ATHENA Cylinder Kit - Ø40mm for Derbi, Aprilia, Gilera

This POWER VALVE SYSTEM 2-stroke engine top end regulates the exhaust opening time for excellent performance at low revs and optimised performance higher in the rev range.

• ATHENA Power Valve System: "guillotine valve" installed with a pneumatic system
• Operates using exhaust gas pressure
• Optimises performance and retains maximum reliability
• Supplied with 241012 piston and 601494 gaskets