This tough steel 18T MOD 0.5 Pinion Gear provides a direct replacement for your kit item.
Includes
1 x 18T Mod 0.5 Pinion Gear
1 x M3 x 4mm Set Screw
Features
- Strong and durable steel for long-lasting performance in extreme RC conditions
- Precision manufactured tooth profile for smooth operation
- Precision manufactured set screw hole
- For 3.2mm motor shaft
- Brand: ARRMA
- Part Number: Z-ARA-2031
- ARRMA Part Number: ARA-2031
- EAN Code: 5052127050173
- Product Type: Pinion Gear
- Tooth Count: 18T
- Gear Pitch: MOD 0.5
- Motor Shaft Bore: 3.2mm
- Material: Steel (hardened)
- Manufacturing Method: CNC precision machined
- Set Screw Size: M3 x 4mm
- Compatible Vehicle Models: ARRMA 1/16 Mini Kraton 3S (all variants), ARRMA 1/16 Mojave Grom 223S (all variants), ARRMA 1/14 Typhon Grom 223S (all variants)
- Application: Brushless RC vehicles requiring 3.2mm motor shaft pinion
- Set Screw Hole: Precision manufactured M3 specification
- Included Components: 1 x 18T MOD 0.5 Pinion Gear, 1 x M3 x 4mm Set Screw
Overview
The ARRMA Pinion Gear 18T MOD 0.5 CNC 3.2mm Bore is a precision-engineered replacement component designed for RC enthusiasts across the UK who demand reliability and performance from their brushless RC vehicles. Whether you're running an ARRMA 1/16 Mini Kraton 3S speed monster truck, a 1/16 Mojave Grom desert truck, or a 1/14 Typhon Grom buggy, this pinion gear is the exact OEM replacement part you need to maintain peak drivetrain performance. This tough steel pinion gear has been manufactured to exacting CNC specifications and provides a direct replacement for your kit item, ensuring your RC car UK setup continues to deliver the speed and reliability you expect.
As a critical component in your RC vehicle's transmission system, the pinion gear directly impacts acceleration, top speed, and overall drivetrain efficiency. The 18-tooth configuration offers a balanced approach to gearing, making it an ideal choice for drivers who want smooth power delivery without sacrificing top-end velocity. RC car enthusiasts and weekend bashers alike will appreciate the straightforward installation process and the confidence that comes with fitting genuine ARRMA parts to their ready to run RC models.
When your existing pinion gear wears out or becomes damaged through intense RC driving sessions, having access to quality replacement parts is essential. The ARRMA Pinion Gear 18T MOD 0.5 CNC 3.2mm Bore ensures your brushless RC buggy, truck, or speed vehicle continues to perform at its best, whether you're competing in organised RC events or enjoying casual backyard bashing with friends.
Key Features
- Strong and Durable Steel Construction — Manufactured from high-quality hardened steel, this pinion gear delivers long-lasting performance even in extreme RC driving conditions, resisting wear and tooth degradation during extended use and high-stress manoeuvres.
- Precision CNC Manufacturing — Every pinion gear is produced using computer numerical control machining to ensure consistent quality, precise tooth profiles, and exact dimensional tolerances that guarantee smooth engagement with your spur gear.
- Smooth Tooth Profile — The precision-manufactured tooth profile ensures seamless meshing with your vehicle's spur gear, delivering smooth power transfer, reduced backlash, and quieter operation during acceleration and top-speed runs.
- Precision Set Screw Hole — The accurately machined M3 set screw hole allows for secure attachment to your motor shaft without stripping or loosening, maintaining alignment and preventing slippage during hard driving.
- 3.2mm Motor Shaft Compatibility — Designed specifically for the standard 3.2mm motor shaft bore found on brushless motors fitted to modern ARRMA RC vehicles, ensuring perfect fitment and eliminating guesswork during installation.
- Complete Installation Kit — Includes the pinion gear plus an M3 x 4mm set screw, providing everything needed for hassle-free installation on your RC car without requiring additional hardware purchases.
- 18-Tooth Configuration — The 18-tooth count offers an optimal balance between acceleration and top speed, making this gear suitable for both speed-focused driving and general RC car enjoyment across varied terrain.
