Yokomo BM-S116TA Tapered X-Shock Piston for B-MAX4  [BM-S116TA]

Fine-tune shock balance with an asymmetric piston

This optional X-shock tapered piston is designed to change the damping balance between extension and compression by making one side of the piston tapered. The asymmetric profile gives tuners a simple mechanical way to bias shock behavior without changing oil viscosity or spring rates.

Pay attention to orientation: fitting the tapered face up on front dampers increases front load transfer during braking, while fitting it down on rear dampers reduces the chance of rear breakaway as the car rolls. The piston features six ports in a 1.1mm layout, and a 1.0mm variant (BM-S106T?400) is mentioned as an alternative in the source.

Introduce this piston into setups gradually—replace one piston, run tests, and record results to see which orientation corrects understeer or oversteer. It is an RC shock piston intended solely for tuning use.