- Manufacturer: ARRMA
- Part Number: Z-ARA-2178
- EAN Code: 5052127050708
- Gear Type: Pinion Gear
- Tooth Count: 27T
- Gear Pitch: MOD 0.5
- Bore Diameter: 3.2mm
- Manufacturing Process: CNC Machined
- Compatible Models: ARRMA 1/16 Mini Kraton 3S, ARRMA 1/16 MOJAVE GROM 223S BLX 4x4, ARRMA 1/14 TYPHON GROM 223S BLX 4x4
- Compatible Colour Variants: Blue, Red, Teal, Black, White, Silver
- Scale: 1/16 and 1/14
Overview
The ARRMA Pinion Gear 27T MOD 0.5 CNC 3.2mm Bore is a precision-engineered replacement pinion gear designed specifically for ARRMA's smaller-scale RC vehicles. Whether you're running a 1/16 Mini Kraton 3S, 1/16 MOJAVE GROM 223S, or 1/14 TYPHON GROM 223S, this CNC-machined pinion gear offers reliable performance and durability for hobbyists and serious RC enthusiasts across the UK. Pinion gears are essential drivetrain components that directly affect your RC car's acceleration, top speed, and overall handling characteristics, making this a critical upgrade or replacement part for anyone looking to optimise their vehicle's performance.
As an OEM ARRMA part, this 27-tooth pinion gear is manufactured to the highest standards using CNC machining processes, ensuring perfect tooth profile consistency and excellent mesh with your spur gear. The 3.2mm bore diameter ensures a secure fit on motor shafts, while the MOD 0.5 gear pitch specification maintains compatibility with ARRMA's transmission systems. For anyone in the UK who runs compact ARRMA RC buggies and trucks, this pinion gear is an essential spare to keep in your pit box for emergency replacements or performance tuning.
This is the perfect solution if you've experienced wear on your existing pinion gear or if you're looking to fine-tune your RC car's speed and torque characteristics. The 27-tooth configuration provides a mid-range ratio that balances acceleration with top speed, making it suitable for a variety of driving conditions and terrain types across different ARRMA platforms.
Key Features
- CNC-Machined Construction — This pinion gear is precision-manufactured using computer numerical control machining, which ensures exact tooth profiles, consistent material density, and superior durability compared to standard stamped gears, resulting in quieter operation and longer service life in your RC car.
- 27-Tooth Configuration — The 27-tooth count provides an ideal balance between acceleration and top speed for small-scale ARRMA vehicles, allowing you to achieve responsive throttle response without sacrificing overall velocity on the track or trail.
- MOD 0.5 Gear Pitch — This modulus specification ensures perfect meshing compatibility with ARRMA's spur gears and transmission systems, guaranteeing smooth power delivery and minimising noise, vibration, and wear during operation.
- 3.2mm Bore Diameter — The precisely sized bore fits securely onto the motor shafts used in ARRMA's compact-scale models, preventing slipping or misalignment whilst allowing for quick and easy installation and removal during maintenance or upgrades.
- Genuine OEM Part — As an authentic ARRMA component, you can be confident in compatibility, quality control, and performance consistency across the entire ARRMA ecosystem of 1/16 and 1/14 scale RC vehicles.
- Multi-Vehicle Compatibility — This single pinion gear is compatible with numerous ARRMA models including the Mini Kraton 3S, MOJAVE GROM 223S, and TYPHON GROM 223S in multiple colour variants, making it a versatile spare part for UK RC enthusiasts with multiple vehicles.
