KZ Mystery. Guru Needed

I bought my 77 KZ750 in April. It had 10,00- miles on it.

Runs like a dream. BUT Ive noticed something. It burns oil. Not visibly though. Smoke NEVER EVER comes out of the exhaust.

I ride it hard but never to redline. Last month I changed the oil and put in 10W40. After 200-300 miles of hard riding, I added more oil but made a mistake: I have a few bikes and thought the 77 Kawa took the same oil as my 77 XS650. So i put half a bottle of 20W50 in it. Didnt change it, ran it.

Checked the oil today after another 200 miles of hard riding, and the float level is at half.

Has anyone experienced this? Ive heard it said that a dirty air filter can cause this? Im open to suggestions and diagnosis.

Valve guide seals can do that. I put in Rotilla 15-40 and it stopped burning oil. If the seals are really bad, it won't help.
Steve

SWest wrote: Valve guide seals can do that. I put in Rotilla 15-40 and it stopped burning oil. If the seals are really bad, it won't help.
Steve

Is there any other way to tell of the valve seals are bad? And would they be bad at 10K miles?

and do you mean this oil: www.autozone.com/motor-oil-and-transmiss...-2-5-gal-/319570_0_0

Pic of the plugs? I get a gallon there for about $17.
Steve

SWest wrote: Pic of the plugs? I get a gallon there for about $17.
Steve

Im going to be away until Friday so cant get to the bike to plug the plugs until then. I guess
i might see oil on them if its a valve problem? Like I said, i have NEVER seen the bike smoke at all.....hmmm

Just rebuilt?
Steve

The valve stem seals do the hardest job of all engine seals.
The heat and the age of decades made them hard as stone and so they lost their sealing properties.
There is only a small lip on the seal that hold the oil away from leaking (sucking) down the stem into the
combustion camber and then burned away,.
I my self changed valve stem seals more than 100 times for me and my friends cars and bikes without removing the head .
and after the seal job the oil consumption goes nearly to zero between the oil changes!!!



Tools for valve seal change

SWest wrote: Just rebuilt?
Steve

nope

In my opinion, having several brands of UJMs, Kawasaki made the best bikes of the 70s. HOWEVER, one thing I DO NOT like is - their bikes dont have a dipstick, which leads to confusion.

My bike was not on a COMPLETELY level surface, which lead the level to read a bit low. After letting the bike sit overnight, it appears the level is as it was when I last added oil. So there is no burning oil issue....thankfully!