- Manufacturer: ARRMA
- Model Number: Z-ARA311087
- EAN: 5052127041096
- Product Type: CNC Steel Pinion Gear
- Scale: 1/8
- Number of Teeth: 25-26T
- Gear Pitch: 0.8 Mod
- Bore Size: 1/8 inch (3.2mm)
- Material: CNC Steel
- Manufacturing Process: CNC Machined
- Recommended for: 1/8 scale RC vehicles
Overview
The ARRMA 25T 0.8Mod 1/8 inch Bore CNC Steel Pinion Gear (Z-ARA311087) is a precision-engineered replacement and upgrade component designed for competitive RC car enthusiasts and serious hobbyists across the UK. This CNC-machined steel pinion gear represents the premium standard in RC drivetrain components, offering the durability and accuracy required for high-performance 1/8 scale RC vehicles. Whether you're running an RC buggy, RC truggy, or other 1/8 scale platform, this pinion gear delivers the reliability and consistency that serious racers demand when pushing their machines to the limit on track or off-road terrain.
ARRMA has built a reputation as one of the world's leading manufacturers of ready-to-run and competition-grade RC vehicles, and their component range reflects the same commitment to quality that makes their complete models so popular. This 25-tooth pinion gear is manufactured to exacting tolerances using CNC machining processes, ensuring perfect engagement with spur gears and smooth power delivery throughout every run. For UK RC enthusiasts looking to replace worn drivetrain components, upgrade their existing setup, or build a competition-ready machine from the ground up, this is an essential part that will help you achieve faster acceleration and more reliable performance on every drive.
As a dedicated UK RC hobby retailer, we stock genuine ARRMA components because we understand that quality matters when you're investing in your RC car UK experience. This pinion gear is the kind of detail that separates casual bashers from serious competitors, and having the right components fitted to your machine makes a measurable difference in acceleration response, handling consistency, and overall reliability during intense driving sessions.
Key Features
- CNC Steel Construction — This pinion gear is manufactured from hardened steel using precision CNC machining processes, which ensures exceptional durability and wear resistance even under the sustained stress of competitive racing or aggressive bashing sessions, delivering longevity that softer materials simply cannot match.
- 25 Teeth Configuration — The 25-tooth design provides the optimal balance between acceleration and top speed for 1/8 scale RC vehicles, allowing you to customise your gearing setup to match your driving style and track conditions without needing to completely redesign your drivetrain.
- 0.8 Mod Gear Pitch — The 0.8 modulus specification ensures perfect meshing compatibility with matching spur gears in the ARRMA ecosystem, guaranteeing smooth engagement, minimal backlash, and consistent power transfer with every throttle input during both high-speed runs and technical maneuvering.
- 1/8 inch Bore (3.2mm) — The precisely-machined 1/8 inch bore diameter (3.2mm) is engineered to fit standard 1/8 scale RC motor shafts with tight tolerances, ensuring secure mounting that eliminates wobble, slip, and runout issues that would otherwise compromise acceleration response and efficiency.
- Precision Engineering — ARRMA's commitment to CNC manufacturing means every tooth is cut to identical specifications, eliminating the variances found in mass-produced alternatives and delivering the consistent engagement that competitive drivers rely on when lap times matter.
- Direct ARRMA Component — As a genuine ARRMA replacement part, this pinion gear is designed and tested to work seamlessly within ARRMA's 1/8 scale vehicle platforms, guaranteeing compatibility and performance that aftermarket alternatives cannot reliably provide.
Technical Performance
This ARRMA pinion gear is engineered to deliver the precision and durability that modern 1/8 scale RC racing demands. The CNC steel construction provides superior hardness compared to brass or aluminium alternatives, meaning the teeth maintain their sharp profiles over extended use and resist the deformation that softer materials experience under load. With 25 teeth in a 0.8 modulus specification, this gear integrates seamlessly into ARRMA's drivetrain architecture, providing optimal tooth engagement with matching spur gears. The 1/8 inch bore (3.2mm) is machined to tight tolerances to accommodate standard 1/8 scale motor shafts, eliminating play that would reduce efficiency and create binding during rapid acceleration or deceleration. For competitive RC car UK racers, this level of precision is essential—every millisecond counts when you're pushing a brushless RC buggy or RC truggy around a demanding track layout. The steel material choice ensures that this component will outlast multiple racing seasons with proper maintenance, making it an investment in long-term reliability rather than a consumable part that needs frequent replacement. Whether you're running this on a 2S, 3S, or higher-capacity LiPo battery system, the mechanical advantage provided by this 25-tooth pinion gear remains consistent and predictable across the entire range of motor speeds your ESC and battery combination can deliver.
