Stage6 Cylinder Kit 70cc Racing MK2 12mm piston pin Minarelli horizontal LC (Yamaha Aerox / MBK Nitro).

The next generation of Stage6's acclaimed 70cc racing cylinder, completely redesigned to deliver superior performance straight out of the box. Engineered for 50cc scooters with Minarelli horizontal LC engines, including MBK Nitro and Yamaha Aerox models. 

The hard chrome-plated cylinder features a completely new transfer port layout — 6 ports instead of 5 — for improved cylinder filling and combustion efficiency. The domed piston with 0.8mm ring thickness optimizes power delivery and heat management. Enhanced thermal design includes a pentagonal exhaust port with internal cooling ribs, one-piece head with cast scavenging channels, and optimized port timings of 190°-130°.

Delivers 17–19 hp—2 to 3 hp more than the MK1—without additional modifications when paired with compatible components. Sufficient material thickness allows further tuning to exceed 20 hp. Among the most powerful 70cc kits available. Pair with a reinforced crankshaft, minimum 21mm carburetor, and racing exhaust to unlock full potential.

Clean the engine before assembly and inspect all components. Install a fresh spark plug and small-end bearing. Adjust carburetor settings as needed. Maintain squish clearance between 0.75–0.85mm. Run in for approximately 300 km using a 1:33 fuel mixture. 

Important Notes : Original exhausts are incompatible. Temperature sensor (including thread) must not exceed 18mm to avoid contact with the cylinder head.

Not homologated in some countries.