My 2007 GS500F was sitting in storage since I bought it two months ago. Yesterday I had the time to address the mechanical problems that were keeping it from being ridden.

The following are some of the issues I found and how I dealt with them.

-  missing gas cap bolts. Replacements found in a local hardware store. Disassembled, cleaned and lubricated the gas cap
-  Tank petcock was installed backwards and missing the screen. I replaced it with a new one.
-  the choke cable was wrapped around the throttle cables putting extra tension on it. It operates much smoother now.
-  fuel hoses and inline filters were hanging close to the chain. Cut off the extra and cleaned up their placement. The filters were filled with crud. I was able to reuse them by cleaning them with carb cleaner (they are screen, counter person at the local dealership said they were stock?). Taking them out is on my to-do list but I'm still on the fence. Having them in makes it very easy to remove the gas tank (in my opinion).
-  jets were clogged, gunked and looked like they have corrosion on them. The bowls were filled with brown gunk. I took a shortcut here. I previously bought a used set of carburetors to poke around in and clean for parts. I just replaced the bowls and jets.
- left float was set to half the height it should be. I emptied this one last during disassembly and noticed it was holding a lot of extra fuel. Now I know why.
- mixture screws were set to 2.5 and 3.5 turns out. I set them both to 3 turns out
- synched the carburetors by ear. My right carb was popping and spitting when I blipped the throttle. When adjusting the synch screw a turn or more out the idle increased but blipping left me with a hanging idle. When I tightened the synch screw it appeared that the left carb was popping and spitting. The end result was tightening a full turn. With the air cleaner installed I no longer have a hanging idle.   

I searched the forum for the problems that I had and luckily found some things that worked for me. Please let me know if any of my observations seem off. As always, drive safely and good luck!

Inline filters are not stock! ... some people like them. .. I'm not one of those people... not going to start a sling match about inline filters tho.