What's in the Box
- ARRMA 25T 0.8Mod CNC Steel Pinion Gear
What You Need to Complete
- Matching spur gear (sold separately) compatible with ARRMA 1/8 scale vehicles
- ARRMA 1/8 scale RC vehicle platform
- Standard 1/8 scale motor with appropriate shaft size
- Tools for drivetrain assembly and adjustment
Frequently Asked Questions
- What ARRMA 1/8 scale vehicles is this pinion gear compatible with? — This is a genuine ARRMA 25T 0.8Mod pinion gear designed for 1/8 scale ARRMA platforms. The 25-tooth, 0.8 modulus specification ensures compatibility with the spur gears and motor mounts found on ARRMA's 1/8 scale vehicle range. You should verify that your specific model uses the same gear pitch and bore size, but if you own an ARRMA 1/8 scale buggy, truggy, or similar platform, this component will integrate directly into your existing drivetrain.
- Why should I choose a CNC steel pinion gear over plastic or brass alternatives? — CNC steel pinion gears offer significantly superior durability and longevity compared to softer materials. Steel teeth resist deformation and wear far better than brass, and they maintain their precise tooth profiles over hundreds of charge cycles. For RC car UK enthusiasts who race competitively or bash frequently, steel gears reduce the frequency of component replacement, ultimately saving money while delivering more consistent performance lap after lap.
- How do I know what tooth count I need for my RC vehicle? — Pinion gear tooth count directly affects your acceleration and top speed balance. The 25-tooth specification on this part offers a mid-range setup suitable for most 1/8 scale driving styles. Lower tooth counts (such as 23T or 24T) increase acceleration at the expense of top speed, whilst higher counts (26T, 27T) favour top speed over punch off the line. Your choice should depend on your track layout, driving style, and the spur gear you're pairing this with—our team at RC Model Shop can help you select the optimal gearing for your specific needs.
- What is the difference between 0.8Mod and other gear pitch specifications? — The modulus (Mod) specification describes the size and spacing of the gear teeth. A 0.8Mod gear has smaller, more closely-spaced teeth compared to larger modulus gears like 1.0Mod or 1.5Mod. In 1/8 scale RC applications, 0.8Mod is the standard specification that ensures proper meshing with matching components. Using gears of different modulus values will result in poor engagement, increased backlash, and potential drivetrain damage.
- Is this suitable for beginners? — This is a specialist replacement component rather than a complete vehicle or beginner-focused product. If you're new to RC cars, you'll benefit from starting with a complete ready-to-run model, and you can upgrade to precision components like this CNC steel pinion gear as you develop your skills and begin racing competitively. However, if you already own an ARRMA 1/8 scale vehicle and need a replacement pinion gear, this is an excellent choice that will improve reliability regardless of your experience level.
- Do I need special tools to install this pinion gear? — Installation requires basic RC maintenance tools including an appropriate socket or wrench to hold the motor shaft whilst you secure the pinion gear. ARRMA's drivetrain components are designed for straightforward installation, and detailed assembly instructions are available in your vehicle's manual. If you're unfamiliar with drivetrain work, our team at RC Model Shop can provide guidance, or you can bring your vehicle to our Walsall store for professional installation.
- Will this pinion gear work with any motor, or does it need a specific size? — This pinion gear features a 1/8 inch (3.2mm) bore designed for standard 1/8 scale motor shafts. As long as your motor has a compatible shaft size, this gear will fit. The gear's performance is independent of motor size or KV rating—it will work equally well with smaller brushed motors or higher-performance brushless systems, allowing you to upgrade or change motors without needing to replace your drivetrain components.
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 25T 0.8Mod 1/8 inch Bore CNC Steel Pinion Gear Z-ARA311087 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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