- Part Type: Pinion Gear
- Manufacturer: ARRMA
- Part Number: Z-ARA-2182
- EAN Code: 5052127050760
- Number of Teeth: 31T
- Gear Pitch: MOD 0.5
- Motor Shaft Bore: 3.2mm
- Material: Steel (hardened)
- Manufacturing Process: CNC (Computer Numerical Control)
- Included Set Screw: M3 x 4mm
- Compatible with Mini Kraton 3S (1/16 scale)
- Compatible with MOJAVE GROM 223S BLX (1/16 scale)
- Compatible with TYPHON GROM 223S BLX (1/14 scale)
- Direct Replacement Component
- Precision Manufactured Tooth Profile
- Precision Manufactured Set Screw Hole
Overview
The ARRMA Pinion Gear 31T MOD 0.5 CNC 3.2mm Bore is a precision-engineered replacement component designed for serious RC enthusiasts and bashers who demand reliability and performance from their electric RC cars and trucks. Whether you're running a 1/16 scale Mini Kraton, MOJAVE GROM, or TYPHON GROM buggy, this CNC-manufactured pinion gear delivers the durability and smooth operation you need to keep your RC vehicle performing at its best. As an essential drivetrain component, the pinion gear works in harmony with your spur gear to transfer power from the motor to the transmission, making it a critical element in your RC car's overall performance chain.
This tough steel pinion gear is manufactured to exacting specifications using CNC (Computer Numerical Control) machining, ensuring consistent tooth profiles and precise tolerances that keep your RC buggy running smoothly through extreme bashing conditions. The 31-tooth configuration provides a specific gear ratio that affects your vehicle's speed and torque characteristics, allowing you to fine-tune performance to match your driving style and track conditions. For RC hobbyists in the UK seeking a genuine ARRMA part with proven reliability, this pinion gear represents an excellent choice for maintenance, repair, or performance tuning of compatible models.
If you're experiencing worn teeth, stripped gears, or simply looking to upgrade or modify your RC vehicle's performance characteristics, having a quality replacement pinion gear on hand is essential. The ARRMA Pinion Gear 31T MOD 0.5 CNC 3.2mm Bore is the direct replacement component you need, backed by ARRMA's reputation for engineering excellence in the RC hobby.
Key Features
- 31-Tooth Configuration — The 31-tooth design is engineered to work with MOD 0.5 spur gears, providing a specific gear ratio that affects acceleration and top speed characteristics; this tooth count is ideal for models engineered to use this specification, ensuring proper mesh and drivetrain efficiency.
- Strong and Durable Steel Construction — Manufactured from hardened steel, this pinion gear is built to withstand the punishment of aggressive RC bashing, racing, and extreme driving conditions without premature tooth wear or breakage.
- CNC-Manufactured Precision — Computer numerical control manufacturing ensures every gear tooth is cut to identical specifications with precise profiles, delivering smooth operation and minimal backlash in your drivetrain for better handling and responsiveness.
- MOD 0.5 Gear Pitch — The MOD 0.5 (0.5 module) specification ensures compatibility with matching spur gears on your RC vehicle, maintaining proper gear mesh and engagement for optimal power transfer and longevity.
- 3.2mm Motor Shaft Bore — The precisely machined 3.2mm bore is engineered to fit standard ARRMA motor shafts, providing a secure fit that prevents slipping under load during acceleration and high-powered running.
- Included M3 x 4mm Set Screw — Every gear comes with the necessary M3 x 4mm set screw for secure mounting onto your motor shaft, ensuring the pinion stays in place even during aggressive acceleration and hard cornering.
Technical Performance
The ARRMA Pinion Gear 31T MOD 0.5 is engineered for reliable performance in small-scale brushless RC vehicles including the 1/16 Mini Kraton 3S, 1/16 MOJAVE GROM 223S BLX, and 1/14 TYPHON GROM 223S BLX models. The 31-tooth pinion, combined with MOD 0.5 specifications, creates a precise gear ratio that has been validated by ARRMA engineers for these platforms. CNC manufacturing ensures that tooth profiles are identical across the entire gear, eliminating variations that could cause vibration, noise, or accelerated wear. The hardened steel material provides exceptional durability, resisting the wear that comes from repeated engagement with the spur gear during thousands of acceleration cycles. The 3.2mm bore is precisely engineered to fit motor shafts without excessive play, ensuring positive power transfer and preventing gear slippage that would compromise performance. The inclusion of the M3 x 4mm set screw provides the mechanical security needed to keep the gear firmly mounted during hard acceleration, braking, and cornering manoeuvres. For RC car enthusiasts and bashers in the UK who demand precision components that will perform reliably in their favourite models, this CNC pinion gear represents excellent value and engineering integrity.
