Big Bore cylinder and piston kit- The only complete bolt on big bore 750cc. Big Bore Cylinder and Piston Kit.The Only complete bolt-on Big Bore 750cc Cylinder and piston kit ever made for the XS650 Yamaha. Modified limited production European Race Engine Cylinder Block has enlarged fins for improved cooling. The New Cylinder Block has longer fins matching the Head Fin Length. Kit Fits: 1974-84 447 Type Engines. Note : Stock Cylinder Bore size is usually about 75mm. Stock Piston size is around 74.945mm, and the standard size piston has. 945 marked on its top (the "74" is always dropped). Standard original piston size varies slightly so the piston may also be marked.
Standard bore clearance is 0.0020-0.0022 in. XS Performance Big Bore Race Cylinder Block with sleeves installed and finished to fit our 80mm. Cylinder casting has larger cooling fins that extend out the same distance as the cylinder head fins for enhanced cooling. No modifications to engine cases needed. 750cc Big Bore Piston kits(2) complete with Ring Sets, Piston Pins & Clips.
Forged 447 type Pistons feature. Valve pockets cut for large valves. Oil channel for enhanced piston pin oiling. Piston pins that are internally tapered to ends for weight reduction.
Lightweight 9:1 compression pistons. Big Bore Cylinder Head Gasket & Base Gasket. Fitted with our XS Performance Camshaft, Dellorto Carbs, a free-flowing Exhaust and Iridium spark plugs will result in about 65 Rear wheel Horsepower or more and 50 foot-pounds of Torque.See Dyno Chart 1 Dyno. This item is in the category "eBay Motors\Parts & Accessories\Motorcycle & Scooter Parts & Accessories\Engines & Engine Parts\Engine Rebuild Kits & Components". The seller is "xs650inc" and is located in this country: US. This item can be shipped to United States, Canada.