B-MAX4 Drive Gear Upgrade for Tuning BM-504 by Yokomo  [BM-504]

Drive gear for tuning and setup changes on B-MAX4

The Yokomo BM-504 drive gear with header card is supplied as a pair to support tuning-related part swaps on the B-MAX4 input shaft. This accessory is handy for drivers who change setups or perform quick adjustments between runs.

Placed on the input shaft, the gear transfers rotation through the gearbox train; the header card aids identification when managing multiple spares. Installation involves standard gearbox access to remove the old gear and press or slide the new gear onto the shaft, taking care with alignment and original shim placement.

In tuning contexts, the BM-504 is used to replace worn components or to maintain a matched set for consistent performance during setup trials and track testing.