Box system developed in collaboration with W1R - WhiteOneRacing. Delivers rich torque from the bottom like a Proma "banana", revs out significantly further and achieves higher peak power. Two versions: Ø28 mm for short-stroke 75-112/115-130cc, Ø32 mm for 133 cc and larger. On conventional setups, >9,000 /min can be easily achieved.
Not suitable for PK "Automatica" (different engine/exhaust flow).