Now that I have finished running out to the garage to make sure that I do not speak incorrectly, here goes.
First let me quote the Suzuki Service Manual...
On the last line of the first paragraph on page 2-12 it says: "Use the side stand for accurate adjustment".The SSM
does say to raise the rear wheel to check for
belt wear but for adjusting the belt the wheel is supposed to be down. So, if the "stealership" does it that way, then they do not even follow the manual. That's really inspiring and the reason I am a "handyman"
However, just like using the gage is about useless, so is that whole approach, IMHO. Here's why.
I know it seems right to raise the wheel, but as the rear wheel moves up the belt actually gets tighter. The reason is that the swingarm and pulleys do not follow the same upward arc. The pivot of their centerlines are offset.
(Note: that is why older dirt bikes had to run a loose chain with all their wheel travel)
Like the manual, I prefer to have it on the side stand because that puts some load on it. When you sit on it, it gets even tighter. Check it out. Adjust the belt to spec, leave the gage in there and have someone bounce slowly on the seat while you watch. You'll see the gage get tighter. Now just imagine going over a speed bump.
Everyone can do it however they choose. I just know that this topic comes up all the time, and I hear the same solutions over and over. Why? Most likely because the "stealership" adjusted it the "last" time.
(Note: the 90 degree method is an old industrial maintenance practice for checking belts)
We had 2 non-squeaking Savages (before my chain conversion), and we do not use the gage or any dressing on the belt.
IMO, if you use the gage and use a dressing, you have nothing more than an extra maintenance job.
in the spirit of that logic you need to be sitting on the bike when adjusting the algn,tens..SO happy medium is all we can hope for...ssm and clymers dont take into account wild temp swings(in refrence to belt)like we have where i am..these conditions affect carb tuning,handling,starting issues etc...example 24f at nite 60f at 2pm bike characteristics will fluctuate........the silocone based dressing spans the gaps of the happy medium...its not rocket science just a handy tool..