Bell Mouth / Trumpet Polini D.55,5 blue

Bell mouth

Intake funnels or bell mouths are usually made of metal and are conically shaped to create a venturi effect. Bell mouths are mounted on the intake of the carburetor and serve the following purposes:

Racing bellmouth

In racing, carb bell mouths are used without air filters to let in as much fresh air as possible and reintroduce it into the engine. The responsiveness of the engine is also increased by the Venturi effect. However, the absence of the air filter exposes the engine to dirt and foreign bodies. In addition, it is usually necessary to install a large carburetor jet.

Bell mouth with grill

Intake cones with grille are used as an alternative to the original air filter or airbox when there is a lack of space or when the carburetor needs to be changed. They are mainly used on 50cc motorcycles with PWK carburetor, where there is often not enough space for an air filter.

Intake funnel for air filter

Intake funnels can also be used as a reducer or adapter for a pod air filter. This way the filter can keep the air clean and you can take advantage of the venturi effect.