Stage6 Sport Pro MK2 70cc Cylinder Kit – Piaggio LC (NRG / Runner / and others)

The Stage6 Sport Pro MK2 is the successor to the legendary MK1 cylinder kit — a favorite among scooter tuners. Stage6 has completely re-engineered this version, bringing both improved power and durability for Piaggio LC engines such as those found in the Piaggio NRG and Gilera Runner.

Design & Construction

The MK2 cylinder features a complete redesign with 6 transfer ports (up from 5 on the MK1) for optimized cylinder filling. The oval exhaust port has been refined for smoother gas flow, while the pentagon-inspired design takes cues from the high-end R/T series.
The one-piece cylinder head includes integrated scavenging channels for superior heat dissipation. Inside, a domed R/T-style piston with a 0.8 mm thin piston ring enhances performance and thermal stability.

Performance

With the proper setup, the MK2 delivers 2–3 hp more than the previous version — achieving an impressive 14–17 hp output with compatible tuning components. It offers exceptional strength, power, and reliability, setting a new benchmark in the 70cc sport cylinder category.

Recommended setup for optimal performance :

• Reinforced crankshaft

• Minimum 19mm carburetor

• Sport or racing exhaust system

Installation & Setup Tips :

• Thoroughly clean the engine before installation and inspect all components.

• Use a new spark plug and small end bearing.

• Adjust carburetor settings if needed.

• Squish clearance: 0.75–0.85 mm

• Break-in period: approx. 300 km using a 1:33 oil mixture

Important notes:

• Original exhaust systems cannot be used with this cylinder.

• Temperature sensor (including thread) must not exceed 18 mm in length to prevent contact with the cylinder head.

• Not homologated for road use in some countries.

Kit Includes:

• Aluminum cylinder (47.6 mm bore)

• Single-ring piston with 12 mm piston pin

• One-piece cylinder head

• Complete gasket set