I did the leak down test today and the rings are at 40%.
I have always been meticulous about my air filter and check the air boot between the filter and the carb everytime I clean it to make sure no dirt/dust has gotten through. I even run a filter skin 80% of the time. I'm pretty confident it was not dirt that did the rings in.
Looking on line for piston & ring kits I cannot find anything for a 2010 KTM 530 XC-W. The only hits I get are for 530 EXCR. I'm assuming they are the same engine/piston, but want to double check.
The Wossner pistons come in 3 sizes (94.96mm, 94.97mm & 94.98mm) depending on cylinder wear so I'll have to wait till I tear it down to order.
So Many Idiots, So Few Comets!!!!!!!!!