http://www.buykawasaki.com/Default.asp? ... intParts=0 has parts diagrams for most bikes. Just follow the steps and you will get to the parts diagram for the KDX. Goto the carby section and it will tell you the stock jets and the optional ones.
Here ya go.
STOCK NEEDLE is R1172N
MAIN JET IS 150
PILOT JET IS 48
"I want to die peacefully in my sleep like my grandfather, not screaming in terror like the passengers in his car."