- Product Type: Shock Springs (Pair)
- Manufacturer: ARRMA
- Model Number: ARA330759 / Z-ARA330759
- EAN: 5052127041546
- Spring Length: 70mm
- Spring Rate: 1.28N/mm (7.31lb/in)
- Quantity: 2 springs (pair)
- Material: Precision Manufactured Spring Steel
- Compatible with ARRMA 1/10 KRATON 4S 4X4 RTR Brushless Speed Truck (Model ARA4408V2 - listed as Standard Parts)
- Compatible with ARRMA 1/10 OUTCAST 4S 4X4 RTR Brushless Stunt Truck (Model ARA4410V2 - listed as Standard Parts)
- Also compatible with C-ARA4408V2T4 (Arrma 1/10 Kraton 4X4 4S V2 BLX Speed Monster Truck RTR - Green)
- Also compatible with C-ARA4408V2T3 (Arrma 1/10 Kraton 4X4 4S V2 BLX Speed Monster Truck RTR)
- Also compatible with C-ARA4410V2T4 (Arrma 1/10 OUTCAST 4X4 4S V2 BLX Stunt Truck RTR - Red)
- Also compatible with C-ARA4410V2T3 (Arrma 1/10 OUTCAST 4X4 4S V2 BLX Stunt Truck RTR - Gunmetal)
- Spare Part Category: Suspension Spares
- Customer Rating: 5 out of 5
Overview
The ARRMA Shock Springs: 70mm 1.28N/mm (7.31lb/in)(2) represent essential suspension tuning components for serious RC enthusiasts in the UK and beyond. These precision-engineered shock springs are designed to give you complete control over your vehicle's handling characteristics, allowing you to optimise performance in seconds without complex modifications. Whether you're running a ready to run RC truck or continuously refining your setup, these replacement springs are a critical upgrade option for both the ARRMA 1/10 KRATON 4S and OUTCAST 4S 4X4 brushless models.
If you own an ARRMA brushless speed truck or stunt truck and want to fine-tune how your vehicle responds to terrain changes, jumps and cornering, these shock springs are the perfect solution. The ability to swap spring rates quickly makes them invaluable for track tuning, off-road driving, and competitive racing. RC car UK enthusiasts have long understood that suspension setup can make the difference between a sluggish, unpredictable ride and a vehicle that handles with precision and confidence.
Supplied as a pair and manufactured to exacting standards, these springs deliver the consistency and durability you expect from genuine ARRMA parts. They represent the kind of focused engineering that makes ARRMA one of the most respected names in the ready to run RC market.
Key Features
- Precision Manufactured Spring Steel — These shock springs are manufactured from high-quality spring steel using precision engineering methods, which ensures that each spring delivers consistent performance across multiple use cycles and maintains its characteristics over time. This precision construction guarantees that both springs in the pair perform identically, so your vehicle handles predictably through left and right corners.
- Supplied as a Pair — You receive two shock springs in this package, providing everything you need for a front or rear suspension setup or allowing you to replace both sides simultaneously for balanced handling. Having matched pairs ensures symmetrical suspension behaviour, which is critical for vehicle control and predictable handling on the track or trail.
- 70mm Length — The 70mm length is specifically engineered to fit the ARRMA 1/10 KRATON 4S V2 and OUTCAST 4S V2 4X4 brushless models, providing the correct travel and ride height for these vehicles. This compatibility ensures that the springs integrate seamlessly with your existing suspension geometry without requiring modifications to shock bodies or mounting points.
- 1.28N/mm Spring Rate (7.31lb/in) — The 1.28N/mm metric rating (equivalent to 7.31lb/in for those using imperial measurements) defines how stiffly these springs resist compression. A spring rate of this specification provides a balanced platform for general off-road driving, allowing the suspension to absorb impacts while maintaining predictable handling characteristics across varied terrain.
