Stage6 is renowned for developing high-performance tuning components and continuously pushing the limits of engine performance. Expanding its range of performance parts, the brand has introduced a powerful cylinder kit designed specifically for 50cc supermotos and geared motorcycles.

The Stage6 Big Racing 77cc cylinder kit for Minarelli AM6 engines combines innovative engineering, high-quality materials and impressive performance.

Developed in close collaboration with the experts at MXS Racing, the Big Racing cylinder benefits from extensive experience in the world of geared 50cc motorcycles, combined with Stage6's own technical expertise. The result is a carefully engineered and highly advanced tuning cylinder designed to deliver outstanding performance.

Despite its discreet appearance, the Big Racing is a genuine big-bore aluminium cylinder, not simply a modified or enlarged version of a standard cylinder. Designed from the ground up, it features precisely matched transfer ports and an oversized exhaust port to ensure efficient gas flow and maximise power output.

Easy installation: The cylinder can be installed without machining or modifying the engine crankcase. The squish clearance is optimised for the specific engine type.

Outstanding performance: The cylinder has achieved impressive results of up to 23 hp and 13 Nm on a P4 dynamometer using a standard test configuration consisting of a 24 mm carburettor, original ignition system and racing exhaust.

Strength and reliability: Carefully engineered port timings (190° exhaust / 125° transfer), generous cooling capacity and a high-quality Vertex piston ensure excellent durability when the engine is correctly configured and tuned.

With a 50 mm piston diameter, the cylinder offers a displacement of 77cc, making it unsuitable for public-road use where 50cc homologation is required.

For reliable operation, Stage6 recommends using a reinforced crankshaft with the original standard stroke.

Interestingly, the cylinder retains the external appearance of the original 50cc cylinder, including the stamped 49cc marking. However, don't be fooled by its appearance – this is a genuine 77cc big-bore cylinder.

Installation tip : We recommend using extended cylinder head nuts to ensure proper tightening and secure installation of the cylinder head.

• 77cc aluminium cylinder with 5 transfer ports and bridged exhaust port
• Vertex single-ring piston (50 mm)
• High-compression, one-piece aluminium cylinder head
• Complete gasket set, including cylinder base and head gaskets