I was working on my 1999 GS500 this weekend - and I noticed a strange thing with the little fuel value on the left side - it is labled res/pri/fuel at 9/12/3 o'clock respectively. However, the knob only rotates to 6/9/12 o'clock.

Did the previous owner do something and then put it back on incorrectly? I've been looking around for a picture to compare it to but haven't found one yet so I thought I'd just post here! Thanks. At this point I'm assuming it's wrong ...

Nothing wrong with your valve. I guess they put the word "Fuel" so that people would know what the thing does.
I only rotates between 6,9 and 12. I beleive 6 has "ON" label, doesn't it? 6 is "ON", 9 is "RES" and 12 is "PRI"

Jenya