No problem, I just got a WR 450 Yamaha that has sat most of its life, I had to spend hours cleaning and polishing the gunk off to get it to run again. Here is what I've learned
1) as stated throw away the old jets and buy new, they are cheap!
2) soak varnashed parts in carb dip overnight (never put rubber or whole carbs into dip!).
3) simple green cleaner takes off the white stuff that grows on steel bits in float bowl (spray and rinse with water, don't let it dry or it will form concrete).
4) rinse parts with aerosol carb cleaner (again stay away from rubber).
5) use shop cloth and carb spray to clean jet needle interior passage(you will be amazed how much stuff polishes off that soaking misses).
6) when you think its perfect, clean it again!
7) quadruple check the passage from the pilot jet through the carb body (use aerosol and compressed air to make sure its 100% clean)
8) check fuel petcock, inside tank and fuel line along with passage from line to float needle for varnish or yellow
slime, acetone will disolve this crap.
9)
USE FUEL STABILIZER! and drain float bowl if its going to set more that a couple weeks!!!! Much more fun to ride than work.
I worked for years at a KTM dealer and spent months every spring fixing this on bikes that sat all winter..
Thanks again! Hope this helps a few poor souls that are missing prime riding season with gunked up carbs.