- Pinion Gear Tooth Count: 25T
- Gear Pitch: MOD 0.5
- Bore Diameter: 3.2mm
- Manufacturer: ARRMA
- Part Number: Z-ARA-2176
- EAN: 5052127050739
- Compatible Vehicles: ARRMA 1/16 Mini Kraton 3S (red, blue, teal versions), ARRMA 1/16 Mojave Grom 223S BLX 4x4 (with and without battery and charger, white and teal), ARRMA 1/14 Typhon Grom 223S BLX 4x4 (with and without battery and charger, red, silver, blue versions)
- Scale: 1/16 and 1/14
- Construction Type: CNC-Machined
Overview
The ARRMA Pinion Gear 25T MOD 0.5 CNC 3.2mm Bore (Z-ARA-2176) is a precision-engineered replacement pinion gear designed for ARRMA's 1/16 scale RC vehicles, particularly the Mini Kraton 3S and Mojave Grom 223S models. This component is essential for anyone looking to maintain peak performance from their electric RC car, offering the kind of build quality and precision that ARRMA is recognised for across the RC hobby community in the UK. Whether you're a dedicated basher who pushes your RC vehicle to the limit or a weekend enthusiast looking to keep your model in top condition, this pinion gear is a critical drivetrain component that ensures smooth power delivery from your motor to the wheels.
Pinion gears are fundamental to any electric RC car's drivetrain, acting as the interface between your brushless or brushed motor and the main transmission. The tooth count on a pinion gear directly affects your vehicle's top speed and acceleration characteristics—a higher tooth count like this 25T option will provide slightly higher top speeds compared to lower tooth count alternatives, making it an ideal choice for users looking to optimise their vehicle's performance profile. For RC enthusiasts in the UK seeking genuine ARRMA parts with factory authenticity, this CNC-machined pinion gear represents the perfect replacement or performance upgrade for compatible 1/16 scale models.
ARRMA's commitment to quality is evident in every aspect of this product. The CNC machining process ensures precise tooth geometry and dimensional accuracy, which translates directly to smoother gear mesh, reduced noise, improved efficiency, and longer overall drivetrain life. If you're running one of the compatible Mini Kraton or Grom models, having a quality spare pinion gear on hand is simply sensible maintenance—gears do wear under use, and having replacements ready means your RC car is always race-ready rather than sidelined waiting for parts.
Key Features
- 25T Tooth Count — The 25-tooth configuration strikes an excellent balance between acceleration and top speed for 1/16 scale RC vehicles, offering a performance-oriented setup compared to lower tooth count options that would prioritise raw acceleration at the expense of top-end velocity.
- MOD 0.5 Gear Pitch — The MOD (module) 0.5 specification indicates a precision gear design with specific tooth geometry that ensures perfect mesh compatibility with the spur gears on ARRMA's compatible drivetrain systems, guaranteeing reliable engagement without slop or excessive wear.
- CNC-Machined Construction — Computer numerical control machining produces gears with exceptional precision and consistency, eliminating manufacturing tolerances that could cause noise, vibration, or premature tooth wear in lesser-quality aftermarket gears.
- 3.2mm Bore Diameter — The 3.2mm shaft bore is specifically engineered to fit ARRMA's motor shafts on compatible 1/16 scale models, ensuring a secure fit without the slippage that could occur with poorly matched pinion gears from non-authorised manufacturers.
- Factory ARRMA Authenticity — As a genuine ARRMA part, you can be confident this gear meets the brand's exacting quality standards and will perform identically to the original components that came on your vehicle.
- Durable Material Construction — ARRMA pinion gears are manufactured from quality materials engineered to withstand the stress and torque loads generated by brushless motors in high-performance 1/16 scale electric RC vehicles.
