AIMROCK 5-Pack 48P RC Motor Pinion Gears (13T-17T) for 1/10 Scale Cars, Boats & Planes – Hardened Steel

This AIMROCK 5-pack includes five 48-pitch pinion gears with 13, 14, 15, 16, and 17 teeth, all fitted with a 3.175mm (1/8 inch) bore for 1/10 scale RC cars, boats, and planes that use a 3.175mm motor shaft. The gears are machined from hardened steel and come with grub screws and a steel hex key, giving you the flexibility to adjust your vehicle’s speed and torque by swapping pinion sizes.

Pitch and Material Details

These are 48-pitch pinion gears, meaning they have 48 teeth per inch of pitch diameter. They are designed to mesh only with 48-pitch spur gears. The hardened steel construction is intended for use with steel spur gears; using them with plastic or aluminum spur gears can cause damage to the spur gear, as noted by the manufacturer. Hardened steel offers good wear resistance for RC drivetrains.

Choosing the Right Teeth Count

The set provides five tooth options: 13, 14, 15, 16, and 17 teeth. A smaller tooth count (like 13T) gives more torque and lower top speed, while a larger tooth count (like 17T) increases top speed but reduces torque. Having all five sizes lets you experiment with different gear ratios to match your driving conditions or battery voltage.

What's in the Box

• 5 × RC pinion gears (one each of 13T, 14T, 15T, 16T, 17T)
• 5 × RC grub screws (set screws)
• 1 × steel hex key (for securing the grub screws)

Each gear and screw is separate; you install the grub screw through the threaded hole in the gear to lock it onto the motor shaft.

Installation Notes

Before installing, verify that your motor shaft diameter is 3.175mm (1/8 inch) and that your spur gear is 48-pitch and made of steel. Use the included hex key to tighten the grub screw securely against the shaft’s flat spot (if present) or against the shaft itself. Avoid over-tightening, as that can strip the screw or distort the gear.

Common Questions About This Pinion Gear Set

Can I use these pinion gears with plastic or aluminum spur gears?

The manufacturer warns against using these hardened steel pinion gears with plastic or aluminum spur gears because the harder pinion can wear down or damage softer spur gears. They are intended only for steel spur gears.

What vehicles are these gears compatible with?

Any RC car, boat, or plane that uses a 3.175mm motor shaft and a 48-pitch spur gear. Many 1/10 scale touring cars, buggies, and trucks fit this combination. Always check your vehicle’s spur gear pitch and motor shaft diameter before ordering.

How do I install a pinion gear?

Slide the gear onto the motor shaft, align the grub screw hole with the shaft’s flat or a solid section, insert the grub screw, and tighten with the included hex key. Make sure the gear is fully seated and centered before running the motor.