MMX Crank hub & capture plate | S55 | N55

Description

The MMR Performance One-Piece Crank Hub Fix is engineered to fully resolve the well-known crank hub issue found on BMW S55 and N55 engines. The factory three-piece crank hub relies on friction plates that can slip under load, causing engine timing to shift and potentially leading to severe engine damage.

MMR’s upgraded solution replaces the original multi-piece unit with a single-piece billet EN36 steel crank hub, heat-treated with case hardening for exceptional strength and durability. The one-piece design eliminates the possibility of friction plate slippage, significantly improving engine reliability even on tuned or high-power vehicles.

The kit can also be paired with an optional Capture Plate, which locks over the crank bolt head to prevent loosening from vibration, providing complete peace of mind for both standard and modified engines.

For most stock to Stage 1 tuned engines, the non-pinned version provides sufficient reliability, while high-power builds may benefit from the pinned version for maximum engine security.