Kit Cylinder and Crankshaft Italkit 73cc 40mm stroke Derbi Variant Start 3

The Cylinder and crankshaft kit from the Italkit brand, 73cc with a 40mm stroke, is a racing set developed for engine conversion on the Derbi Variant Start 3. This aluminum engine kit increases the engine's usable displacement thanks to its 48mm diameter, providing a direct increase in the moped's power and thrust.

The combined pairing of the Cylinder and the crankshaft in the same kit ensures exact mechanical compatibility in the crankcase. The Cylinder features a 2-piece modular cylinder head (cover and head insert), a configuration that helps improve heat dissipation in the combustion chamber. Meanwhile, the racing crankshaft with an original 40mm stroke and 12mm pin is prepared to withstand the increase in revs, reducing vibrations and providing stability to the Start 3 crankcase assembly.

The 48mm diameter piston incorporates 2 Piston rings that ensure consistent compression sealing, reducing premature wear. The kit includes the necessary gasket set to achieve an airtight assembly during installation.

Technical characteristics

• Kit reference: K.12.574.G
• Displacement: 73cc
• Piston diameter: Ø48 mm
• Stroke: 40 mm (original stroke)
• Piston pin: Ø12 mm
• Piston rings: 2 Piston rings
• Cylinder head: 2-piece modular (cover + head insert)
• Cylinder reference: CI.12.573.G
• Crankshaft reference: CB.12.5 (Competition)
• Gasket set reference: VJ.12.11

Compatible models

DERBI

• Variant Start 3 (with Start 3 crankcase)