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Oil leak

greenmachine

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calgary alberta
Hello
Ive been fixing up a '73 K3 over the past year. I have it on the road now but there is a constant oil leak when I run the bike at higher speeds. In the city during calm ride it does not happen. The oil appears to be coming out of the overflow hose from the oil tank. I have lowered the oil levels considerable (still within range on the dip stick) but I still get oil coming out and covering my rear tire. When the bike is off and sitting in the garage there is no leak. Only when its running at a higher speed. I have looked all thru the bike and find no other wet spots or potential leak sites besides this hose. Has anybody had this issue before or does anyone know how to fix this?
Thanks!!
 
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Never had the problem, The only things I can think of is the oil pump check valve leaking and the crankcase has a large amount of oil in the sump, Once the engine is started it is combined with the tank oil giving it an overfull condition rising to the breather on the tank, Check the oil level parked with the engine running at around 3k or more RPM, Or the oil tank itself, I,m not positive but I believe there is a baffle inside the tank that could have came loose, Also check the valve cover breather hose for kinks or blockage. There might be someone that has had this problem that could help You more.
 
Sounds like valve cover breather is plugged somehow forcing oil out when it can't vent. But it could be any of the other stuff pointed out above too..
 
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