S&S Cycle 106in. Big Bore Kit - Black Powder-Coat 910-0206The 106in. Big Bore kit yields excellent results with stock cylinder heads Feature the largest bore (3. 927in.) that can safely be used in a cylinder with stock spigot diameter Even though stock cylinders can be bored to fit the 3. 927in. pistons, the included S&S cylinders feature a much stronger liner to stand up to the added power Easy installation: no need to bore or split existing cases, just swap the cylinders Specifications: 3. 927in. bore, 4 3