Stage6 BigRacing 88cc Cylinder Kit – Derbi Euro 3 / Euro 4

High-end big bore racing cylinder kit developed for Derbi Euro 3 and Euro 4 engines. Designed in collaboration with MXS Racing, this cylinder is built from the ground up as a true 88cc performance unit rather than a modified standard cylinder.

It features optimized port geometry, a bridged exhaust port, and high-quality components to deliver strong power output while maintaining reliability when properly set up.

Performance & design highlights :

• True “big bore” design (not a modified stock cylinder)
• Optimized transfer ports and bridged exhaust port for high flow
• Excellent cooling capacity
• High-performance layout with timing around 190° / 125°
• Tested output: up to ~23 hp with proper setup

Technical specifications :

• Displacement : 88cc
• Bore : 50 mm
• Stroke : 45 mm
• Connecting rod : 90 mm (long-stroke crank required)
• Material : Aluminium
• Exhaust : 32 mm bridged port
  Transfer ports: 5

Contents :

• 88cc aluminium cylinder
• 1-ring Vertex piston (50 mm)
• High-compression monobloc cylinder head
• Cylinder head and base gaskets

Important notes :

• Requires long-stroke crankshaft
• M7 × 120 mm cylinder studs recommended
• Minor engine case modifications may be required (clearance for connecting rod)
• Not street-legal in many regions
• Euro 4 models may require a temperature sensor adapter (M12×1.5 vs M14×1.5 on Euro 3)