MBX-5 going BL. Center diff question.

[Serum]

The problem is that stock nitro centerdiffs use steel spurs. The hardened pinions don't hold long on BL motors, that's the reason why everybody is exchanging them with plastic ones.

The inner gears of the mugen use 3.5mm shafts, over the normal 4mm shafts. the HB (which uses 4mm inner pins) is a 1:1 fit for the kyosho spurs. Since the kyosho spurs are fair cheap, it's easier/cheaper to use a HB diff with a kyosho spur rather than making an adapter to make a 51T ofna spur work. (the 51T ofna isn't a bolton, it requires an adapter)