Topic: Oil Vapor Normal?

[03rangerxlt]

Bike: 1972 Honda CB500 - No engine mods - semi-synthetic Hondalube oil (forgot the weight, whatever my old Honda service manual recomends)

I took the bike out for a quick run to see how the clutch felt do to an engagement issue (I was sitting at a red light and it started feeling like my clutch was starting to engage without my permission). 

So I got the bike home and into my garage, I let her run while I took my gear off, and I notice a faint blue smoke coming from under the motor.  Naturally concerned, I investigated that, and found it to be coming from the breather tube from the top of the motor.

Damn, I'm such a newb to this...
...sometimes I'm sure I'm asking stupid questions.

So, is it normal to see some faint blue smoke come from the breather tube, or is it a sign of something bad.

The last time I saw something like this, it was coming from the breather thing on the valve cover of my 2.3 liter Ford Tempo.  It was my understanding that the oil vapor I was seeing was caused by bad rings. But I was seeing so much of it that the oil was condensating on the bottom of the hood over the motor and dripping everywhere.  It was so bad that my friends called the car the "smoking dragon," because at night, the headlights illuminated the blue smoke coming from under the hood and it looked like a dragon's nostrils breathing smoke!

A couple of weekends ago, I changed some of the oil pump gaskets.  I followed the directions in the Honda service manual from teh 70's and drained the oil out of the pan like a dumba$$.  Hey, like I said, I am a total newb as this stuff.  Learning as I go I guess.  Anyways, I was running Castrol bike oil before this and I replaced it with semi-synthetic Hondalube.

Is the faint blue smoke from the breather tube anything to be concerned about???

I hope this isn't another thing going wrong with this bike! lol

[flybox1]

look down between your rear case, and your inner fender, tucked under and behind your electrics.  there might be a unit that the breather tube fell off of.  it recycles the vapor through a sponge-like filter (to separate out the moisture) and routes it back into your airbox.  the moisture falls through and into a plugged hose, to be emptied and cleaned with service.
if you have this unit, get it cleaned out and the hose re-connected.
if you dont, plug this vapor hose with a small filter

[Lostboy Steve]

Mine did that during break-in (after an engine rebuild) Now not so much, I also had an open breather, but have since routed it back into the airbox, but without the sponge filter.

[03rangerxlt]

So some blue vapor is okay then.  I just have the tbe tucked down by the swingarm, just below the the frame.

[MCRider]

So some blue vapor is okay then.  I just have the tbe tucked down by the swingarm, just below the the frame.

It's not normal, if this were 1972. In 1972, a 1972 CB500 wouldn't smoke. 40+ years later, you've got old and tired piston rings, valve stem seals, same as your Ford, just a matter of degree.  If you can live with it, fine. If its too bad, you're looking at a top end overhaul. Not the end of the world.  It's only as bad as your ability to tolerate it.