On Saturday, I cleaned the bike with the power washer - top down.

Today - Monday, I turned it upside down to remove the wheels and begin 
cleaning them - and the first step is using isopropryl alcohol to get 
rid of the grunge - as they were really nasty. 
 
Then I got to looking at the underside of the Bike - *WHOA* it was 
bad. You would never guess that I had power washed it.... and all the 
fine particles.... causing wear and scratches - well, they came from 
the bike trail. The South side bike trails have all been black-topped, 
while the North side are shill powdered chips. I remember, after it 
was done - seeing so many fine white chips/powder affixed to my bike. 
Those fine white limestone chips are just an abrasive! 
 
So I threw the bike in the bathtub - made up some car soap - and 
cleaned the underside! 
 
I don't have pictures of it when dirty - but it was nasty and severe.....