- Product type: Suspension hinge pin (lower)
- Quantity: 2 hinge pins per package
- Diameter: 4mm
- Length: 63.5mm
- Material: Steel
- Finish: Polished
- Manufacturer: ARRMA
- Model number: ARA330731
- Part number: Z-ARA330731
- EAN: 5052127039468
- Spare part category: Suspension
- Required component: ARA320658 - Lower Arm Adjustment Block Set
- Required suspension mounts: Either ARA320652 and ARA320653 OR ARA320655 and ARA320656
- Compatible with: ARRMA 1/10 BIG ROCK 223S, ARRMA 1/10 KRATON 4S, ARRMA 1/10 OUTCAST 4S, ARRMA 1/7 BIG ROCK 6S, ARRMA 1/7 FIRETEAM 6S, ARRMA 1/8 KRATON 6S, ARRMA 1/8 MOJAVE 4S, ARRMA 1/8 NOTORIOUS 6S, ARRMA 1/8 OUTCAST 6S, ARRMA 1/8 TALION 6S, ARRMA 1/8 TYPHON 223S, ARRMA 1/8 TYPHON 6S, ARRMA 1/8 TYPHON 6S TLR Tuned, ARRMA 1/8 TYPHON MEGA 665
Overview
These tough steel hinge pins are the perfect spare part for your RC tool box and an essential maintenance item for serious RC enthusiasts in the UK. Whether you're running an ARRMA 1/8 scale brushless speed truck, buggy, or monster truck, having replacement hinge pins on hand ensures you can keep your suspension in peak condition and maintain smooth, responsive handling on the track or bash course. The ARRMA Hinge Pin Lower 4x63.5mm (2) is specifically engineered as a suspension component that directly affects how your ready to run RC car performs during high-speed runs and aggressive cornering.
Hinge pins are critical suspension components that allow your RC car's lower control arms to move smoothly through their full range of motion. Over time, standard hinge pins can wear, bend, or develop flat spots from intense bashing, racing, or track use, which degrades suspension geometry and handling precision. This is why keeping quality replacement hinge pins in your spares box is essential for maintaining consistent performance. ARRMA has engineered these hinge pins from strong steel material to withstand the demands of brushless RC vehicles, ensuring they maintain their shape and smoothness through countless suspension cycles.
The polished finish on these hinge pins is not merely aesthetic—it's a functional feature that reduces friction and ensures silky-smooth suspension action. When your suspension moves freely without binding or resistance, your RC car responds more predictably to steering inputs, absorbs bumps and jumps more effectively, and maintains better traction. This translates to faster lap times for racers and more enjoyable bash sessions for weekend drivers. Whether you're competing in UK RC clubs or just enjoying your brushless RC truck for leisure, having access to genuine ARRMA replacement parts means you can maintain your vehicle in factory condition.
Key Features
- Strong steel material — These hinge pins are manufactured from quality steel that resists bending and deformation under the high loads experienced during acceleration, braking, and cornering in 1/8 scale brushless RC vehicles. Steel's superior strength compared to alternative materials ensures long-lasting durability and consistent performance through hundreds of suspension cycles.
- 4mm diameter with 63.5mm length — The precise dimensions of these hinge pins (4 x 63.5mm) are engineered to match the original ARRMA specification, ensuring perfect fitment in your suspension mounting points and maintaining correct suspension geometry for optimal handling and stability.
- Polished finish for smooth suspension action — The polished surface treatment reduces friction between the hinge pin and the suspension arm bushings, eliminating binding and ensuring your suspension moves freely with minimal resistance. This results in more responsive steering, better shock absorption, and improved overall handling characteristics.
- Pair of two hinge pins — Each package contains two hinge pins, allowing you to replace both lower hinge pins simultaneously or keep one as a spare for future maintenance. This ensures symmetrical suspension geometry on both sides of your RC car.
- Genuine ARRMA OEM part — These are official ARRMA replacement parts engineered to original specifications, guaranteeing compatibility and performance with your ARRMA ready to run RC vehicle.
Technical Performance
The ARRMA Hinge Pin Lower is engineered with meticulous attention to detail for high-performance RC vehicles. At 4mm in diameter and 63.5mm in length, these hinge pins are precisely sized to work within ARRMA's suspension architecture, which includes lower arm adjustment blocks and adjustable suspension mounts. The steel construction provides the rigidity necessary to maintain suspension geometry under the extreme forces generated by brushless motors and high-speed running. The polished finish is critical for performance—it minimises friction at the contact points where the hinge pin interfaces with the suspension arm bushings, allowing the suspension to articulate smoothly without resistance that would otherwise reduce responsiveness and increase wear. This is particularly important in 1/8 scale brushless RC vehicles that demand precise handling and consistent performance. The hinge pins work in conjunction with ARRMA's lower arm adjustment block set (ARA320658) and adjustable suspension mounts to create a tunable, reliable suspension system that can be dialled in for different track conditions, driving styles, and terrains. Whether you're running your ARRMA brushless RC truck on a groomed race track, rocky terrain, or for general bashing, these hinge pins help maintain the suspension's ability to absorb impacts and maintain traction.
