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Engine case with diaphragm intake compatible with your Vespa P 125X, PX 125 Lusso, PX 125 MY, P 150X, and PX 150 MY scooters.
This completely redesigned housing is designed to replace the original Piaggio engine housing and remains compatible with original Vespa components. Instead of the classic rotary valve intake, this engine block uses a flat diaphragm system. This helps resolve issues caused by worn intake sealing surfaces and allows for the installation of a racing diaphragm block with a 28/30 mm carburetor. The standard SI carburetor can still be mounted on the housing, including the version with separate lubrication.
The housing halves are numbered in pairs and machined together to ensure that the bearings and sealing surfaces fit together perfectly. The flow patterns of the crankcase and overflow ports have been optimized using CFD simulation. The swingarm, the transmission area, the shock absorber mount, and the cylinder base are reinforced, providing a stable foundation for powerful street engines as well as racing setups.
On the clutch side, a ground steel flange supports the bearing. This design also prevents the shaft seal (colloquially known as a Simmerring) from migrating out of position. On the ignition side, a larger bearing measuring 25x52x15 mm is used. M8 hex screws replace the traditional M7 through-bolts and make the housing assembly stiffer. The motor housing is made of heat-treated Al Si10 Mg T6 aluminum alloy and is designed to accommodate an electric starter. The offset filler neck for the transmission oil increases the oil capacity and improves lubrication in the transmission.
The silent blocks are already pre-installed. In addition to the two housing halves, the package includes all small parts required for assembly. The shaft seals and bearings are also included.
You can find the matching clutch cover and cylinders in the accessories section.
A quality product from the Italian manufacturer Polini.
| Manufacturer | Polini |
| Material | Cast aluminum |
| Ignition type | Electronic |
| Width | 320 mm |
| Total length | 420 mm |
| Height | 345 mm |
| Vespa | Vespa PX, T5, Cosa - P125X · VNX1T · 1977 - 1982 (PX alt) Aussenverschluss , P125X · VNX2T · 1981 - 1984 (PX alt) Innenverschluss , PX125 E · VNX2T · 1982 - 1993 / Lusso / Arcobaleno , PX125 · VNX2T · 1993 - 1996 Classic , PX125 · VNX2T · 1997 - 1999 (Disc) , PX125 · ZAPM471 · 2001 MY Katalysator (Millenium) , P150X · VLX1T · 1978 - 1993 , PX150 · ZAPM742 · 2001 MY Katalysator (Millenium) |
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Malossi 63 mm Cylinder Kit "MHR 177" | Vespa Large Frame
Manufacturer: Malossi · Material: Aluminum · Displacement: 177 ccm · Crankshaft stroke: 57 mm · Ø cylinder neck: 67 mm · Ø Outlet outside: 37 mm · Ø outlet inside: 33.9 mm · Ø piston pin (B): 15 mm · Outlet type: straight · Hole spacing outlet: 55 mm · Number of fixing points: 4 pcs · Decompressor: No · Camouflaged: No · Area of application: Tuning
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