Piston - EGIG PERFORMANCE Ø65mm, Gray Cast Iron 170 ccm - Vespa PV125, ET3 125, PK125 - Short Version - Cat. A

EGIG Performance Piston, Ø65 mm – Short Version for EGIG 170 Gray Cast Iron Cylinder

Genuine EGIG Performance replacement piston with a 51 mm stroke length for the 170 cm³ gray cast iron cylinder of Vespa Smallframe models. The short piston version corresponds to the original design of the EGIG 170 cylinder kit and allows for easy installation without having to drill out the engine housing when using the intended engine configuration.

Original design for plug-and-play

The EGIG 170 cylinder concept was specifically developed for the simplest possible installation on Vespa small-frame engine cases. Despite the large 65 mm bore, the cylinder can be used in combination with the specified crankshaft—which has a 51 mm stroke and 115 mm connecting rod length—without having to ream the crankcase opening.

The key to this is the short piston design: at bottom dead center, the piston skirt does not extend into the standard, smaller crankcase opening. This preserves the simple installation characteristic of the EGIG 170 design.

The 51-mm version is therefore particularly suitable for replacing a worn or damaged original piston, as well as for engine builds where the engine block should remain as unchanged as possible.

Product Features

• Original short-stroke piston version of the EGIG 170 cylinder kit
• 51 mm piston length for maximum ease of installation
• Ø 65 mm nominal diameter
• Available in four size classes to match the cylinder bore
• Plug-and-play when using the specified crankshaft geometry
• No enlargement of the housing opening for the piston skirt required
• Complete with piston rings, piston pins, and retaining clips

Available piston size classes

• Size A: 64.87 mm
• Dimension B: 64.88 mm
• Dimension C: 64.89 mm
• Dimension D: 64.90 mm

Important: The appropriate piston size class must be selected based on the actual cylinder bore and the specified piston clearance. A larger piston is not automatically the better choice.

Package Contents

• 1 × piston, 51 mm long
• 2 × piston rings
• 2 × piston pin retaining clips
• 1 × piston pin

Fits

• Vespa PV 125 / Primavera
• Vespa 125 ET3
• Vespa PK 125

Requires the use of the matching EGIG Performance 170 cm³ gray cast iron cylinder.

Installation Note

The “plug-and-play” feature applies to the specified EGIG 170 engine configuration with a 51 mm stroke and 115 mm connecting rod length. If the crankshaft, stroke, or connecting rod length differs, check that the piston moves freely.

Before installation, check the cylinder bore, piston clearance, and piston ring end clearance.

Alternative: Long-stroke piston version

For engine configurations where minimizing piston tilt and ensuring smoother mechanical operation are priorities, the EGIG piston is also available in a version extended by 5 mm. This provides greater lateral support but may require machining of the engine block.

Conclusion

The short 51-mm version is the right choice for anyone who wants to retain the original EGIG 170 concept with its plug-and-play features. It offers the original piston geometry and, with the right setup, allows for installation without extensive housing machining.