What's in the Box
- 2 x Hinge Pin Lower - 4 x 63.5mm
What You Need to Complete
- ARA320658 - Lower Arm Adjustment Block Set (required)
- Either ARA320652 - Aluminium Adjustable Front Front Suspension Mount (TLR) and ARA320653 - Aluminium Adjustable Front Rear Suspension Mount (TLR), OR ARA320655 - Aluminium Adjustable Rear Front Suspension Mount (TLR) and ARA320656 - Aluminium Adjustable Rear Rear Suspension Mount (TLR)
- Compatible ARRMA RC model (see compatibility list below)
Compatibility
The ARRMA Hinge Pin Lower 4x63.5mm is a standard suspension component compatible with the following ARRMA ready to run RC vehicles: 1/10 BIG ROCK 223S 4X4 RTR Brushless Monster Truck (ARA4312V4), 1/10 KRATON 4S 4X4 RTR Brushless Speed Truck (ARA4408V2), 1/10 OUTCAST 4S 4X4 RTR Brushless Stunt Truck (ARA4410V2), 1/7 BIG ROCK 6S 4X4 RTR Brushless Monster Truck (ARA7612), 1/7 FIRETEAM 6S 4X4 RTR Brushless Buggy (ARA7618), 1/8 KRATON 6S 4X4 RTR Brushless Speed Truck (ARA106040 and ARA8608V5), 1/8 MOJAVE 4S 4X4 RTR Brushless Desert Truck (ARA4404), 1/8 NOTORIOUS 6S 4X4 RTR Brushless Stunt Truck (ARA106044 and ARA8611V5), 1/8 OUTCAST 6S 4X4 RTR Brushless Stunt Truck (ARA106042), 1/8 TALION 6S 4X4 RTR Brushless Speed Truck (ARA106048), 1/8 TYPHON 223S 4X4 RTR Brushless Buggy (ARA4306V4), 1/8 TYPHON 6S 4X4 RTR Brushless Buggy (ARA106046 and ARA8606V5), 1/8 TYPHON 6S TLR Tuned 4X4 Roller Brushless Buggy (ARA8306), 1/8 TYPHON MEGA 665 4X4 RTR Brushed Buggy (ARA4206V4), and 1/8 TYPHON 6S TLR Tuned 4X4 RTR Brushless Buggy (ARA8406).
Frequently Asked Questions
- What are hinge pins and why do I need replacement hinge pins for my ARRMA RC car? — Hinge pins are suspension components that form the pivot point between your lower control arms and the main chassis. They allow smooth vertical suspension movement essential for handling bumps and maintaining traction. Over time, particularly with intensive racing or bashing, hinge pins can wear, bend, or develop flat spots that degrade suspension performance and handling. Keeping replacement hinge pins in your spares box ensures you can maintain your RC car in peak condition and restore original suspension geometry whenever needed.
- Are these genuine ARRMA parts? — Yes, these are official ARRMA OEM (original equipment manufacturer) replacement parts engineered to exact ARRMA specifications. Genuine parts ensure perfect compatibility with your ARRMA ready to run vehicle and maintain factory performance standards. Using genuine ARRMA suspension components is particularly important because suspension geometry directly affects handling, stability, and longevity of your RC car.
- Do these hinge pins work with all ARRMA models? — These hinge pins are compatible with a wide range of ARRMA vehicles including 1/10 and 1/8 scale brushless speed trucks, buggies, stunt trucks, and monster trucks. However, they are specifically designed for models that use the lower arm adjustment block set (ARA320658) and the associated adjustable suspension mounts. Always verify your specific ARRMA model in the compatibility list before purchasing.
- What makes the polished finish important? — The polished finish reduces friction at the contact points between the hinge pin and suspension arm bushings, allowing your suspension to articulate smoothly without binding or resistance. This is critical for maintaining responsive steering, consistent handling, and preventing premature wear on suspension components. A polished, friction-free hinge pin allows your brushless RC truck or buggy to respond instantly to steering inputs and absorb impacts more effectively.
- How long do hinge pins typically last? — The lifespan of hinge pins depends on driving intensity, terrain, and maintenance. High-speed racing, aggressive bashing on rocky terrain, and jumping put more stress on hinge pins than casual running. Regular inspection of your suspension components and replacement when wear becomes visible ensures your RC car maintains consistent handling and prevents suspension damage.
- Can I use non-ARRMA hinge pins as replacements? — While aftermarket alternatives may be available, using genuine ARRMA parts ensures perfect fitment, material quality, and suspension geometry. Suspension is critical to your RC car's performance and longevity, making genuine replacement parts a worthwhile investment for serious UK RC enthusiasts.
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 ARRMA Hinge Pin Lower 4x63.5mm (2) Z-ARA330731 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.
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