Overview

The Futaba HPS-CB701 Standard Brushless Servo MG PWM/S.BUS2 represents the pinnacle of high-performance servo technology for demanding RC car applications. Whether you're piloting a competitive 1/10 scale on-road or off-road racer, or tackling the more aggressive terrain with a 1/8 scale machine, this programmable brushless servo delivers the precision, speed and holding power required to dominate on the track or bash field. As an authorised Futaba retailer, RC Model Shop supplies this genuine HPS-CB701 servo to RC enthusiasts across the UK who demand nothing but the best from their equipment.

Built around a custom high-power brushless motor and housed in a robust full-aluminium case, the HPS-CB701 combines rapid response times with exceptional torque output in a compact standard-size package. This servo is engineered for racers and serious RC car UK hobbyists who require programmable functionality, low-latency performance modes and compatibility with modern digital radio systems. The HPS-CB701 isn't just another servo—it's a precision instrument designed to translate your steering and throttle inputs into immediate, accurate mechanical response.

What truly sets this brushless servo apart is its versatility and future-proofing. Full compatibility with Futaba's S.BUS and S.BUS2 digital protocols means you can integrate it seamlessly into modern radio systems, whilst support for both SR (slow response) and UR (ultra-response) modes gives you the flexibility to tune performance characteristics to match your driving style and vehicle setup. For ready to run RC car enthusiasts in the UK looking to upgrade their steering servo, the HPS-CB701 is an investment in reliability, speed and control.

Key Features

• Custom high-power brushless motor — The brushless design eliminates carbon brush wear and maintenance, delivering consistent performance across thousands of operating cycles whilst generating smooth, powerful movement that makes this ideal for racing applications where every millisecond counts.
• Exceptional speed rating of 0.075 seconds at 7.4V — At maximum voltage, this servo executes a full 60-degree rotation in just 0.075 seconds, providing the lightning-fast steering response required for competitive on-road and off-road RC car racing in the UK.
• Massive 49 kgf/cm torque output at 7.4V — With 680.5 ounces-force per inch of torque available, the HPS-CB701 holds position with absolute confidence even under aggressive steering loads, making it perfect for high-speed cornering and demanding off-road obstacles.
• Full aluminium case construction — The upper, middle and bottom case panels are machined from aluminium alloy, providing superior strength, excellent heat dissipation to keep the servo running cool during extended racing sessions, and enhanced durability that withstands the rigours of competitive and casual RC car use.
• Metal gear train (MG) — The entire internal gear system uses metal construction, with a robust 1-3 gear train and reinforced final gear to handle the high torque loads generated by the brushless motor without stripping or slipping.
• Dual ball bearing motor support — Precision ball bearings support the brushless motor shaft, reducing friction and ensuring smooth, efficient operation with minimal mechanical noise and maximum responsiveness.
• S.BUS2, S.BUS and PWM command protocol support — This servo speaks multiple languages, making it compatible with legacy PWM radio systems as well as modern digital S.BUS and S.BUS2 setups from Futaba, ensuring broad compatibility across different control systems.
• Programmable via CIU-2/-3 USB adapter — Connect to a computer and fine-tune servo behaviour including centre point adjustment, speed curves and end-point programming using the Futaba software ecosystem (adapter sold separately).
• SR mode support with T4PM/P, T7PX/R and T10PX transmitters — For owners of compatible Futaba radio systems, SR mode unlocks low-latency performance with reduced command delay, giving you a more connected feel during racing.
• UR mode support with T10PX transmitter — The flagship UR (ultra-response) mode available with the T10PX delivers the absolute fastest command processing, perfect for precision steering at race speeds.
• Standard-size form factor — At just 40.5 × 21.0 × 37.8 millimetres and weighing only 75 grams, this servo fits cleanly into standard servo bays on 1/10 and 1/8 scale RC cars without modification or custom mounting solutions.
• Wide voltage operating range — The rated voltage specification of 6.0V to 7.4V can be extended to the operating range of 4.8V to 8.4V, giving you flexibility with different battery pack configurations and the ability to boost performance with higher-voltage LiPo setups.
• 25T spline with 6mm diameter shaft — The industry-standard spline accepts a wide range of aftermarket servo horns available for RC cars in the UK, allowing you to customise the servo arm length and throw distance to suit your specific vehicle setup.

