Crankshaft Polini P.R.E 4 c.39.3mm Piaggio / Minarelli scooter 50 2T

Polini Crankshaft P.R.E 4 stroke 39.3mm for Piaggio / Minarelli 50 2-Stroke scooter.

If you are building a high-level engine such as the Polini P.R.E., you need a crankshaft that is up to the task. This 39.3mm stroke model is ideal if you want your engine to withstand maximum track stress without risk of breakage. It is an engineered component designed to handle extremely high rotational speeds and transmit all power to the transmission in a balanced manner.

When you move from a basic build to a racing one, the stock crankshaft becomes the weak point. The Polini P.R.E. is manufactured from high-strength materials and a reinforced 90mm connecting rod that ensures it will not bend or break under pressure. Being perfectly balanced, you will notice that the engine vibrates much less and revs up with astonishing ease, allowing you to extract every horsepower from your cylinder.

Technical specifications

• Stroke: 39.3 mm.
• Connecting rod: 90 mm length, designed to reduce lateral forces on the piston.
• Wrist pin: Compatible with 13 mm wrist pin pistons.
• Balancing: Performed with tungsten inserts for maximum stability at high RPM.
• Recommended for installation with the Cylinder Polini P.R.E 4 140.0239

NOTE: It can be installed with the original Piaggio crankcase or with Malossi RC or C-ONE and Polini crankcases.

¡Attention! To install this crankshaft, it is essential to use high-speed bearings (C4 type) and a racing-quality needle bearing to ensure lubrication.