Chinese ATV Cylinder Head Assembly 52.4mm - 125cc Complete cylinder head assembly with valves and cam for 125cc 4-stroke engines.  Fits many makes and models of 52.4mm engines.  Check pictures, specs and measurements for verification of the correct part. Head description: Intake port diameter: 23mm (0.90 in) Exhaust port diameter: 20mm (0.78 in) 28 tooth timing sprocket *NOTE: If your valves measure 23mm/28mm this head will not replace your head.  Your engine is a 125cc 54mm and requires a different head.  This head ONLY replaces heads with 20mm/23mm valves. Shipping details: Do you need your head fast?  If you order before 3:00 pm CST, Monday thru Friday, your order goes out the same day.   Buy now!