Ok, I was asked for some parts ID help.
I have not parted out very many KX500's in this year range so please correct me if I'm wrong.
86 kx500 uses it's own valves.
They are Steel if I'm not mistaken.
87-88 kx500 uses the same exact valves as each other and I believe they are made from aluminum.
If I'm correct, the 86 valves will interchange with the 87-88 valves.