Recently back from "sibirsky extreme project" the conitions on the BAM were very extreme, 100s of deep water crossings, and very deep ones where the xt was buried up to under the seat in massive "puddles " and it just sat there ticking over.The only time it stopped was when the water came over the seat and got sucked in through the snorkle, then it had to run on milky oil for 2 days ,then cheap diesel oil for 1000mls and mineral car oil for another 2000mls before i could find some proper bike oil.After all that a thrash home from moscow at 80/90mph+. and it still runs perfectly.(apart from the annoying fuelling ).
The xt is one hell of a tough bike. 10,000mls in 9 real hard wks of thick dust and water.