290cc ATHENA cylinder kit Ø83mm large bore, cylinder / piston for YAMAHA YZ F 250cc 2008 to 2013

Athena's Big Bore cylinder guarantees an increase in performance that can be observed throughout the power curve, keeping reliability on par with the original components.

The kit includes the high-quality aluminum cylinder with increased bore, the piston complete with piston pin and rings as well as all necessary gaskets.

All kit components have been developed to withstand the highest temperatures, pressures and stresses and have been validated by technicians with rigorous bench and road testing.

This kit can be installed without making any modifications to the engine crankcase.

Athena's cylinder kits and components are recognized worldwide for their performance, durability and reliability.