Technical Performance
The ARRMA Pinion Gear 27T MOD 0.5 CNC 3.2mm Bore represents the pinnacle of small-scale RC drivetrain engineering. Every aspect of this component has been carefully engineered to deliver reliable, consistent performance in ARRMA's lighter-duty 1/16 and 1/14 scale platform vehicles. The CNC machining process produces gears with dimensional accuracy measured in fractions of a millimetre, ensuring that tooth engagement with the spur gear is optimal across the full range of throttle inputs and driving styles. This precision engineering directly translates to reduced friction losses, cooler running temperatures, and extended drivetrain lifespan — all critical factors for weekend bashers and competitive RC racers alike. The MOD 0.5 specification is a standard gear pitch calculation that ensures this pinion mates perfectly with ARRMA's spur gears without binding or slipping. The 3.2mm bore diameter has been designed specifically for the motor shafts fitted to ARRMA's compact RTR (Ready To Run) and kit vehicles, providing a secure interference fit that eliminates backlash and wobbling. The 27-tooth count positions this gear in the middle of ARRMA's pinion range, offering drivers a neutral platform from which to adjust performance: stepping down to a lower tooth count increases acceleration but reduces top speed, whilst moving to a higher tooth count produces the opposite effect. For UK RC enthusiasts running stock ARRMA vehicles or those making modest performance modifications, this 27T pinion represents an excellent baseline for tuning and optimisation.
What's in the Box
- 1x ARRMA Pinion Gear 27T MOD 0.5 CNC 3.2mm Bore
Frequently Asked Questions
- Which ARRMA models is this 27T pinion gear compatible with? — This pinion gear is designed for ARRMA's 1/16 and 1/14 scale vehicles, specifically the Mini Kraton 3S (available in blue, red, and teal), the MOJAVE GROM 223S (available in teal, black, and white), and the TYPHON GROM 223S (available in blue, silver, and red). Always verify your vehicle's model number before ordering to ensure compatibility with your specific RC car.
- What does MOD 0.5 mean in the gear specification? — MOD stands for modulus, which is a standard gear pitch measurement used in the RC industry. MOD 0.5 specifically refers to the tooth size and spacing of the gear, and it's crucial that your pinion and spur gears match this specification to ensure proper meshing, smooth operation, and longevity of your drivetrain.
- Will this pinion gear fit my current RC car? — The 3.2mm bore diameter is specifically sized for ARRMA vehicles in the 1/16 and 1/14 scale range. Before purchasing, check your vehicle's documentation or contact us to confirm that your RC car uses this bore size and MOD 0.5 gearing. Attempting to install a pinion gear with the wrong bore diameter or modulus could damage your motor shaft and transmission.
- How often do I need to replace my pinion gear? — Pinion gear lifespan depends on driving style, terrain, maintenance practices, and the condition of your spur gear. Aggressive driving on abrasive surfaces will wear gears faster than casual weekend bashing on grass. Inspect your pinion gear regularly for signs of chipping, cracking, or tooth wear, and replace it as soon as wear becomes visible to prevent secondary damage to your motor and spur gear.
- Can I use a different tooth count to change my RC car's performance? — Yes, adjusting the tooth count of your pinion gear is one of the most effective ways to tune your RC car's performance. A lower tooth count (such as 25T or 26T) increases acceleration and torque but reduces top speed and places greater stress on the drivetrain. A higher tooth count (such as 28T, 29T, 30T, or 31T) decreases acceleration but increases top speed and reduces motor load. Experiment cautiously with small increments to find the sweet spot for your specific driving style and terrain.
- Is this a genuine ARRMA part or an aftermarket alternative? — This is a genuine OEM ARRMA pinion gear, indicated by the part number Z-ARA-2178. Purchasing authentic ARRMA parts ensures compatibility, proper fit, and the manufacturer's quality assurance standards that third-party alternatives may not provide.
- What tools do I need to install this pinion gear? — Installation typically requires basic RC maintenance tools including an Allen wrench or hex key set, a pinion gear puller (which safely removes the old pinion without damaging the motor shaft), and potentially a small hammer and punch for fitting the new pinion. Refer to your vehicle's service manual for detailed installation instructions specific to your ARRMA model.
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 27T MOD 0.5 CNC 3.2mm Bore Z-ARA-2178 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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