The Polini crankcases have been redesigned for Vespa PX and are available in two versions: PX 125/150 and PX200 E. A successful combination where technical innovation and craftsmanship go hand in hand for efficient operation. A range of accessories that has been designed to offer maximum performance while ensuring compatibility with original components and maximum structural reliability.
Polini crankcases for Vespa PX in detail
Ready for performance, the Polini crankcases for Vespa PX represent a profound evolution of the technique of these models, keeping their historical tradition unchanged. Among its main technical characteristics we can highlight a revolutionary feeding system.
Switching from a traditional rotary valve system to a flat reed valve system eliminates carburetion problems related to stock valve sealing and improves engine response and overall performance. We also have the possibility of installing a set of competition reed valves with a 28/30 mm carburetor.
On the other hand, Polini crankcases for Vespa PX have advanced technical details that include, among others:
- Modification of the assembly to prevent the clutch side oil seal from coming off
- Ground steel flanges for bearing support on clutch side
- Enlarged ignition side bearing (25x52x15) for smoothness and durability
- M8 hex bolts for more rigid mounting, replacing traditional M7 through bolts
Likewise, both the shock absorber supports and the cylinder base are completely reinforced. There is also the possibility of installing electric start, while the gearbox oil filler cap has been relocated to increase lubrication capacity.
Regarding the mechanical and structural innovations presented by these Polini kits for Vespa PX, the Italian firm ensures that the crankcases are numbered and matched during machining, guaranteeing, in addition to perfect alignment of the bearings, maximum flatness of the contact surfaces.
Another notable detail would be the optimization of fluid dynamics through CFD (finite volume) simulations in the transfer ducts and pump casings, thus offering superior performance. In addition, Polini has worked on the redesign of the swingarm geometry through:
- FEM analysis for structural reinforcement
- Added internal ribs and overmolding to accommodate larger wheels
- Reinforced gearbox area around the wheel axle
In terms of quality of the material used in the Polini crankcases for Vespa PX, these are made of light aluminum alloy. Al Si10 Mg T6cast in shell molds and heat treated. This guarantees maximum mechanical resistance, as well as efficient thermal stability. Finally, it is worth mentioning the elimination of the central gasket and the increase in the contact surface between the crankcase halves.
This achieves better sealing and stability, even under high thermal expansion. Offered under two different references, the Polini crankcases for Vespa PX are available for both the PX 200 E model (818 euros + VAT) as for PX 125/150 variants (789 euros + VAT). For more information and details you can consult the brand’s official website.
