ARA311204 Pinion Gear 18T MOD 0.5 CNC 2.3mm Bore

The ARRMA® ARA311204 is a CNC-machined 18-tooth MOD 0.5 pinion gear with a 2.3mm bore, designed for ARRMA vehicles running a MOD 0.5 drivetrain. CNC machining ensures precise tooth geometry and consistent mesh with the spur gear, delivering smooth, efficient power transfer and reducing drivetrain wear compared to cast or stamped alternatives. The 2.3mm bore fits the motor shaft sizes common in ARRMA’s smaller-scale platforms. Whether you’re replacing a worn pinion or tuning your gear ratio for more speed or torque, the ARA311204 gives you a precision-fit, durable replacement that installs correctly and performs consistently.

Key Features

• Part Number: ARA311204
• ARRMA CNC-machined pinion gear
• Teeth: 18T
• Module: MOD 0.5
• Bore: 2.3mm
• CNC machined for precise tooth geometry and consistent spur gear mesh

Compatibility

• ARRMA vehicles with MOD 0.5 drivetrain and 2.3mm motor shaft — verify fitment with your model’s parts diagram

Benefits

• CNC machining delivers precise tooth geometry for smooth, efficient power transfer
• Consistent spur gear mesh reduces drivetrain wear and noise
• 2.3mm bore fits motor shaft sizes common in ARRMA small-scale platforms
• Direct OEM replacement — correct fit, correct module, no modifications needed
• Use to replace a worn pinion or tune gear ratio for speed or torque

Quick Take

Need a precise, durable pinion for your MOD 0.5 ARRMA drivetrain? The ARA311204 CNC 18T pinion meshes cleanly with your spur gear and fits your 2.3mm motor shaft — bolt it on and get back to running.