Technical Performance
The ARRMA Pinion Gear 25T MOD 0.5 represents the pinnacle of precision engineering for 1/16 scale RC vehicle drivetrains. The CNC machining process creates gears with exacting tooth profiles that mesh seamlessly with the spur gears in your vehicle's transmission, minimising backlash and vibration whilst maximising power transfer efficiency. This level of precision is particularly important when running brushless motors, which deliver significantly more power than their brushed counterparts—proper gear engagement becomes critical to converting that motor power into controlled wheel rotation without damaging drivetrain components. The MOD 0.5 specification ensures compatibility with ARRMA's factory transmissions on the Mini Kraton 3S, Mojave Grom 223S with batteries and chargers included, and Typhon Grom 223S models, making this a direct factory replacement that requires no modifications or special installation procedures. The 3.2mm bore is precisely toleranced to fit standard ARRMA motor shafts, providing a secure fit that won't slip under load. With a 25-tooth count, this pinion strikes an excellent balance for users prioritising slightly higher top speeds—it's the perfect complement to brushless motor systems that thrive at higher RPM. The gear's durability means it will withstand the repeated acceleration, deceleration, and directional changes inherent in RC car operation, whether you're racing at a local UK track or bashing in your garden.
What's in the Box
- ARRMA Pinion Gear 25T MOD 0.5 with 3.2mm Bore
What You Need to Complete
- Compatible ARRMA 1/16 scale vehicle (Mini Kraton 3S, Mojave Grom 223S, or Typhon Grom 223S)
- Motor and drivetrain already installed on your RC car
- Basic tools such as an Allen key or hex driver to remove and install the pinion gear
Frequently Asked Questions
- What vehicles is the ARRMA Pinion Gear 25T MOD 0.5 compatible with? — This pinion gear is designed for ARRMA's 1/16 scale models including the Mini Kraton 3S (available in red, blue, and teal), Mojave Grom 223S (available with and without battery and charger in white and teal), and Typhon Grom 223S (available in red, silver, and blue with and without battery and charger included). Always verify your vehicle's model number before purchasing to ensure compatibility.
- Why should I replace my pinion gear? — Over time and with use, pinion gears can wear, develop flat spots on the teeth, or become damaged from impacts or extreme driving conditions. A worn pinion gear will cause noise, vibration, and inefficient power transfer. If you notice increased drivetrain noise, loss of top speed, or grinding sounds during acceleration, it's time to replace your pinion gear. Additionally, if you're stepping up from a brushed motor to a brushless motor system, upgrading your pinion gear ensures it can handle the increased power output.
- What is the difference between 25T and other tooth counts? — Pinion tooth count directly affects your vehicle's speed and acceleration. The 25T option provides higher top speed compared to 13T, 15T, 16T, 17T, 18T, 19T, 20T, 21T, 22T, 23T, and 24T alternatives, but with less raw acceleration. Lower tooth counts (like 13T or 15T) prioritise acceleration at the expense of top speed. The 25T is ideal for racers and speed enthusiasts who want maximum velocity on open courses. Choose based on your driving style and the terrain where you'll be using your RC car.
- Is this suitable for beginners? — This is a replacement component rather than a complete vehicle, so it's suited to anyone already running an ARRMA 1/16 scale model. If you're new to RC cars in the UK, you'll want to purchase a complete ready-to-run ARRMA vehicle first; this pinion gear is a maintenance item or upgrade component for existing owners. However, beginners should understand that pinion gears will eventually need replacement as part of normal RC car ownership and maintenance.
- What tools do I need to install this pinion gear? — Installation requires basic tools including an Allen key or hex driver set to fit your motor shaft set screw or collet. ARRMA provides excellent assembly instructions with their vehicles, and pinion gear replacement is typically a five-minute job that even beginners can accomplish with minimal mechanical experience. If you're unsure, your local UK RC retailer can install it for you.
- Does this come in other tooth counts? — Yes, ARRMA manufactures compatible pinion gears in numerous tooth counts including 26T, 27T, 29T, 30T, and 31T options, each offering different performance characteristics. The 25T sits in the middle-to-upper range for top speed. Consult ARRMA's performance guides or speak with experienced RC enthusiasts to select the tooth count that best matches your driving style and local track conditions.
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 Pinion Gear 25T MOD 0.5 CNC 3.2mm Bore Z-ARA-2176 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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