Vespa Primavera 125 [1967-1975] - crankshaft with pin ø 15, rod 105, stroke 51 mm and cone ø 20 for engines with reed valve

MALOSSI crankshaft for Vespa Primavera 125 with membrane inlet

The MALOSSI crankshaft is intended for the Vespa Primavera 125 from the entire 1967-1975 model year range. It was developed for engines that have been converted to a diaphragm or reed valve inlet instead of the original rotary valve.

Designed construction

The solid crankshaft combines a design tailored to the diaphragm inlet with a circular mass structure. Tungsten inserts support a balanced design. On the gearbox side, a specially designed bevel makes it easier to absorb fresh gas under the oil pan.

The piston rod in “Viper Head” shape is designed for low weight with the required rigidity. The design of the thread on the gearbox side and the position of the key were also taken into account in the design. The scope of delivery includes special nuts that are designed for the reinforced thread.

Technical data

• Version: crankshaft with pin
• Pin: ø 15
• Bar length: 105
• Stroke: 51mm
• Cone: ø 20
• Material: reinforced aviation grade steel
• Production: cast in vacuum

Vehicle assignment and installation instructions

Suitable for Vespa Primavera 125, built between 1967 and 1975. For assembly, the crankshaft seat on the ignition side of the engine housing must be drilled to Ø 87. A spacer and ball bearing are required and sold separately.

The product is intended exclusively for racing in designated locations in accordance with the regulations of the relevant sports authorities. Improper use is excluded.