Z155 Cylinder Head Kit. Complete cylinder head with all parts assembled. Not the same as a YX160 Cylinder Head but will fit. I ntake Port Angle Is Different. Valve clearances will need to be adjusted and set before installation. Must be installed by a professional. If damage is to occur this will be due to incorrect installation. All Castings have little holes in them around the head, these are drain holes for water. Photos of head will be sent to you before dispatch as proof the item was undamaged, we have had customers in the past assemble the part. Caused damaged and try to return as unused. There are 2 types of exhaust port angles, this would make your exhaust down pipe come out at a different angle. CRF PORT ANGLE – Has 6mm exhaust studs and has casting stamp on cylinder head fin above spark plug = “02”. KLX PORT ANGLE =CRF PORT ANGLE – Has 8mm exhaust studs and has casting stamp on cylinder head fin above spark plug = “01”. Cylinder head – CRF PORT ANGLE. Inlet and exhaust valves fitted. Camshaft and tappet covers. Rocker Arms, Pins & Adjusters. Camshaft Sprocket (34T) & Bolts. Parker Racing Pit Bike Supplies is a new company on the market but has over 8 years experience in “pit bike supermoto” racing, including multiple race and championship wins. Please feel free to ask any questions.