This engine cylinder barrel piston gasket kit is designed for use in specified 250cc motorcycle models, including YBR250 (2007–2011), XT250 (2008–2022), XTZ250 Lander (2009–2018), YS250 (2014–2017), and ATV 250 models (2008–2013).It is intended for situations such as low compression, cylinder failure, or piston seizure. The kit includes: 1 cylinder, 1 standard piston, 1 piston ring set, 1 wristpin, 2 circlips, 1 cylinder base gasket, 1 cylinder head gasket, and 1 chain tensioner gasket.The piston features anodized treatment for improved heat resistance.Gaskets are constructed from materials to support effective sealing during engine reassembly. Kit specifications: - Condition: Aftermarket - Quantity: 1 set - Material: Aluminum - Displacement: 249cc - Bore type: Standard - Bore size: 74mm - Stroke: 58mm - Piston pin diameter: 17mm - Cylinder casting number: 1S400 Replacement part numbers: - Cylinder: 1S4-11311-01-A0, 4D3-11311-01-00 - Cylinder base gasket: 4D3-11351-00-00 - Cylinder head gasket: 5XT-11181-00-00 - Piston (Std): 1S4-11631-20-A0 - Piston pin: 4XV-11633-00-00 - Piston ring set (Std): 4XV-11603-00-00 - Piston circlips: 90468-12069 - Chain tensioner gasket: 5XT-12213-00-00 Note: Compatibility information is provided for reference.Please verify fitment by comparing with your existing components and product images before installation.