- Genuine ARRMA Component — As an official ARRMA replacement part, these springs meet all manufacturer specifications and quality standards, guaranteeing compatibility with your truck and reliable performance that matches the engineering standards of your vehicle.
Technical Performance
The ARRMA Shock Springs represent the intersection of material science and practical RC engineering. Built from precision-manufactured spring steel, these components maintain their performance characteristics across hundreds of compression cycles, which is essential when you're regularly driving your RC truck on rough terrain or at racing speeds. The 70mm length is matched specifically to the suspension geometry of the ARRMA 1/10 KRATON 4S V2 and OUTCAST 4S V2 brushless models, meaning the springs work in harmony with the shock bodies and mounting points to deliver the ride height and travel intended by ARRMA's engineers. The 1.28N/mm spring rate translates to predictable handling across a wide range of driving conditions. Softer springs allow greater suspension travel and better absorption of small bumps and impacts, while stiffer springs would reduce travel but increase body control during aggressive cornering and jumps. At 1.28N/mm, these springs strike a middle ground suitable for both general bashing and more serious off-road driving. The consistency of precision manufacturing means both springs perform identically, eliminating the handling imbalances that occur when using mismatched springs on left and right sides. This is crucial because uneven spring rates cause your vehicle to pull to one side under braking, accelerate unevenly through corners, and respond unpredictably to bumps. For brushless RC trucks like the KRATON and OUTCAST, which can generate serious power and speed, having a properly tuned suspension is essential for translating that performance into usable speed rather than bouncing and wallowing through corners.
What's in the Box
- 2 x Shock Spring: 70mm 1.28N/mm (7.31lb/in)
Frequently Asked Questions
- What ARRMA models are these shock springs compatible with? — These 70mm springs are designed as standard parts for the ARRMA 1/10 KRATON 4S 4X4 RTR Brushless Speed Truck and the ARRMA 1/10 OUTCAST 4S 4X4 RTR Brushless Stunt Truck. They may be listed as optional parts for other ARRMA models, so it's worth checking compatibility with your specific vehicle. The springs fit within the existing shock bodies of these trucks without modification.
- Why would I need to replace my shock springs? — Springs wear over time as they are compressed and decompressed during driving, and their rate gradually softens. Additionally, you may want to change your springs to tune your vehicle's handling for different driving styles, track conditions, or weather. A softer spring absorbs bumps better on rough terrain, whilst a stiffer spring provides more control for high-speed driving. Having spare springs on hand means you can experiment with different setups to find what works best for your driving style.
- What is the difference between 1.28N/mm and other spring rates? — The 1.28N/mm rating indicates how much force is required to compress the spring by one millimetre. A lower number like 1.1N/mm would be softer and absorb impacts more easily but might allow excessive body movement, whilst a higher rating like 1.6N/mm would be stiffer, providing better body control but a harder ride. The 1.28N/mm rate is a balanced specification suitable for most off-road driving conditions and provides a good starting point for tuning.
- Do I need any tools to install these springs? — Installation requires removing the shock from your vehicle, compressing the existing spring enough to remove it from the shock body, and then installing the new spring. You'll need a shock tool or a vice to safely compress the springs. If you're not comfortable working on your suspension, we recommend taking your truck to a local hobby shop for professional installation.
- Are these suitable for both beginners and experienced drivers? — Yes, these springs suit any driver. Beginners will find that the 1.28N/mm rate provides stable, predictable handling that's forgiving of driving mistakes. Experienced drivers can use them as a baseline and experiment with different rates to optimise performance for their specific track or terrain.
- How often should I replace my shock springs? — Springs don't typically fail suddenly, but they do soften over time with use. If you notice your truck sitting lower than usual, bottoming out more often, or handling less predictably than when new, your springs may have fatigued and replacement is due. Regular inspection and having spare springs on hand means you can swap them when needed without downtime.
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: 70mm 1.28N/mm (7.31lb/in)(2) Z-ARA330759 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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