I think Rob-grout hit it. I get condensation from short runs. Running the bike for an hour at higher temps clears it up on mine. It ain't just a KLR thing. Everything I ride gets it when the temps get below freezing. The engine develops condensation. If we don't run them long enough, hot enough to burn the condensation off, we get a milky residue on things.
Engine oil has emulsifiers in it that is intended to trap moisture and that is what you are seeing. It shows up at the coolest part of the engine, like the oil filler cap. You should go to Minnesota and pull an oil cap off a car during the winter that never leaves the city limits. Looks like a milk shake.
If you change the oil you should reduce the problem temporarily. But moisture depositing will return unless you get the oil hot enough to really vaporize any water that may condense into the oil. The brand of oil will not change this reality.
I tend to allow all internal combustion engines to warm up before blast off, more so when it is cold out. I want to believe I find less condensation in the sight glass when I do this. YMMV.
“many a trip continues long after movement in time and space have ceased”- Steinbeck, [I]"Travels with Charlie"
[FONT="Century Gothic"][I]Sometimes your only available transportation is a leap of faith[/I] [/FONT]