Technical Performance
The ARRMA Pinion Gear 18T MOD 0.5 CNC 3.2mm Bore represents genuine OEM engineering designed specifically for ARRMA's brushless RC vehicle lineup. Manufactured to MOD 0.5 specifications, this gear pitch standard is widely recognised across the RC industry and ensures compatibility with corresponding spur gears in modern ARRMA transmissions. The precision CNC manufacturing process guarantees that each tooth is machined to exact tolerances, creating a perfect gear profile that minimises friction, reduces noise, and maximises power transfer efficiency. This is particularly important for brushless RC vehicles where electric motor performance depends on clean, efficient drivetrain engagement. The hardened steel construction provides exceptional durability compared to plastic or lower-grade materials, ensuring the pinion gear can withstand the demanding torque loads generated by modern brushless motors and 3S LiPo batteries common in ready to run RC models. The 3.2mm bore precisely matches the motor shafts found on brushless motors integrated into ARRMA's latest generation vehicles, whilst the included M3 x 4mm set screw provides positive locking to prevent rotation under acceleration. Whether you're running at maximum throttle on a high-speed circuit or bashing through rough terrain, this pinion gear delivers consistent performance session after session.
What's in the Box
- 1 x 18T MOD 0.5 Pinion Gear (steel, CNC machined, 3.2mm bore)
- 1 x M3 x 4mm Set Screw (for secure motor shaft attachment)
Frequently Asked Questions
- What ARRMA vehicles is this pinion gear compatible with? — This 18T MOD 0.5 pinion gear is a standard component fitted to several ARRMA models including the 1/16 Mini Kraton 3S (both standard and battery/charger included versions), the 1/16 Mojave Grom 223S in multiple colour variants, and the 1/14 Typhon Grom 223S 4WD buggy platform. It is compatible with models across the GROM line that utilise 3.2mm motor shafts and MOD 0.5 transmission gearing.
- Is this a genuine ARRMA part? — Yes, this is the genuine OEM pinion gear manufactured by ARRMA specifically for their brushless RC vehicles. The ARRMA part number is ARA-2031, and it carries the quality assurance and design validation that ARRMA applies to all original equipment parts for their ready to run RC models.
- How often will I need to replace this pinion gear? — The lifespan of a pinion gear depends on your driving intensity and maintenance habits. Casual weekend bashers with RC cars UK might run a single gear for months or longer, whilst competitive drivers and those using high-torque 3S LiPo setups may notice wear more quickly. Regular inspection for tooth damage, cracking, or unusual wear patterns will help you determine when replacement is necessary.
- Can I use a different tooth count? — The 18-tooth configuration represents the standard OEM specification for these ARRMA vehicles. Whilst other tooth counts (17T, 19T, 23T, 24T, 25T) are available and will technically fit a 3.2mm bore, changing the tooth count alters your final drive ratio, affecting acceleration versus top speed. The 18T is optimised for balanced performance across the full throttle envelope.
- What is the difference between MOD 0.5 and other gear pitch standards? — MOD (Module) 0.5 refers to the gear pitch, which determines tooth size and spacing. MOD 0.5 gears have teeth that are proportionally sized to mesh smoothly with other MOD 0.5 components. If you use an incorrect pitch (such as MOD 1.0 or MOD 0.8), the gears will not engage properly, resulting in poor performance, noise, and potential damage to both the pinion and spur gear.
- Is installation difficult? — Installation is straightforward and requires only basic tools. Simply remove your existing pinion gear from the motor shaft using the M3 set screw hole (typically with a 2.5mm hex key), slide the new 18T pinion gear onto your 3.2mm motor shaft, align it with the spur gear, and secure it with the supplied M3 x 4mm set screw. Most RC enthusiasts can complete this job in minutes without specialist knowledge.
- Will this work with non-ARRMA vehicles? — Whilst this pinion gear features standard MOD 0.5 specifications and a 3.2mm bore that might physically fit other RC vehicles using the same specifications, it is specifically engineered for ARRMA models and we recommend fitting only OEM or equivalent-quality replacement parts designed for your specific RC vehicle brand and model to ensure optimal performance and reliability.
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 18T MOD 0.5 CNC 3.2mm Bore Z-ARA-2031 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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