Oil leaking from somewhere please help.

Hi Folks.

I have a kz1100 shaft drive 1981 A2 Model. I have just overhauled my topend, new rings, vlave stem seals gaskets etc.
The problem I have is this, everytime I go between 5000rpm and 6000rpm oil is being sprayed on my right hand side pants. Nothing from the left hand side.
Could this be to the head not being tightened down correctly or something. When bike is standing there are no oil leaks what so ever, even on the engine right hand side none that I can see. Is there anyway to check for spraying oil from head gasket. Any help will do. Thanks
PS When below 5000rpm nothing.

I ruined a couple pair of pants the same way. On mine, I found oil was leaking from the valve cover gasket where the rubber half moons are. Used a small bit of RTV and no more leaks. Not sure if this is where your issue is but thought I'd pass along my case.

Thanks Deacon...will look into that.

When my Z1 leaked it was from the valve cover as well and where the tac cable entered the engine. Put in a new gasket with APE half moon cam covers and permatex and a new O ring at the tac cable. Still have a tad of seepage but not too bad but like you it's hard to tell exactly where it's coming from.

If you are not sure where your leak is maybe you could wash and dry the engine and run your bike untill it leaks. Oil like other "stuff" runs down hill. Start looking from the top on down and where you see the wet spots start is probably the area you need to address.

On a side note where I work we do a dye penetrent test to check for cracks in parts. It's a three step process. First the part is cleaned of all oil. Second a red oil is sprayed on and allowed to sit for a bit while it seeps into any cracks. Then all the oil is cleaned off the surface with the cleaner and a developer is sprayed on the part. The developer is like a white powder chalk and draws the red oil out of the cracks. I've thought about using just the cleaner and the developer on the engine to see exactly where the oil is coming from on my bike but for now I'll wait till winter.

It is most likely coming out of the valve cover. Have you pulled off the tank and looked. By the time it reached your pants it might be pretty messy up top...Russ