The Dell'orto SI carburetor series features a cylindrical venturi duct. 

This very simple shape to produce during manufacturing, however, performs less well in operation compared to carburetors with a conical frustum-shaped venturi duct, as it generates turbulence.

The venturi cone made by Sil-tech PERFORMANCE is designed to address this issue.
Thanks to many CFD (computational fluid dynamics) simulations conducted to derive the best cone profile and various tests performed on the respective motorcycles, a solution has been reached that allows solving the problem of inlet turbulence by developing a specific object for each application.

With the application of a venturi cone, the flow enters less turbulently, achieving a greater air flow entering the engine and an improvement in performance across the entire RPM range.

Designed to occupy as little volume as possible, ensuring optimal operation within the original carburetor box.

TO INSTALL THIS COMPONENT, IT IS NECESSARY TO REMOVE THE ORIGINAL FILTER ELEMENT. 

Material: sintered NYLON PA12, ensures chemical resistance to solvents (gasoline and other hydrocarbons) and oils.

It has excellent

Gasket for the carburetor box (WITHOUT MIXER) made of
sintered polymer, it is flexible but with excellent mechanical and chemical resistance.
It has the same shape as the box to avoid joints and ensure optimal sealing.

The Dell'orto SI carburetor series features a cylindrical venturi tube. 

This shape, very simple to produce, however, is less efficient in operation compared to carburetors with a conical venturi tube, as it generates turbulence.

The venturi cone made by Sil-tech PERFORMANCE is designed to overcome this problem.
Thanks to many CFD (computational fluid dynamics) simulations conducted to derive the best cone profile and various tests performed on the related motorcycles, a solution has been reached that allows solving the turbulence problem at the inlet by developing a specific object for each application.

With the application of a venturi cone, the flow enters less turbulently, obtaining a greater air flow entering the engine and an improvement in performance across the entire RPM range.

Designed to occupy as little volume as possible, ensuring optimal operation within the original carburetor box.

TO INSTALL THE FOLLOWING COMPONENT, IT IS NECESSARY TO REMOVE THE ORIGINAL FILTER ELEMENT.

Material: Sintered NYLON PA12, ensures chemical resistance to solvents (gasoline and other hydrocarbons) and oils.

It has excellent mechanical properties

For carburetors type SI

Minimum jet-->38
Maximum jet-->84

Race
Ø 26 mm
engine connection: 36 mm
air filter connection: 49mm
main jet 128
secondary jet 42
mixer tube HE265
needle 48
metal casing, polished carburetor valve

Minimum flow-->36

Maximum flow-->104

Elastic attack with 35 mm graft

Diameter: 23 mm
Ref.Orig: 134125.5

Notes: for carburetors 19:19

Suitable for turned cylinder.

Dellorto SHBC 19-19 Original type
Settings--> Main Jet 74  Idle Jet 45  Starter 60

1L Package
2T

Synthetic-based lubricant with very high performance specific for highly stressed 2-stroke engines.
Elegant and vintage 1L tin packaging.

High-performance mineral lubricant specific for 2-stroke engines.
Elegant and vintage 1L tin packaging.

Fully synthetic lubricant for all two-stroke engines, even highly stressed ones. Dual-purpose product also suitable for separate lubricators of modern scooters.

Performance levels:
JASO FD, ISO-L-EGD, API TC capable.

1L package

Recalculated and solidly derived cornet, specifically designed to improve engine performance, especially at low revs, thanks to the "Venturi effect".

Triangular section

Included: Rubber sleeve, clamps, and gasket

Galvanized

Kit composed of:

- Cable grommets and engine caps

- Grips

- Frame seals and bellows

- Stand feet

- Tank seals

Rubber quality guaranteed for most of the kit components by ARIETE (leader in the production of rubber parts for Vespa)

Color black

Filter size: 80x63mm

Mount diameter: 35mm

Thanks to the various adjustments and two different mounting kits, you can install it on all carburetors on the market and, with an almost original throttle grip stroke, manage from the classic 24 to larger carburetors like the vhsb39. In addition to keeping the handlebar of your Vespa original, you can allow the sheath to take a much more linear path and at the same time have a quick release of your carburetor. The kit will include everything needed to mount it on both the classic phbh or phbl, and for the vhsb with a plastic cap as well as for the vhsb racing or vhsh with an aluminum cap.