IMO, belt noise on the LS is related to the ball bearing in the rear pulley hub. That bearing is a single groove ball bearing and is usually in the toilet at about the 1000 mile mark. Once that bearing is loose, no amount of fiddling with wheel alignment can stop the noise. That's because it's not the wheel that's out-of-alignment, it's the pulley. Installing a double row ball bearing fixes the problem permanently. I've logged about 82,000 miles on my Bejing Bearing and the belt is still quiet as a church mouse. The bearing is still smooth and shows no signs of wear. Almost no pulley side-to-side play.
This old post provides the gory details. It's easy & cheap (at least it was cheap 5 or 6 years ago). Check your rear pulley for excessive play.
http://suzukisavage.com/cgi-bin/YaBB.pl?num=1561964431