- Brand: ARRMA
- Model Number: Z-ARA311083
- EAN: 5052127041133
- Product Type: Pinion Gear
- Number of Teeth: 21
- Gear Pitch: 0.8 Modulus (0.8Mod)
- Bore Size: 3.2mm (1/8 inch)
- Construction Material: CNC Steel
- Scale Compatibility: 1/8
- RRP: £10.99
- Current Price: £10.44
Overview
The ARRMA 21T 0.8Mod 1/8 inch Bore CNC Steel Pinion Gear (Z-ARA311083) is a precision-engineered replacement pinion gear designed specifically for ARRMA 1/8 scale RC vehicles. This high-quality component is essential for anyone running an ARRMA RC buggy, truggy, or monster truck who wants to maintain peak performance and reliability. Whether you're a competitive racer, a weekend basher, or an RC enthusiast in the UK looking to upgrade or replace a worn pinion gear, this CNC-machined steel gear delivers the durability and precision that serious RC drivers demand.
Pinion gears are one of the most critical drivetrain components in any RC car UK setup. They transfer power from your motor to the spur gear, which then drives the wheels. A worn or damaged pinion can significantly impact your vehicle's performance, acceleration, and overall handling. This genuine ARRMA replacement gear ensures that your 1/8 scale RC model maintains optimal power delivery and smooth, responsive acceleration. The 21-tooth configuration makes this gear suitable for a range of ARRMA models and driving styles, making it a versatile choice for RC enthusiasts across the UK.
Built to ARRMA's exacting standards using CNC steel construction, this pinion gear is engineered to withstand the demands of serious RC bashing and racing. The precise 0.8 modulus (Mod) rating ensures perfect mesh compatibility with ARRMA spur gears, whilst the 3.2mm 1/8 inch bore fits standard ARRMA motor shafts. This is genuine manufacturer-backed hardware, not a cheap aftermarket alternative—when you need reliability and performance, original ARRMA parts deliver every time.
Key Features
- CNC Steel Construction — This pinion gear is precision-machined from hardened steel using computer numerical control (CNC) technology, ensuring absolute accuracy and consistency in tooth profile, pitch diameter, and bore size. This level of precision manufacturing means the gear will mesh perfectly with ARRMA spur gears, delivering smooth power transfer and minimal backlash, which directly translates to better acceleration and more responsive vehicle handling.
- 21-Tooth Configuration — The 21-tooth count offers a well-balanced gear ratio suitable for a variety of ARRMA 1/8 scale vehicles and driving conditions. This tooth count provides a good compromise between acceleration and top speed, making it ideal for both racing and bashing applications across the UK RC scene.
- 0.8 Modulus Specification — The 0.8Mod rating is the industry-standard modulus for ARRMA 1/8 scale drivetrain components. This specification ensures perfect compatibility with ARRMA spur gears and other drivetrain parts, eliminating fitment issues and ensuring optimal meshing for reliable power delivery under load.
- 1/8 Inch Bore (3.2mm) — The precision 3.2mm bore is engineered to fit standard ARRMA motor shafts with minimal play. This tight tolerancing ensures that the pinion gear sits squarely on the motor shaft, preventing wobble and misalignment that could cause premature wear or noise during operation.
- Genuine ARRMA Original Equipment — This is an authorised ARRMA replacement part manufactured to the exact same specifications and quality standards as the components supplied with new ARRMA vehicles. When you buy genuine OEM parts, you're investing in compatibility, reliability, and long-term performance for your RC car UK setup.
- Easy Installation — The straightforward design and standard specifications make this pinion gear quick and simple to install on compatible ARRMA 1/8 scale models. No special tools or modifications are required—simply remove the worn gear and press the new one onto your motor shaft.
