S&S Cycle 106in. Big Bore Cylinder Kit - Black Powder-Coated 106-3760 No need to bore or split the cases, just swap out the cylinders Matching silver or black wrinkle powder-coated finish to match stock finish Superior cylinder liner material over stock, drag and dyno tested 3.927in. bore, 4-3/8in. stroke, 10:1 CR on stock heads, 9.7:1 CR on S&S 89cc heads This project requires a skilled technician.