I realize this is a hopeless stab, and that i'm avoiding reality, BUT:
Sunday I attempted to get my new (to me) 2000 WR400 to run. The float valve was leaking, so I rebuilt the carb. Once I put the carb back on, I also installed a PMB Insert in my uncorked exhaust. I could not get the bike to start. I realize that this is because I changed too many things when i rebuilt the carb (float height, idle speed, idle mixture, exhaust insert).
Well, finally by bump starting the bike on Sunday, I got it to run. I was attempting to tweak the idle mixture (in order to keep it running I had to have the idle very high), and the bike *presumably* overheated and coolant spilled onto the ground. At that point I shut it off immediately and called it a day.
Flash forward to today, Wednesday. Based on Sunday's results I do some further tweaking. I get the bike to catch on the second kick and it is idling almost like new! My relief was short lived, however because I decided now that i had it running, it was a good time to check the oil level. Well, that is when i found that the oil was VERY runny and ready much too high (bad sign).
So, I dropped the oil and it looked as you see pictured. DANG IT.
So, my question is: Is there a chance that it is NORMAL that when the bike overheats some coolant gets in the oil? I realize this is 99% unlikely, but as a street bike guy I continue to be surprised by how tolerant of abuse dirtbikes are.
TLDR; overheated the bike, ran it a few days later for 60 seconds, checked oil level and found coolant.
I suspect I will be told I have something internal going on (blown head gasket?). But heres hoping...