I was originally going to attempt to adjust the tension bolt from the back side as some do but I struggled to get my old Craftsman torque wrench on it. I didn't want to spend the $40 on the BMW adjusting tool to make the tension adjustment from the front but got some pointers and ideas here for making a tool- which I did. That was pretty easy and worked like a charm.
A couple of issues I had. When I removed the alternator cover I saw that the belt had been installed incorrectly. Instead of the belt sitting within the top pulley, one of the ribs on the belt was outside of the pulley. That means the belt was slightly crooked. Maybe that was the chirp? Otherwise the belt was in good condition. A little rubber dust in the area but nothing broken, no pieces of belt lying around. I had a replacement belt- same part number as the one that was on the bike - Continental 4 PK 611 ELAST but there was no way this was going on, it was way too small. A quick YT search and I see that there's 2 belts available and one of em is a little longer. Not entirely sure why the same part number belt would't go on, but when I watched a YT video and a guy literally slipped it over both pulleys by hand I knew something was up. And despite having the same part number it's hard to imagine that the original belt had stretched that much when comparing the two side by side.
Anyway I decided to re-use the old belt since it looked OK. Will order one of the longer ones when I sort out the part numbers.
The other issue I had was accessing the torque bolt with my wrench. It's pretty tight in there. Maybe compounded cause I used a hex head bolt as the drive point of my tool. I finally got it by coming up through the front tele lever arm.
Anyway, here's the tool. I took some advice that was posted here and tweaked it a bit. The hex head bolt is short enough to allow the coupling nut to snug down on the tensioning bolt without bottoming out on the bike. The spring was based on the BMW part. Not sure but I think this allows tension to keep the adjusting bolt from slipping backwards and having the cam come out of the track on the backside. Not sure it was necessary, but it only added 2.00 to the 6.00 total for the part.
One later video I watched though did show putting the belt on and that's when it occurred to me there must be a longer one available as his slipped right in place with virtually no effort. And since the belt is being tensioned by lifting the alternator, why wouldn't a longer belt make sense?!
02R1100S,05R1100S(BCR), 
(2)-S1000XR 