Technical Performance

The HPS-CB701 represents a significant engineering achievement in brushless servo technology. At its core sits a custom-designed brushless motor that eliminates the carbon brushes found in conventional servos, resulting in cooler operation, longer lifespan and more consistent performance across the full voltage range. The brushless design is particularly advantageous for RC car applications where heat management and reliability are paramount—during extended racing or bashing sessions, brush friction generates heat that can degrade servo components, whilst the brushless motor's inherent efficiency keeps operating temperatures lower.

Performance specifications are exceptional across the board. At the rated 6.0V, the HPS-CB701 delivers 42.0 kgf/cm of torque and completes a 60-degree rotation in 0.09 seconds. Step up to the maximum rated voltage of 7.4V—achievable with a modern LiPo battery pack, the standard in competitive RC car UK racing—and performance jumps dramatically: 49.0 kgf/cm of torque and 0.075-second response time. This speed improvement is meaningful for steering servo applications, where shaving milliseconds off your input response directly translates to better line accuracy through corners. The torque figures translate to 583.3 and 680.5 ounces-force per inch respectively, providing the holding power needed to maintain precise steering angle against aerodynamic forces at speed or the massive forces generated when powering through deep ruts and obstacles on off-road courses.

Build quality is exemplary. The full-aluminium case isn't merely cosmetic—it serves critical functions in thermal management and structural rigidity. Aluminium's excellent thermal conductivity means heat generated by the motor and gears dissipates rapidly to the surrounding air, preventing the performance degradation that occurs when servos overheat. The one-piece aluminium construction also eliminates flexing in the servo case, which can introduce play in the output shaft and reduce steering precision. Internally, the metal gear train uses a 1-3 gear reduction system with a reinforced final gear specifically engineered to transmit the high torque of the brushless motor without slipping or stripping. The dual ball bearings supporting the motor shaft minimise friction and ensure the brushless motor spins with maximum efficiency, whilst the metal gears ensure durability even under the peak torque conditions encountered during aggressive racing or high-load off-road applications.

Compatibility across radio protocols is comprehensive. The HPS-CB701 works with traditional PWM (Pulse Width Modulation) signals from older radio systems, the intermediate S.BUS digital protocol, and the latest S.BUS2 standard which incorporates telemetry feedback and additional programming channels. This multi-protocol approach means you can integrate the HPS-CB701 into your existing setup regardless of whether you're running legacy equipment or modern digital radio gear. Owners of Futaba's advanced transmitters—the T4PM/P, T7PX/R and T10PX—unlock additional performance through SR and UR modes. SR mode reduces command latency for a more responsive feel, whilst UR mode provides ultra-low latency ideal for precision steering at racing speeds where every microsecond of delay can affect lap times and line consistency.

The operating voltage range deserves specific attention for RC car enthusiasts planning upgrades. Whilst the rated specification is 6.0V to 7.4V, the actual operating range extends to 4.8V minimum and 8.4V maximum. This flexibility is valuable—at 4.8V you can run the servo on older 4-cell NiMH packs if needed, whilst many RC racers routinely run 2S LiPo packs (7.4V nominal, 8.4V when freshly charged) to access the maximum performance figures. Some competitors even experiment with higher-voltage packs to extend the upper range, though this should be done with understanding of the trade-offs involved. The servo ships with servo horns and mounting hardware included, meaning you can install it immediately into any RC car with a compatible servo bay.

What's in the Box

• 1× Futaba HPS-CB701 Standard Brushless Servo
• Servo horns (plastic arms for connecting to steering linkages)
• Mounting hardware (screws and brackets for installation)

What You Need to Complete

• RC car or truck with compatible standard servo bay (1/10 or 1/8 scale recommended)
• Radio transmitter and receiver system compatible with PWM, S.BUS or S.BUS2 protocols
• Battery pack rated for your vehicle (2S LiPo or equivalent voltage)
• Servo horns compatible with 25T 6mm spline (included with servo, or aftermarket options available)
• CIU-2 or CIU-3 USB adapter if you intend to program the servo via computer (sold separately)

