valve rotating mechanism not only has ructions of common valve spring retainer, but also can rotate around its axial line while valve is opening or closing. It can let valve, valve seating, valve guide bush wear evenly. Through their lapping, carbon deposits can be removed. It can prevent air leakage or valve sticking . Valve is uniformly heated or cooled down, which can prevent valve disk from twisting and increase its use life more than 3 times.