Cylinder Works High Comp Cylinder Kit Arctic Cat / Kawasaki / Suzuki 400 Cylinder Works High Compression Kits serve as high-performance cylinder upgrades, upping compression and addressing cylinder wear issues. Complete with brand-new OEM replica piston(s) featuring the same bore but with changes to raise compression. For a quick overhaul you will find cylinder(s), rings, gaskets, and all necessary hardware in the box. Vertex heat treated, T-5 hardened piston(s) are included in the kit. Depending on factory spec they will either be tempered cast or forged and feature molybdenum disulphite skirts. Coupled with the diamond honed cylinder sleeves, to ensure precise bore dimensions and optimal surface finish, this combination provides effective ring seal and oil retention. Specifications: Includes Vertex #23550 Compression Ratio 13.5:1 Cylinder Diameter 90 mm Cylinder Kit Type: Standard Bore High Compression Displacement 400 cc Features: High compression kit includes piston(s), cylinder(s), rings, gaskets and hardware required for assembly Higher compression than stock while maintaining factory piston diameter Replacement cylinder designed in-house by Cylinder Works Diamond honed and nickel silicon carbide (Nsc) plated cylinder wall plating for longer life OEM replica piston design in cast or forged design (to match factory hardware) Gravity cast aluminum alloy pistons feature 18 silicone content for extreme lightness Forged pistons are forged from 2618 aluminum for superior strength and durability Piston supplied and manufactured by Vertex (Italy) Piston skirts treated to molybdenum disulphite coating for increased piston life, quicker break-in and reduced running noise Nickel silicon carbide (Nsc) cylinder wall plating for longer life New, not remanufactured, cylinders and pistons Gasket hardware supplied by Vertex and manufactured in USA Piston profile optimized by Vertex to match compression ratio, cylinder design and ring spec for each application Note : Image for reference only. Kit contents vary with application.