While smoke/oil out of exhaust

I have a 1976 KZ900 that I had a oil leak on it around Christmas and found that the oil was leaking from the #3 header. I took the pipes off to check the gaskets and they were all good. I put the exhaust back on and the leak is gone. I started the bike up today and noticed that there is white smoke and oil coming out of the exhaust. No oil leaking anywhere. What could cause the oil to be coming out of the exhaust ?

Worn out valve guide seals or bad rings. If the compression is good, it's likely valve seals.

at warm up or all the time

I only had it running for about 5 minutes today and it was smoking/blowing oil the whole time.

For some reason I am thinking that I was doing the running sync on the carbs when I first noticed the oil leak. Is it possible that tightening down the screw under the carb tops to sync the carbs too much could have caused the problem that I am having with the oil coming out of the exhaust ?

that is a sign of fresh oil getting past the rings ...like said a compression test...have you changed the oil and filter

loose valve guide seal will smoke a bunch at first fire then clear some...maybe again when you punch it doing 35 etc...smoke all the time is rings in theory....did it do this before some or start all at once after the sync job...kooky if it started all at once

I started when I was doing the running sync. I changed the oil/filter last year sometime. I will have to do a compression test. It all seems to have started when I was doing the running sync.

How is your Oil level? Is it correct? Has the Oil been contaminated with Gas? Might be worth a oil change.

The oil level is high. I will be changing the oil and oil filter today, if I can get a filter from the local motor cycle dealer.

I changed the oil and filter today and put in 4 quarts of oil. I started the and it sounded good and did not see any oil coming out of the pipe. I wen to put fuel in it and got almost the gas station when the bike lost some power. Filled the bike up and limped back home. Checked for spark an dhad spark on all 4 plugs. Checked the pipes and the #3 pipe was slightly warm, not hot like the other pipes. Took the bolt out of the #3 carb bowl and the main jet fell out. Took the carbs off and the #3 main jet will not tighten up in the carb. I appears that whatever the main jet screws into is stripped. Can I retap the threads to fix this or how can I fix this ?

BIGKEVIN wrote: ...Took the bolt out of the #3 carb bowl and the main jet fell out. Took the carbs off and the #3 main jet will not tighten up in the carb. I appears that whatever the main jet screws into is stripped. Can I retap the threads to fix this or how can I fix this ?

Are these smoothbore carbs?

Perhaps this issue >> www.wgcarbs.com/index.php/vm29-jet-block-repair

Good Fortune!