Overview
The ARRMA Shock Springs 120mm 2.15N/mm (12.28lb/in) are essential tuning components for serious RC enthusiasts looking to dial in their vehicle's handling characteristics. Whether you're running an ARRMA 1/5 scale brushless speed truck like the KRATON 8S or the OUTCAST 8S, these precision-engineered shock springs allow you to fine-tune your suspension setup in seconds, making them indispensable for anyone wanting to optimise their RC car UK performance. Available as a pair, these springs represent genuine ARRMA original parts that deliver the consistency and durability expected from a premium RC manufacturer.
Tuning your RC vehicle's suspension is one of the most effective ways to improve handling, stability and overall driving experience. These shock springs are designed to work seamlessly with ARRMA's assembled shock sets and provide the flexibility to adjust your vehicle's ride height, chassis geometry and suspension stiffness to match your driving style and terrain conditions. Whether you're a seasoned competitor, a weekend basher, or exploring the ready to run RC truck market for the first time, having a selection of different spring rates in your pit box is a smart approach to getting the most from your ARRMA brushless RC vehicle.
These 120mm shock springs are manufactured to the exacting standards ARRMA is renowned for, combining precision engineering with practical durability. The 2.15N/mm (12.28lb/in) spring rate sits in the mid-range of ARRMA's spring options, making it an excellent all-around choice for general driving across various surfaces and conditions. Upgrading or replacing your shock springs is a straightforward maintenance task that requires no specialist tools or technical knowledge, making it accessible to RC enthusiasts of all skill levels.
Key Features
- Precision manufactured spring steel construction — These shock springs are crafted from high-quality spring steel that has been precision manufactured to deliver consistent performance and reliable functionality across countless driving sessions, ensuring your suspension responds predictably every time you hit the track or terrain.
- 120mm length specification — The 120mm length is engineered to match ARRMA's shock absorber design, ensuring proper fitment and correct suspension geometry when installed on compatible models including the KRATON 8S and OUTCAST 8S brushless trucks.
- 2.15N/mm spring rate — This moderate spring rate (12.28lb/in) provides an excellent balance between comfort and control, offering sufficient suspension compliance for rough terrain whilst maintaining the chassis stiffness needed for responsive handling and stability during aggressive driving manoeuvres.
- Long-lasting durability — The hardened spring steel construction resists fatigue and maintains its spring properties over extended use, meaning you can rely on consistent suspension performance season after season without premature sagging or loss of spring force.
- Supplied as a pair — You receive two shock springs in this package, allowing you to replace both shocks or maintain a spare set for backup and comparison testing at the track.
- Direct fitment compatibility — Designed specifically for ARRMA vehicles, these springs offer hassle-free installation on compatible shock absorber assemblies without requiring modification or adaptation.
Technical Performance
The ARRMA Shock Springs represent a critical component in your RC vehicle's suspension system, directly affecting how the chassis responds to bumps, landing impacts and cornering forces. With a spring rate of 2.15N/mm (12.28lb/in), these springs strike an ideal middle ground in ARRMA's spring lineup, offering versatility across a range of driving conditions and styles. The 120mm length ensures these springs work in harmony with ARRMA's shock absorber design, which features precision-manufactured red anodised aluminium shock bodies and polished stainless steel shock shafts. The springs are engineered to compress and extend smoothly within the shock bore whilst maintaining consistent force delivery. Spring steel, the chosen material, offers superior fatigue resistance compared to inferior spring materials, ensuring your suspension maintains its tuning characteristics through thousands of compression cycles. Whether you're running these springs on a 1/5 scale brushless truck like the KRATON 8S EXB with its six-millimetre shock shafts and heavy-duty rod ends, or experimenting with different spring rates to optimise handling, the quality engineering behind these components ensures reliable performance. The 2.15N/mm rate pairs excellently with ARRMA's pre-filled shock oil systems and standard piston configurations, making spring rate adjustment a straightforward path to suspension tuning without requiring additional modifications to your shock absorber assembly.
What's in the Box
- 2 x Shock Spring 120mm, 2.15N/mm (12.28lb/in)
What You Need to Complete
- Compatible ARRMA shock absorber assembly to install these springs into
- ARRMA vehicle compatible with the shock springs (KRATON 8S, KRATON 8S EXB, OUTCAST 8S EXB, or other models listed in fitment guide)
Frequently Asked Questions
- What ARRMA vehicles are these shock springs compatible with? — These 120mm shock springs are listed as standard or optional parts for the ARRMA KRATON 8S 4X4 RTR (ARA110002), KRATON 8S EXB 4X4 Roller (ARA5208), KRATON 8S EXB AVC 4X4 RTR (ARA5808V2T1), and OUTCAST 8S EXB AVC 4X4 RTR (ARA5810V2T1). Always check your specific model's parts manual to confirm fitment before purchasing.
- What is the difference between the 2.15N/mm springs and other ARRMA shock spring options? — ARRMA offers different spring rates to suit varying preferences and conditions. The 2.15N/mm (12.28lb/in) rate is a medium-stiffness option positioned between softer and stiffer alternatives. Softer springs (lower N/mm) provide more suspension compliance for bumpy terrain and comfort, whilst stiffer springs (higher N/mm) offer more support for precise handling and resistance to chassis bottoming during hard landings or jumps.
- Do I need any special tools to install these shock springs? — Installation is straightforward and requires no specialist tools. You simply need to remove your existing shock springs (if present) from your shock absorber assembly and slide the new springs on. Some users prefer to use the threaded spring preload adjusters that come with ARRMA shock sets for fine-tuning ride height, but basic spring replacement requires only basic hand strength.
- How often should I replace my shock springs? — Shock springs maintain their performance characteristics for extended periods under normal use. However, if you notice reduced suspension compliance, increased sagging, or inconsistent handling, it may be time to inspect or replace your springs. Many enthusiasts keep spare spring sets in different rates for testing and tuning purposes.
- Can I use these springs on shocks from other brands? — These springs are engineered specifically for ARRMA shock absorber designs with 120mm length and matching bore diameters. Using them on incompatible shocks may result in poor fitment or performance. Always verify compatibility with your specific shock assembly before installation.
- Is this suitable for beginners? — Yes, absolutely. Spring selection and replacement is an excellent entry point into suspension tuning for beginners. The straightforward installation process requires no special knowledge, and experimenting with different spring rates is an educational way to understand how suspension affects vehicle handling. Starting with the medium 2.15N/mm rate is a smart approach before exploring softer or stiffer options.
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, 120mm 2.15N/mm (12.28lb/in) (2) Z-ARA330616 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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