At work right now and need to find out what the right size gas lines for the gs are.  I belive they are 1/4 but i need a confirmation.

For more than you ever wanted to know, check THIS OLD THREAD and related stuff.

The newer GS's use 10mm lines (actually the carb and tank ends are 8mm, the frame mounted petcock is 10mm)

You can get a straight 10mm line to hose, just clamp them down hard!