Polini Z26 Sixth Gear Primary Shaft Ø18 for AM6 Engines 202.1433

The Polini primary shaft sixth gear part number 202.1433 introduces a long-ratio Z26 sixth gear for Minarelli AM6 engines, providing a taller final ratio compared to the standard Z25 configuration.

Developed by Polini's Research & Development department, this gear allows high-performance engines to make better use of their power by lowering engine RPM at higher speeds while improving top-end performance in sixth gear.

It is the ideal upgrade for road, sport and racing engine builds where a taller sixth gear improves cruising comfort and overall transmission efficiency.

Manufactured from high-strength alloy steel, it provides excellent durability, precise gear engagement and outstanding reliability even under demanding riding conditions.

Compatibility:

• Minarelli AM6 engines
• Series 1 (V1) transmissions with solid output shaft
• Ø18 mm gear bore

Technical specifications:

• Polini part number: 202.1433
• Long-ratio sixth gear
• Teeth: Z26
• Bore diameter: Ø18 mm
• Primary shaft gear
• High-strength alloy steel
• Precision machined
• Genuine Polini product
• Made in Italy

Main features:

• Taller ratio than the standard Z25 gear
• Reduces engine RPM at high speed
• Improves top-end performance
• Smooth and precise gear engagement
• Ideal for tuned and racing engines
• Excellent wear resistance
• Premium Polini quality

⚠️ Important

AM6 transmissions are available in two different, non-interchangeable versions:

• Series 1 (V1): solid output shaft with M6 thread → compatible with Ø18 mm gear (this product).
• Series 2 (V2): hollow output shaft with M8 thread → requires the Ø20 mm version.

Before purchasing, always verify which transmission version is fitted to your motorcycle by comparing it with the original output shaft.