Polini EVO REED engine housing for your Piaggio Ciao, Si, Bravo and Grillo moped / moped.
Most important key points in the ¨overview:
- Intake tract:
The new edition of the legendary Evolution racing gear is used as standard with a supplied side inlet and 4-flap diaphragm. Polini recommends a 21 mm CP (not included) as the ideal carburetor. The air filter for this has been specially adapted to the new engine parts and the 21 mm carburettor.
The rear inlet can be used with a second carburettor if required. A cover plate for closing is included.
The space in the frame for the side intake is limited, but with our test frame, installation was possible without any adjustments. To do this, the engine is moved forwards and backwards in the slots of the frame in order to be able to fit the four screws of the inlet connector.
- Cylinder:
With the development of the EVO racing gearbox, a new 47 mm cylinder with four stud bolts was also introduced. The familiar overflow channels and the stud bolt hole pattern from the 43 mm cylinder and the previous 46 mm cylinders are also present in the new housing, which enables operation with these racing cylinders.
- Firing:
The racing case is designed for electronic ignitions. Conventional stators with one output for the light can be fitted without any adjustments. However, if stators with three consumer coils are used, adjustments to the housing are required for space reasons.
The Polini ignition (not included in the scope of delivery), which is also a new development, unfortunately does not fit into the tuning housing without adjustments. The cam outlined in the detailed picture must be milled off for this. Machining instructions are included.
If the Polini ignition is used in conjunction with a rotary valve crankshaft, an additional weight must be fitted to compensate for the resulting imbalance.
- Crankshaft:
If the gearbox is operated with the side inlet, it is recommended to use the Polini EVO REED full cheek crankshaft (not included in the scope of delivery).
Operation of the crankcase with a standard Piaggio crankshaft is possible and necessary if two carburetors are used.
In addition to the two reinforced C4 SKF ball bearings, the required shim washers and oil seal are also included in the scope of delivery of the crankcase.
The workmanship of the housing is fine. However, there are some small visible brows on the channels, for example, which should be smoothed out a little beforehand.