Kyosho Mini-Z MR-02 MR-015 Titanium Differential Shaft KZ-05 by 3Racing  [KZ-05]

The KZ-05 titanium differential shaft is an aftermarket replacement part for Kyosho Mini-Z differentials, compatible with MR-02 (MM/RM) and MR-015 assemblies when the OEM shaft footprint matches. It offers a lightweight alternative to common steel shafts.

Purpose in the drivetrain: the shaft reduces rotating mass and helps preserve precise gear alignment under rapid throttle or steering inputs. On micro race cars this tends to produce sharper responses and more predictable transient handling.

Fitting instructions: access the differential by removing the gearbox cover and separate the differential housing. Transfer the internal components and seat the KZ-05 titanium shaft in place of the original. Reassemble and confirm a smooth freely rotating differential and correct gear mesh.

Tuning approach: consider this part as a subtle performance tweak. Combine it with tyre, gearing and suspension changes to dial in better turn-in and throttle recovery for short, technical layouts.