KZ 440 - too much oil from the engine breather

Hi guys,

I am very new here. First of all, sorry for my english.

Few months ago I bought Kawasaki KZ440 1980 (type C1 according the pictures in the manual). The bike was not starting, oil film everywhere. That time I thought the case would be gaskets/sealing on the motor. I made basic maintenance, new starter, carb cleaning, etc. The bike runs well. It is the German version – 20kW only.

There is going too much oil from the breather on the top of the cylinder head cover. The bike is in original status and nothing is missing, I think. There is a hose from the breather going to the airbox, then the oil goes through another hose down to the ground. I tried to catch it and after 100km it is like 100ml (0,1l). Looks little bit too much for me. I have to say, that due to the 20kW, I am riding almost all the time it the second half of the rpms. This is how it looks.

www.partzilla.com/catalog/kawasaki/motor...b1/air-cleaner-80-b1 (it´s written B1, but this IS how it looks like in my case.)

I checked the topics here and it should be caused by the „relief“ valve behind the clutch. I dismount it and clean it. No damage, the ball and the spring goes smooth, but needs surprisingly big power to move it. I cannot imagine, that oil pressure can move it. Should this be the case anyway? The oil is spitting same.

Oil amount is in the middle of the window. So too much oil is not the cause.

The bike is great, I love it, but …. Can anyone help me, please?
THANKS!