Topic: Smoke from top end (help me style thread)

[Tretnine]

So, there is smoke coming out of my breather tube. What would cause it? Here's my situation.

I've been having a hailstorm of a time getting my carbs set up correctly on my 78 cb550k, particularly the idle. (Rebuilds and sticky floats.) So, currently, it idles poorly, but I did go through and do cam, tappets, timing, etc for my spring tune up. Since then I've also put on a new carburetor but it's not the 69a. I can't think of the number stamped on there. Anyway, after driving a while smoke will come out of my breather tube... badly set valve clearances? Burning oil? Something completely different? (10k motor so low-ish miles.) TIA

[333]

Some of this is normal,but...

Is it smoke, or could it be steam?  Water sometimes condensates in the crankcase and will vent as steam when the motor is hot.

My other thought is; what is your compression?  If you have a bad exhaust valve seal, the escaping hot gases may be burning off the oil.