Polini Motori has designed this crankcase to increase the power of your engine. The charters are supplied in three versions according to the type of cyclomotor (see technical file). This crankcase can be used to assemble original cylinders, as well as improved cylinders: piston Ø 41-43-46. With the new crankcase, it is not necessary to modify the connecting rod, since the suction valve has a larger advance. However, if you already have a reinforced crankcase (drawing A), it is possible to assemble it equally, since it will not compromise the maximum power of the engine, but it will improve the power at low revolutions. To mount the new charters, you have to disassemble the motor block of the chassis, disassemble the entire engine and carefully clean all the pieces that must be reused, incl.
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