Overview
The Hot Racing 21T 0.5 Mod Hardened Steel Pinion Gear gives you a precise, durable upgrade option for fine-tuning your 0.5 module RC drivetrain. CNC-machined from hardened steel and finished with a black protective coating, this 21-tooth pinion combines strength, precision, and a balanced gear ratio that splits the difference between acceleration and top-end speed.
The 1/8-inch (3.2mm) bore is purpose-sized for motors with a 3.2mm output shaft — including the Hot Racing CSG182R08 — and it pairs cleanly with any 0.5 Mod spur gear. A perfect choice when you want a slight gearing increase from a 19T or 20T without jumping all the way to 22T.
Key Features
- Hardened steel construction with blackened finish
- 0.5 module (Mod) tooth profile
- 21-tooth count — balanced acceleration and top speed
- 1/8-inch (3.2mm) bore — fits 3.2mm motor shafts
- Includes 3mm set screw for secure mounting
Performance Benefits
- Stronger and more durable than soft stock pinions
- Precision-cut teeth for smoother gear mesh
- Modest top-speed increase over 19T/20T setups
- Long service life under demanding drivetrain loads
Usage Notes
Designed for use with motors having a 3.2mm (1/8") output shaft, including the Hot Racing CSG182R08. Confirm spur gear pitch is 0.5 Mod before installing. Apply removable thread-locker to the set screw and verify gear mesh by hand before running.
Technical Specs
- Material: Hardened steel, blackened finish
- Number of Teeth: 21
- Bore Diameter: 1/8 inch (3.2mm)
- Gear Pitch: 0.5 Mod
- Length: 0.35 in (8.9mm)
- Tooth Face Width: 0.20 in (5mm)
- Hub Outer Diameter: 0.32 in (8mm)
What's Included
- One (1) 21T 0.5 Mod pinion gear
- One (1) 3mm set screw
Fitment
- Hot Racing CSG182R08 motor and other motors with a 3.2mm (1/8") output shaft
- RC drivetrains using a 0.5 Mod spur gear
Summary
The Hot Racing 21T 0.5 Mod Hardened Steel Pinion Gear delivers durable, precision-cut performance in a perfectly balanced gear ratio. The right pinion when you want a touch more top-end without sacrificing punch.