Technical Performance
The ARRMA 21T 0.8Mod 1/8 inch Bore CNC Steel Pinion Gear represents the pinnacle of precision drivetrain engineering for serious RC enthusiasts. Manufactured using advanced CNC machining processes, this gear is cut from hardened steel with tolerances measured in fractions of a millimetre, ensuring absolute consistency in tooth profile and pitch diameter. The 0.8 modulus specification is specifically designed for ARRMA's 1/8 scale drivetrain architecture, ensuring perfect mesh engagement with OEM spur gears. The 21-tooth count strikes an excellent balance for 1/8 scale racing and bashing, offering responsive acceleration whilst maintaining reasonable top speed capabilities. The 3.2mm bore is precisely machined to fit ARRMA motor shafts without excessive play, eliminating wobble and ensuring the gear sits perfectly centred on the shaft. This level of precision is critical because even minor misalignment can cause accelerated wear, noise, and loss of efficiency in the drivetrain. In real-world RC car performance, a quality pinion gear like this one will help your brushless RC motor deliver consistent, linear power delivery with minimal vibration. The hardened steel construction provides excellent durability and resistance to tooth stripping, even under the extreme stress of high-powered 1/8 scale racing and aggressive bashing. Whether you're running a competitive race kit or a ready to run RC buggy, this pinion gear will maintain peak performance and reliability.
What's in the Box
- ARRMA 21T 0.8Mod 1/8 inch Bore CNC Steel Pinion Gear
Frequently Asked Questions
- What is a pinion gear and why do I need to replace it? — A pinion gear is a small toothed wheel that mounts directly onto your RC motor shaft. It meshes with a larger spur gear to transfer power from the motor to the wheels. Pinion gears wear over time due to the constant friction and stress of driving, and a worn pinion will cause sluggish acceleration, loss of top speed, and increased noise. Regular inspection and replacement of worn pinion gears is essential maintenance for any RC car, whether you're running a brushless RC buggy or a ready to run RC vehicle. The ARRMA 21T gear ensures your drivetrain operates at peak efficiency.
- Will this pinion gear fit my ARRMA vehicle? — This is a genuine ARRMA replacement part (Z-ARA311083) designed for ARRMA 1/8 scale models that use 0.8Mod pinion gears. The 3.2mm (1/8 inch) bore fits standard ARRMA motor shafts. To confirm compatibility with your specific model, check your vehicle's manual or consult the product compatibility list. If you're unsure, contact RC Model Shop and our team of experienced RC enthusiasts will help you identify the correct pinion gear for your setup.
- What is the difference between this 21-tooth gear and other tooth counts? — Pinion gears come in various tooth counts, typically ranging from 16 teeth to 29 teeth or higher. A lower tooth count (like 16T) provides faster acceleration and higher top speed but requires the motor to work harder. A higher tooth count (like 25T or 29T) provides lower top speed but easier acceleration and less motor strain. The 21-tooth pinion offers an excellent middle-ground suitable for general-purpose racing and bashing. If you want more top speed, consider a lower tooth count; if you prefer easier acceleration and cooler running, consider a higher tooth count. Your choice depends on your driving style and track conditions.
- Is this suitable for beginners? — Yes, this pinion gear is suitable for beginners, but it's important to understand that pinion gears are wear items that require occasional replacement rather than performance upgrades for beginners. If you've just purchased your first ready to run RC car, this gear may not be necessary immediately. However, if you're experiencing performance issues or looking to maintain your vehicle properly, understanding pinion gears is part of becoming a responsible RC enthusiast in the UK. This genuine ARRMA part ensures you're using the correct specification for your vehicle.
- How do I know if my pinion gear is worn and needs replacement? — Signs of pinion gear wear include sluggish acceleration, difficulty reaching top speed, visible damage or missing teeth, grinding or chattering sounds during acceleration, and increased vibration. If you notice any of these symptoms, it's time to inspect your pinion gear. A quick visual check will reveal stripped or damaged teeth. If in doubt, replacement is inexpensive insurance against more serious drivetrain damage. Having a spare pinion gear on hand is good practice for any RC enthusiast.
- What tools do I need to install this pinion gear? — Installation typically requires a small press or a pinion gear puller tool to remove the old gear and install the new one. Most RC enthusiasts in the UK use a dedicated pinion puller tool, which is inexpensive and available from RC retailers. You may also need an Allen key or wrench to access the motor shaft assembly, depending on your vehicle's design. Detailed installation instructions should be available in your vehicle's manual or from ARRMA's support resources. RC Model Shop can provide guidance if you're unsure about the installation process.
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 21T 0.8Mod 1/8 inch Bore CNC Steel Pinion Gear Z-ARA311083 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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