So I have my 600mile old ST3, and it is five years old so I am going to replace the belts. The belts came in from LT, and I decided to check the tension as it sits now for a reference point. I thought an easy way to start would be to try the 5mm key method just to see what it feels like. Well I have watched the videos, read all the threads in a variety of forums, and there is no way I can get any hex key under that fixed pulley between it and the belt. On either cylinder. So I must conclude that the belts are extremely tight. Now I have used some software and a usb mic on my laptop to try and get the harmonic twang to get a steady reading, but the numbers fluctuate wildly and it is hard to tell what it really says. Suggestions appreciated.