What's in the Box
- 1 x 31T MOD 0.5 Pinion Gear
- 1 x M3 x 4mm Set Screw
Compatible Models
- ARRMA 1/16 Mini Kraton 3S (Battery and Charger Included) — Blue, Red, and Teal variants
- ARRMA 1/16 MOJAVE GROM 223S BLX 4x4 Desert Truck (with and without Battery/Charger) — Black, Teal, and White variants
- ARRMA 1/14 TYPHON GROM 223S BLX 4x4 Buggy (with and without Battery/Charger) — Blue, Silver, and Red variants
Frequently Asked Questions
- What is a pinion gear and why do I need a replacement? — A pinion gear is the small gear mounted directly on your electric motor shaft that meshes with the larger spur gear to transfer power to your RC vehicle's transmission. Over time, through normal use and aggressive bashing, the teeth on your pinion gear can become worn, damaged, or stripped. When this happens, your vehicle loses efficiency and performance. The ARRMA Pinion Gear 31T MOD 0.5 is a direct replacement component that restores your drivetrain to original specifications and performance characteristics. Having a spare on hand is a smart investment for anyone who drives their RC car regularly.
- What is the difference between MOD 0.5 and other gear specifications? — The MOD (module) specification determines the tooth size and pitch of the gear. MOD 0.5 gears have smaller teeth compared to MOD 0.8 or larger specifications. ARRMA has engineered their small-scale models to use MOD 0.5 components for optimal efficiency and performance. Using the correct MOD specification is critical — mixing different MOD gears will cause poor mesh, backlash, and accelerated wear. This pinion gear is specifically engineered for MOD 0.5 spur gears and drivetrain components.
- Will this pinion gear fit my ARRMA RC model? — The ARRMA Pinion Gear 31T MOD 0.5 CNC 3.2mm Bore is specifically designed for compatibility with the 1/16 Mini Kraton 3S, 1/16 MOJAVE GROM 223S, and 1/14 TYPHON GROM 223S models. Before purchasing, confirm your specific model variant matches the compatible models listed. The 3.2mm bore is engineered for standard ARRMA motor shafts in these platforms. If you're unsure of compatibility, our expert team at RC Model Shop can assist you in identifying the correct component for your model.
- How do I install the pinion gear? — The pinion gear is mounted directly onto your motor shaft with the included M3 x 4mm set screw. You'll need to remove your motor from the vehicle, slide the gear onto the shaft, and tighten the set screw firmly to prevent slippage during operation. The set screw should be tightened securely but not so hard that you strip the threads. If you're unsure about installation, we recommend consulting your vehicle's manual or seeking assistance from experienced RC enthusiasts in the community.
- What is the difference between 18T, 25T, 31T, and other tooth counts? — The tooth count directly affects your vehicle's gear ratio and performance characteristics. Lower tooth counts like 18T provide higher top speeds but lower torque, making acceleration slower. Higher tooth counts like 31T provide more torque and better acceleration but lower top speed. The choice between tooth counts depends on your driving style, track conditions, and performance preferences. The 31T configuration in this gear is ideal for drivers who prioritise acceleration and strong pulling power over maximum speed.
- Is the CNC manufacturing process important? — Yes, absolutely. CNC (Computer Numerical Control) manufacturing ensures that every tooth on the pinion gear is cut to identical specifications with precise profiles. This consistency delivers smoother operation, less vibration and noise, and more even wear distribution across all teeth. Compared to gears produced using less precise methods, CNC-manufactured gears like this one provide superior reliability and longevity, making them a worthwhile investment for serious RC enthusiasts.
- What is the purpose of the M3 x 4mm set screw? — The set screw is the critical component that locks the pinion gear onto your motor shaft, preventing it from slipping or rotating independently during operation. Without a properly secured pinion gear, your vehicle would lose drive and power transmission capability would fail. The included M3 x 4mm set screw is the correct specification for ARRMA models, and should always be tightened securely before running your vehicle.
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 31T MOD 0.5 CNC 3.2mm Bore 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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