A set of strengthened engine casings for Vespa Largeframe models. They provide a solid basis with potential for solidly road-tuned everyday motors through to high-tech racing machines.
The spine of any engine, especially with Vespas, is provided by its casings. Although they only have a secondary function as far as providing power is concerned, no motor can be stronger than the construction of its casings allows. The load carrying capacity of engine casings decides the amount of power that can be safely transmitted through the gearbox to the rear wheel and ultimately, the road. The dimensions of the engine casings determines the size of the peripheral components that can be effectively included in the set up and with it the power they can together provide. The construction of the crankcase and the cylinder base gasket surface area are an indication of the limits of the potential performance envelope.
- Plenty of space for modern, powerful tuning components.
- A massive, stable and elaborately balanced crankshaft
- Very sturdy case, manufactured with extremely tight tolerances
The SIP-BFA engine casings redefine the boundaries of tuning Largeframe Vespas. Firstly, they are provided with an impressive framework upon which muscled components can flex their power and a plug and play capacity of a whopping 306cc is enabled! The potential power output has now been raised beyond the 60PS mark. The gearbox, clutch and crankshaft are now held sturdily and exactly in position.
In spite of its improved overall dimensioning the basic, essential form of these engine casings is identical to that of the PIAGGIO originals, including identical distancing between the gearbox shafts. All of the gearbox components are compatible with engine projects based on the original engine casings. The area surrounding the original basic form has been expanded due to the design of these BFA produced engine casings. There is now adequate elbow room for their larger crankshaft, more capable of withstanding the increased performance, while also providing an even more smoother running motor due to its larger mass of 3.5Kg.
The right space for every cylinder
There is also increased room for the positioning of cylinders, facilitating simpler integration of any established Vespa tuning cylinder kits. They provide an excellent basis for a much tougher engine and swing-arm set up with, for example, the fitting of a MALOSSI 221cc cylinder. Another advantage of this increase in area is the potential for countless possibilities to enlarge the cubic capacity and assimilate many exotic types of cylinder, with even higher possible levels of power output. Even unusual and extravagant transfer port layouts can be catered for! The ultimate plug and play solution is represented by the BFA 306cc cylinder with its almost inexhaustible reserves of potential performance. These engine casings and components were designed to complement it ideally and due to its compatibility with the air-cooling feature of Vespas, very simply further modified and/or tuned.
An especially advantageous aspect of the construction of these engines is the massive design of the output shafts mountings. The 70mm wide inlet port is located directly beneath the base of the cylinder and is spread sideways over both crankcase halves. The original 24mm SI carburettor can no longer be used but the Dell'Orto PHS carburettors, available with a diameter of between 28 and 39.5mm, exploit the space provided ideally. They are also more capable of providing a more reliable supply of fuel than the original items. The fuel supply to the carburettor itself can be additionally secured through the use of the fuel-pump vacuum supply connection, already integrated as standard into the design of
