18T 0.5M Motor Pinion MG318T/0.5M for 3.175mm Shafts by GPM  [MG318T/0.5M]

Pinion for compact RC drivetrains

This MG318T/0.5M motor gear is an RC-scale pinion made for motors specified to a 0.5mm module and a 3.175mm motor tooth diameter. Constructed from hardened 40Cr steel, it offers greater wear resistance than basic stock gears and keeps a consistent tooth profile under load to deliver predictable power transfer in small drivetrains.

The gear contains 18 teeth and a round motor bore sized for a 3.175mm motor tooth diameter, secured by two 3x3 set screws to hold position on the motor shaft. Before purchasing, confirm your motor shaft diameter, module, and required tooth count to make sure of correct fitment; only motors matching these dimensions should be used.

When fitting the pinion, check alignment with the spur gear, avoid excessive preload, and tighten the set screws enough to secure the gear without deforming the shaft; proper meshing reduces premature wear and keeps drivetrain efficiency high.