I have a 2006 Kawasaki bayou 250. I went to change my oil and when I took the oil cap off I noticed a milky substance in the cap and in the engine. Could anyone tell me what this means.

 

You can get water or moisture in the engine from several different ways. Since it's air cooled,you can get water from the air box if you do a lot of driving in water,vent lines from the carb or tank plus on some you can get a little amount of water just from moisture in the air that the carb sucks in that can accumulate over time in the engine.That hopefully is all that it is.

 

Not getting the engine hot causes the "Mayonnaise" effect. If you only do short runs or trickle about at low revs in a high gear, the engine doesn't get hot enough to vaporise condensation. Some engines are more prone to it than others, Honda 300s nearly always have mayo on the starter gears when you remove them to change a starter.

 

Yes that's another way merryman. I like your "mayonnaise effect" description on this..