The Auxiliary (or Secondary) Venturi is designed to accelerate airflow through the carburetor throat. This helps pull fuel from the float bowl at low engine speeds, as well as contributing to off-idle throttle response. The 5.0mm size is quite large, recommended for large engines (500cc or more per cylinder, assuming one cylinder per throat). Two required per carburetor; sold individually.
This part fits the Weber 48, 50, or 55 DCO/SP (made in Spain) only. It does not fit any older DCOE (Made in Italy) models.
Please note, the 5.0mm size is the only size currently available from Weber.
Note: Fits genuine Weber (made in Italy or made in Spain) carburetors only! Does not fit most copies, Asian knock-offs, or work-alikes.