13mm Shock Pistons BK Design with Dimples (2) (JCO5205)

13mm BK Design Shock Pistons with Dimples are precision-machined Delrin pistons designed for 13mm shock bodies. The dimples on the top let drivers fine-tune grip for dirt-track conditions and mid-motor setups, delivering smoother, more predictable handling with enhanced traction.

Inside the piston, the BK channel increases the oil volume inside the shock, creating an extra chamber that helps stabilize damping during compression and rebound. The dual-channel design directs fluid through two paths while the disturbance stays immersed in oil, contributing to more consistent performance and better coordination with the track surface. The top dimples provide tunable reference points for different tracks, and a common dirt-start setup is front: two 1.7mm holes and one 1.8mm hole with 30wt oil; rear: two 2.0mm holes and one 1.0mm hole with 27.5wt oil, offering a practical baseline to dial in grip across varying conditions.