HPI Baja 18T Steel Pinion Replacement SBJ018T by GPM  [SBJ018T]

Pinion replacement for HPI Baja models

The SBJ018T is an aftermarket 18-tooth steel pinion supplied as a direct replacement for HPI Baja drivetrains. Its steel composition focuses on long service life and stable tooth engagement to keep power flowing efficiently between motor and spur gear during off-road running.

Built for HPI Baja compatibility, this pinion works well for hobbyists who tune gear ratios for different surfaces or who maintain drivetrains regularly. The 18-tooth choice offers a middle ground between strong acceleration and useful top speed when paired correctly with the spur and motor.

Fitment tips: ensure correct mesh with the spur, confirm centre distance and motor shaft compatibility, and tighten set screws to the appropriate torque. Slowly rotate the drivetrain to inspect contact patterns and schedule routine checks for wear and runout to protect drivetrain components.

Opt for this steel 18T pinion when you need a robust replacement for HPI Baja drivetrains or when fine-tuning final drive ratios for performance adjustments.