Smoke from the crankcase filter?

Good morning all.

I have a 1977 KZ650B1. It has pod filters, so I put a crankcase vent filter on the L-shaped hose that origially led from the crank to the airbox.

Yesterday I rode the bike to work and back. In the morning it was maybe 50 out, everything was fine. Parked the bike outside for the day. On the way home (temperature - near 80) I had a steady stream of white smoke flow from the crankcase vent filter the first five minutes or so of my ride home after the engine had warmed. The smoke stopped when I shut off the engine. I started it back up and rode home, after five or so minutes the smoke stopped completely. The oil level didn't drop, the bike ran fine.

Condensation in the filter from the cool morning burning off? Or is something else going on here? I haven't had this occur before. More than 1,000 miles on this bike since summer without smoke.

It ain't smoke, tis water vapor/steam... I would think about changing the oil at some point. Some condensation does get in there and I would think that this issue would be pronounced when there were wide temp ranges... 50? Where the heck do you live hehe... that is COLD! Anyway, you are seeing condensation burn off and if you run the bike in stop and go traffic or it has sit awhile and not been started and run regularly, you should likely change the oil more often. Probably don't need to change the filter every time but the "smoke" tells me that the oil is slightly fouled with water.

ad your location and bike to your signature line found in the member controle section of the site.

sounds like your up north like me :side: