I have a very loud squeak similar on my 97 but bike is coming from my ac compressor in the clutch that engages it

 

I finally fixed this problem on mine today, it was another poster in this forum that suggested pulling the power steering pump pulley out by 1/8 of an inch. I honestly couldn't think of why this would work because the noise seemed to be coming from the top idler pulley but it worked. No more noise!

I wish I had tried this before I replaced all three pulleys, the belt (twice) and rebuilt the alternator with new bearings.