Factory assembled and trued to OEM specificationsDrop in replacement crankshaft requires no modification unless noted CNC machined and dynamically balanced to suit the increased strokeAdd +2.00 mm to +4.00 mm of stroke depending on applicationUses stock piston unless notedMain bearings not included Can be matched with Cylinder Works Big Bore cylinders to get significant displacement and horsepower gainsNot re-buildable as the rods are shorter than OEM.