The Stage6 Sport Pro MKII 70cc Cylinder Kit is the evolution of the legendary MK1 — redesigned for more power, improved cooling, and higher durability. Ideal for Minarelli horizontal LC engines such as Yamaha Aerox and MBK Nitro.

Cylinder Design

Completely re-engineered, the MK2 features 6 transfer ports (instead of 5) for optimized cylinder filling and an improved oval exhaust port. Its pentagonal shape takes inspiration from the high-end Stage6 R/T series.
The one-piece cylinder head includes cast scavenging channels for better heat dissipation.
The domed piston with a 0.8 mm ring enhances performance and thermal stability, further improving reliability under high loads.

Performance

With 2–3 hp more than the MK1, the MK2 delivers 14–17 hp out of the box, and even more with further tuning.
This cylinder offers excellent power, torque, and durability, making it one of the top choices in the 70cc sport segment.

Recommended setup:

• Reinforced crankshaft
• Minimum 19 mm carburetor
• Sport or racing exhaust

Installation Notes

• Clean engine before installation
• Always use a new spark plug and small end bearing
• Adjust carburetor settings as needed
• Squish clearance: 0.75 – 0.85 mm
• Run-in period: approx. 300 km with 1:33 mixture

Attention:

• Original exhaust systems cannot be used.
• Temperature sensor (including thread) must not exceed 18 mm length, otherwise it may touch the cylinder head.
• WITHOUT HOMOLOGATION (in some countries).

Scope of Delivery

• Aluminium cylinder, Ø 47.6 mm bore
• 1-ring piston with 12 mm piston pin
• One-piece cylinder head
• Gasket set