Frequently Asked Questions

• What voltage battery should I use with the Futaba HPS-CB701 servo? — The servo is rated for 6.0V to 7.4V operation. Most RC car racers in the UK use a 2S LiPo battery pack, which provides approximately 7.4V nominal voltage (8.4V when fully charged). This voltage range maximises the servo's performance specifications. You can operate at lower voltages down to 4.8V if necessary, though torque and speed will be reduced. Do not exceed 8.4V even for brief periods, as this exceeds the maximum operating voltage.
• Is the HPS-CB701 suitable for 1/10 and 1/8 scale RC cars? — Yes, the HPS-CB701 is specifically designed for 1/10 scale on-road and off-road RC cars, as well as 1/8 scale on-road and off-road applications. The standard servo size fits directly into OEM servo bays on most vehicles in these scales. Futaba explicitly states this servo should only be used on RC cars smaller than 1/5 scale.
• What is the difference between PWM, S.BUS and S.BUS2 protocols? — PWM (Pulse Width Modulation) is the original servo control protocol, using a single wire to transmit servo position information. S.BUS is a digital protocol developed by Futaba that carries multiple channel commands over a single wire, reducing wiring complexity. S.BUS2 extends S.BUS with bidirectional communication, allowing the servo to send telemetry data back to the transmitter. The HPS-CB701 supports all three protocols, making it compatible with virtually any Futaba radio system.
• Can I program the HPS-CB701 servo? — Yes, the HPS-CB701 is fully programmable. You can adjust centre point, speed curves, endpoint programming and other parameters. Programming is accessed via an optional CIU-2 or CIU-3 USB adapter (sold separately) which connects the servo to a computer running Futaba's programming software. Additionally, if your transmitter supports SR or UR modes (T4PM/P, T7PX/R, or T10PX), you can access some programming functions directly through the radio menu without a computer.
• What makes the brushless motor better than a traditional brushed servo motor? — Brushless motors eliminate carbon brushes, which wear out over time and generate heat through friction. The brushless design runs cooler, lasts longer, and delivers more consistent torque throughout the motor's life. For RC car racing where reliability and consistent performance are critical, brushless technology is the modern standard.
• What is SR mode and UR mode? — SR (slow response) and UR (ultra-response) are performance modes available on compatible Futaba transmitters. SR mode reduces response latency for a more connected feel during racing, whilst UR mode provides ultra-low latency command processing, typically used by competitive drivers who demand absolute maximum responsiveness. Both modes require compatible transmitters (T4PM/P, T7PX/R, or T10PX for UR).
• Is this servo waterproof? — The manufacturer specifications do not indicate an IP waterproof rating for the HPS-CB701. Whilst the aluminium case provides some weather resistance and the servo will tolerate occasional light moisture exposure during outdoor RC car use, it should not be submerged or exposed to heavy water spray. For truly waterproof servo applications, dedicated waterproof servo models are available.
• What is the difference between the HPS-CB701 and other Futaba servo models? — The HPS-CB701 is part of Futaba's high-performance HPS servo series, specifically engineered for brushless motor technology. It represents a performance tier above standard servos, with faster response times, higher torque output and programmable features. The aluminium case and metal gears also distinguish it from budget servo models. If you need maximum performance for competitive racing or demanding off-road use, the HPS-CB701 is an excellent choice.
• What spline size does the HPS-CB701 use? — The HPS-CB701 features a 25-tooth (25T) spline with a 6mm shaft diameter, which is the industry-standard spline used on most modern RC car servos. This ensures compatibility with a vast array of aftermarket servo horns available from UK RC retailers, allowing you to customise servo arm length and throw distance to match your specific vehicle setup.
• How much does the HPS-CB701 weigh? — The servo weighs just 75 grams (2.65 ounces), making it lightweight enough for 1/10 and 1/8 scale applications where servo weight affects vehicle handling balance and suspension compliance. Despite the light weight, the metal gears and aluminium case provide the structural strength needed for high-performance racing.

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 Futaba HPS-CB701 Standard Brushless Servo MG PWM/S.BUS2 49kg 0.075s 4.8V - 7.4V FUT05102698-3 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.