Foamy oil

[Dean Chowenhill <dchowenhill@xxxxxxxxx>]

Hi,
I am an newby to the Oilhead digest.  After many years of Airheads and active in the Airheads organization and digest, I sold my last airhead (what was I thinking?) and bought a 1995 1100GS - Oilhead.  I ride a lot - 50 miles daily to work and have done n Iron Butt on the 1100.
I have many questions including about relocating the fuel filter, but right now I have a particular problem:
Today, I decided to change the oil.  Routinely, I drained it and put in fresh oil - GTX 20-50.  After filling it to the dot in the middle of the site gage, I started the bike (still on center stand) and ran it for one minute.  Re checking the site gage I was surprised to see it filling up (all the way to the top) with foamy oil.  Puzzled, I drained about two quarts to look at the oil - light brown and foamy.  
What is this all about?
dean
BMW1100GS, CA
Triumph Sprint, CA
Harley Soft-tail, CA
Yamaha Diversion, France

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