TWO WHEEL WERKZ Main Girdle for the Suzuki GSXR is constructed form heat treated 4130 chromoly for superior stregnth and rigidness. Our Main Girdle is designed to help prevent your cases and crankshaft form flexing in extreme horsepower applications. Combine with our bottom end stud kit for the ultimate bottom end upgrade. Designed for 9mm studs, may require drilling if your studs are .375" diameter.