3.5mm, 4mm, or 5mm bullet connectors for ESC and motor wires

Frequently Asked Questions

• Is the Hobbywing Justock G3S ESC legal for BRCA Nationals competition? — The XR10 Justock G3S is suitable for zero-timing (blinky) format racing at club level competitions. However, it is not BRCA legal for the 2024 Nationals in the 17.5T or FWD class. If you're competing at BRCA National level in those specific classes, alternative controllers such as the HW30112003, HW38020321, or HW30408011 would be required.
• Can this combo work with batteries other than 2S LiPo? — No. The XR10 Justock G3S is designed specifically for 2S LiPo battery packs (7.4V nominal). The voltage range supported is 5.0V to 7.4V, which covers the operating window of a properly maintained 2S LiPo. Using batteries outside this specification will damage the ESC and void the warranty.
• What is the difference between the Justock G3S and earlier Justock models? — The G3S (Generation 3S) represents the latest technology in the Justock family, incorporating improved parameters specifically tailored to meet modern competition needs, enhanced firmware, upgraded fan control logic, and better thermal management compared to earlier generations. The G3S also supports more advanced programming options and offers superior real-time data logging capabilities.
• Is this suitable for racing beginners or only experienced competitors? — Whilst the XR10 Justock G3S is competition-grade hardware designed for demanding club-level racing, beginners can certainly use it successfully. The ESC is user-friendly with simple throttle calibration via the SET button on the board itself. However, to unlock advanced features like RPM limiting and fine-tuning parameters, you would benefit from the optional LCD Program Box Pro. The included quick-start guide provides straightforward setup instructions for first-time users.
• What servo power rating should I use with this ESC? — The integrated BEC supplies up to 8 amperes at either 6V or 7.4V output, sufficient to power virtually all modern high-torque racing servos used in 1/10 and 1/12 scale vehicles. Servos rated for these voltage ranges and drawing less than 8 amperes during operation will function reliably. Verify your servo's current draw specifications to ensure compatibility.
• Can I use this ESC with motors other than the included G2.1 13.5T? — Yes, the XR10 Justock G3S is compatible with other Hobbywing sensored brushless motors and many other quality sensored brushless motors from different manufacturers, provided they meet the minimum rating of 10.5T or higher and operate on sensored (Hall effect) commutation. The ESC is engineered to work specifically well with Hobbywing's Justock motor range and other Hobbywing products in the XeRun series.
• How do I programme the RPM limits for specific racing formats? — You can programme the 79 selectable RPM limits (10,000 to 88,000 RPM) using either the optional LCD Program Box Pro connected via the separate program port, or wirelessly through the OTA Programmer module connected to your smartphone via the HW Link app. The SET button on the ESC itself allows basic calibration but not detailed RPM programming.
• What does the data logging feature actually show me? — The built-in data logging captures extreme values (minimum voltage, maximum temperature, maximum current, maximum motor temperature, and maximum RPM) from each run. When paired with the OTA Bluetooth module and HW Link app, you gain real-time monitoring of throttle input, voltage, current, ESC temperature, motor temperature, and speed, with historical data graphing capabilities to analyse performance trends across multiple runs.
• Is the motor waterproof for off-road muddy conditions? — The G2.1 motor is not rated as waterproof. Whilst the detachable end bell and silicon O-ring seal provide some dust and water resistance during normal off-road use, the motor is not sealed against submersion. The ESC is similarly not waterproofed. If running in extremely wet conditions, take precautions to protect these components from water ingress.
• Can I connect the wireless OTA module outdoors at racing events? — The OTA Programmer module supports Bluetooth 4.0 or later with an effective range of approximately 5 metres in open field conditions. At crowded racing events with multiple wireless devices, interference may reduce this range. It's designed for trackside telemetry monitoring and data review but should not be relied upon for wireless control of the vehicle itself.

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 HOBBYWING COMBO XR10 JUSTOCK G3S ESC/JUSTOCK G2.1 13.5T (Fixed Timing) HW38020371 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.