Hey, hopefully this is in the right thread... but yea of the notches on the left rear swingarm, how tight should the chain be on an '05 GS500F? Bought it used so i dont have an owners manual.
using the string method ( http://www.yamahafz1oa.com/sportryderswheelalignmentmethod.shtml ) instead of the marks, you should have 7/8" - 1 1/8" of slack at any given point. Do it in neutral and you can roll the bike forward/rearward to ensure there are no tight links.
this method makes sure BOTH wheels are inline, and can be done in less than 10 minutes including gathering/replacing tools. i did it saturday in 7 ;)
good luck !
thanks very much!