A great older GS resource..

[seamax]

Found this on GSResources.com. It's a great site for owner's manuals, service manuals, wiring diagrams and how to's for older GS models.

Found a service manual for my GS425 here.

http://members.dslextreme.com/users/bikecliff/

[Big Rich]

Agreed. Basscliff is the MAN for putting that data together.

There is also a lot of good info there for cleaning carbs, valve checks, and other stuff. It was all put together for older GS's,  but it's still fairly relative to "newer" Suzuki's as well.