Strange Mystery Goo in Oil Sight Glass

[Lieutenant Dan]

Can anyone help me figure out what this milky white substance is that started appearing in my sight glass? Here are pictures:







At first it was just a little, but now it seems to be growing. And the oil is still there and still a healthy brown...

[Dirty Duc]

Your bike is complaining because you aren't riding enough.

Isn't it a bit early for winter?  For a more detailed explanation, see the many threads on this board available through the search function.

[Ddan]

It's condensation in the oil, go for a good ride and it will disappear. It tends to happen during cooler weather but short rides in high humidity can do it too.  As DD said, it's common and there are many threads about it.

[Lieutenant Dan]

When you finish a ride, the engine cools down, the oil contracts a little and air is sucked into the crankcase.  The air contains moisture, as air does.  When you then run the bike, the miniscule little bit of water that came in with the air evaporates, and gets pushed up the crankcase breather tube.  The breather reservoir is a deliberate low point, so as the water condenses out in the tube (being colder than the motor) it collects here.  Then when you stop riding, more air (with a teeny little bit of water) gets sucked back into the motor, and the cycle continues.  Do it for long enough, and you get a decent amount of water in the crankcase reservoir.

Incidentally, if you do lots of short trips, the water stays in the crankcase and turns your oil milky, and you freak out and post in tech.

sorry... took some decent looking, but you're right.  yes... it is amateur hour in here...

[Ddan]

sorry... took some decent looking, but you're right.  yes... it is amateur hour in here...

SO the next time the question comes up, you get to be the first to reply, and the circle continues      

[Slide Panda]

Ahem...

http://www.ducatimonsterforum.org/index.php?topic=12023.0

[scduc]

While we all love our bikes, it's NOT ok to make love to them. 

[ducatiz]

SO the next time the question comes up, you get to be the first to reply, and the circle continues      

[BastrdHK]

I found, once you have the bike at normal operating temp, turn the bike off and unscrew the oil filler plug.  The condensation gets trapped in the top of the plug when hot.  Wipe it clean and repeat as necessary.

[ducatiz]

I found, once you have the bike at normal operating temp, turn the bike off and unscrew the oil filler plug.  The condensation gets trapped in the top of the plug when hot.  Wipe it clean and repeat as necessary.

you shouldnt even need that.  Once the motor is over 100C the water boils off and is sucked up by the crankcase vent into the intake.

[BastrdHK]

you shouldnt even need that.  Once the motor is over 100C the water boils off and is sucked up by the crankcase vent into the intake.

Not in my experience.  Only the plug wipe worked for me.  I went on 100+ mile rides, and the marshmallow goo was still there.

[Howie]

Not in my experience.  Only the plug wipe worked for me.  I went on 100+ mile rides, and the marshmallow goo was still there.

100C as in centigrade, water boiling point, not 100 miles.  In cold, particularly damp, even with the oil cooler covered my bike often will not see much over 60^oC.  The only time I worry about "goo on oil sight glass" is when I can't see the oil level.

[koko64]

Since I ran a little K&N filter off the breather box, the condensation in the sight glass has vanished. I reckon the steam vapor is being released rather than condensing and dripping back down the hose in cold weather.

[Howie]

Since I ran a little K&N filter off the breather box, the condensation in the sight glass has vanished. I reckon the steam vapor is being released rather than condensing and dripping back down the hose in cold weather.

I reckon you are correct. 

[ducatiz]

With the stock breather in place the boiled condensate would get sucked into the intake and burned with the fuel.  With the kn filter much will remain trapped in the filter and hose and drip back in.