This 48-tooth Delrin main (spur) gear is supplied as a single unit for use with the HPI Savage 21 platform. Manufactured as a Delrin component, it is presented for reduction of friction and controlled wear characteristics while remaining a neutral drivetrain replacement part.
Service and fitment follow established Savage 21 gearbox procedures: remove the existing main gear assembly, inspect mating gear teeth and bearing condition, and install the replacement gear while achieving correct mesh. Verify backlash and alignment using standard measurement practices and avoid altering other drivetrain components during fitment.
Functionally a direct replacement, the Delrin spur retains stock ratios unless a different tooth count is selected. Expect differences in acoustic signature and run smoothness when compared with metal gears; monitor break-in and recheck mesh and bearing play after initial operation.