Cylinder Bore:63mm/2.48″ Exhaust Port Diameter:30mm/1.18″;Bolt Hole Spacing:50mm/1.96″.Intake Port Diameter:26mm/1.02″;Intake Port Bolt Hole Spacing:45mm/1.77″ Cylinder kit for GY6 4-Stroke GY6 150cc 180cc 200cc 250cc Engines ATV Off-Road Vehicle Scooter Go Kart Package including:cylinder body,gasket,94 chain,Rocker(as picture show) Warranty:We are always available to help our customers.Please message us for replacement or refund if you are not satisfied with the order pls confirm The size of the product meets your requirements before you purchase Note:please allow 0.5-1 inch difference due to manual measurement.1inch=2.54cm Size: Cylinder Bore:63mm/2.48″ Exhaust Port Diameter:30mm/1.18″ Exhaust Port Bolt Hole Spacing:50mm/1.96″ Intake Port Diameter:26mm/1.02″ Intake Port Bolt Hole Spacing:45mm/1.77″ Replacement for: For 4-Stroke GY6 150cc 180cc 200cc 250cc Engines ATV Off-Road Vehicle Scooter Go Kart Package Included: Cylinder body x 1pc Gasket x 2pcs 94 chain x 1pc Rocker x 1pc Keychain x 1pc About After-sales service: First of all,we sincerely apologize to you for returning exchange or refund caused by any reason.Please be assured,no matter what the problem.Please contact us first,we will do our best to solve any problem for you.We attach great importance to every customer.Your satisfaction will be our greatest impetus About GOOFIT: was established in 2000.We are a leading website selling,ATVs parts,Go Karts parts,Dirt Bikes parts pocket bike parts,Moped scooter parts online Company Culture: We are committed to providing the best products and services for our customers