The WBW FlowMax Exhaust Plate corrects a restriction in the Wetbike exhaust system between the engine outlet and the expansion chamber diffuser.
In two-stroke exhaust systems, maintaining smooth, even flow from the engine to the diffuser is critical for proper expansion chamber function. Disruptions in this transition—such as abrupt direction changes or mismatched flow areas—can introduce turbulence and reduce exhaust efficiency.
The stock banana plate provides approximately 2.2 in² of flow area, creating a restriction relative to the diffuser entrance.
The FlowMax plate increases this transition area to approximately 2.9 in² while maintaining a even cross section flow path from the engine to the pipe.
Unlike spacer-based modifications, this design preserves smooth exhaust flow and adequate sealing surfaces.
Additional material is intentionally left in the transition area, allowing builders to port match the plate up to 3.14 in² to support modified engines and larger diffuser openings.
The result is a properly engineered exhaust transition that improves diffuser feed and supports increased engine performance.
Below chart of cross sectional areas:
Below is a visual respesentation of the flow path as modeled in the flowmax plate with a 1.9″ diffuser entrance
Below is the flowmax plate with a cross section cut from the flow path with a 2″ ported diffuser.
