The Sparks Racing High Compression 480cc Big Bore Cylinder Kit is the perfect add-on for anyone looking to maximize the performance of their YFZ engine. Our custom cylinder is specifically designed for a 98mm bore, so there won't be any head gasket or cooling issues. Our one-piece cast aluminum cylinder with Nikasil plating is far superior to a bored or sleeved stock cylinder. This kit uses a brand new cylinder, so there's no need to return your cylinder to us. This is a high compression big bore kit which requires the use of race fuel with an octane rating of 110 or better.
