180cc Big Bore Kit for GY6 based 125/150cc + engines. The bore is 63 mm, meaning the cases must be worked to accept the cylinder. This requires precision work, as the clearances are pushed somewhat. This is not a simple installation. The kit is compatible with all air-cooled 4-stroke 125-150cc Kymco engines (Maxi-scooters) and most Chinese import 125/150cc Scooters, Quads and Buggies with GY6 engines (not Kymco). This cylinder kit can be used with the original cylinder head. For those who want even more, there is a camshaft with modified timing. The highlight of this Naraku cylinder kit is the forged pistons, which offer better durability and reduced friction. The raised piston skirt also ensures higher compression. Supplied as shown. Select replacement parts from the list below as required.
Please note: If purchasing this kit for the Sym 125cc scooters, please ensure your engine is the GY6 version (cylinder head stud holes have a distance of 63mm hole to hole, outside to outside measurement).
Please note: If purchasing this kit for the Sym 125cc scooters, please ensure your engine is the GY6 version (cylinder head stud holes have a distance of 63mm hole to hole, outside to outside measurement).
