Athena P400250100030 300cc Big Bore Cylinder Kit (85mm Bore) - Forged Piston Performance Upgrade, Converts 250cc to 300cc, Compatible with Kawasaki KX250 & KX250X 2023-2024 101 Bikes Keep your engine breathing clean

Keep your engine breathing clean and running strong

Our family of engineers

Its adjustable dual-layer construction ensures a snug

and provides unmatched engine protection against dust

a premium domed-head piston with a 10mm wrist pin

Athena P400250100030 300cc Big Bore Cylinder Kit (85mm Bore) - Forged Piston Performance Upgrade, Converts 250cc to 300cc, Compatible with Kawasaki KX250 & KX250X 2023-2024 101 Bikes Keep your engine breathing cleanUPGRADE YOUR DIRT BIKE TO THE NEXT LEVEL OF PERFORMANCE Extract massive power, aggressive low end torque, and unmatched acceleration from your 250cc four stroke engine with the Athena Big Bore Cylinder Kit (Part No. P400250100030), a premium race proven package engineered in Italy to seamlessly convert your factory setup into a high revving, high output 300cc powerhouse. Entirely cast from high grade aluminum and treated with a specialized Motor