Overview
The ARRMA Shock Springs 130mm 2.21N-mm (12.62lb/in) represent an essential upgrade and maintenance component for owners of high-performance ARRMA RC vehicles, particularly the popular 1/5 scale Kraton and Outcast 8S models. These precision-engineered suspension springs allow you to fine-tune your RC car's handling characteristics in seconds, making them indispensable for both casual bashers and competitive RC enthusiasts in the UK. Whether you're looking to improve your vehicle's ride quality over rough terrain or optimise suspension geometry for specific track conditions, replacement shock springs are a crucial part of ongoing RC vehicle maintenance.
Shock springs are fundamental to any RC suspension system, and having quality replacements on hand ensures your brushless RC truck maintains optimal performance throughout the season. The ARRMA brand has built a reputation for manufacturing durable, reliable components that stand up to the demands of high-speed off-road driving, and these shock springs are no exception. They're manufactured to exacting standards from premium spring steel, ensuring consistent performance and long-lasting durability that serious RC enthusiasts have come to expect from ARRMA products.
These springs are not just replacement parts—they're tuning tools that give you direct control over your vehicle's suspension stiffness and overall handling balance. By selecting the correct spring rate for your driving style, weight distribution, and terrain, you can dramatically improve traction, stability, and cornering performance. For those serious about getting the most from their 1/5 scale RC trucks, understanding and investing in quality shock springs is a mark of a committed hobbyist.
Key Features
- Precision Spring Steel Construction — These shock springs are precision manufactured from high-quality spring steel, which provides consistent performance and long-lasting durability through hundreds of hours of driving. Spring steel maintains its properties even under repeated compression and extension cycles, ensuring reliable performance season after season, which is critical for RC cars that experience constant suspension articulation.
- Optimised 130mm Length — The 130mm length is specifically engineered to fit ARRMA 1/5 scale models including the Kraton 8S and Outcast 8S trucks, ensuring perfect compatibility and proper suspension geometry. This length works in harmony with your vehicle's shock absorber travel to deliver the correct damping characteristics and ride height.
- Measured Spring Rate of 2.21N/mm — With a spring rate of 2.21 Newtons per millimetre (equivalent to 12.62 pounds per inch), these springs provide a moderate stiffness that balances responsiveness with comfort, making them suitable for a variety of driving conditions from loose dirt to packed surfaces. This particular rate is a standard specification designed to work with ARRMA's suspension geometry and shock absorber tuning.
- Dual Pack Format — The package includes two shock springs, which is the standard requirement for the rear suspension of most ARRMA trucks where both rear shocks need matching springs. Having a pair ensures symmetrical suspension behaviour and balanced handling across both sides of your RC vehicle.
- Easy Installation and Tuning — Shock springs can be changed quickly without requiring specialist tools or extensive disassembly, allowing you to experiment with different spring rates and find the optimal setup for your driving style and local terrain. This tunability is one of the great advantages of owning a quality RC truck in the UK hobbyist community.
Technical Performance
These ARRMA shock springs deliver consistent, predictable suspension performance through their precise engineering and quality materials. The 2.21N/mm spring rate (12.62lb/in) has been carefully selected to provide the right balance between suspension compliance and control for 1/5 scale brushless RC trucks. The springs work in conjunction with ARRMA's shock absorbers to manage suspension travel, absorb impacts from jumps and rough terrain, and maintain consistent ride height under acceleration and braking. The 130mm length ensures proper shock stroke and allows the suspension to articulate through its full range of motion without bottoming out or topping out. The precision manufacturing process ensures that each spring in the pair matches perfectly, eliminating any side-to-side imbalance that could cause handling inconsistencies. Spring steel construction means these components will maintain their elastic properties even after thousands of compression cycles, resisting permanent deformation that can occur with inferior materials. For RC enthusiasts in the UK running their ARRMA Kraton 8S or Outcast 8S at high speeds across variable terrain, these springs provide the reliability and performance needed to stay competitive or simply enjoy maximum fun on the bash spot.
What's in the Box
- 2 x Shock Springs, 130mm length, 2.21N/mm (12.62lb/in) spring rate
Frequently Asked Questions
- Which ARRMA models are compatible with these 130mm shock springs? — These springs are specifically designed for ARRMA 1/5 scale trucks including the Kraton 8S (including the RTR and EXB variants) and the Outcast 8S (RTR and EXB variants). They function as both standard replacement parts for these models and optional tuning components for enthusiasts looking to adjust suspension characteristics.
- How often should I replace my RC shock springs? — Shock springs should be replaced when they lose their spring rate, become permanently compressed, or if you notice your vehicle's ride height has changed. For regular bashers, this might be every season or two, whilst racing enthusiasts might replace them more frequently. It's good practice to keep spare springs on hand for your RC truck collection.
- What is the difference between 2.21N/mm and other spring rates? — The spring rate (measured in Newtons per millimetre or pounds per inch) indicates how stiff the spring is. A lower rate (softer spring) allows more suspension travel and provides better compliance over rough terrain, whilst a higher rate (stiffer spring) reduces body roll and provides more immediate steering response. The 2.21N/mm rate is a moderate specification suitable for general-purpose driving.
- Can I use different spring rates on different shocks? — Whilst technically possible, it's not recommended as it will cause uneven suspension characteristics and handling imbalance. For optimal performance, always use matching pairs of springs on both rear shocks, and ensure they're the same spring rate specified for your vehicle.
- Are these genuine ARRMA parts? — Yes, these are authentic ARRMA components manufactured to OEM specifications. Part number ARA330573 ensures you're getting the correct genuine springs designed specifically for ARRMA 1/5 scale vehicles, guaranteeing compatibility and quality.
- What tools do I need to change these springs? — Changing shock springs requires only basic tools: you'll need a spring compressor tool (or you can carefully compress springs by hand with caution), a wrench or hex key to remove the shock cap, and potentially a hex driver depending on your shock design. Most experienced RC owners can complete the job in just a few minutes.
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 Shock Springs, 130mm 2.21N-mm (12.62lb/in) (2) Z-ARA330573 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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