I have a 12 speed Fuji Espree (not sure what year) that has Suntour AR components on it. Since the rear derailleur was looking gooped up, I decided to replace it with a Shimano 105 long cage 9-speed derailleur. Sheldon's website says this should work because derailleurs are not dependend on the number of gears you have. At the same time, I cleaned up the chain by throwing it in some degreaser. The rear derailleur went on just fine and after a struggle putting the chain back together, I greased everything up. Now the bike shifts much easier, but it is much noisier than it was before. I adjusted it by making sure the derailleur was lined up with the smallest gear when the friction shifter was in the up position. It appears to be aligned correctly, but it's noisy when I pedal.

Is there some other adjustment I am missing? Even when it is in gear, and everything appears to be lined up, it does not sound smooth at all. It doesn't make a difference how much I move the friction shifter to adjust the position of the rear derailleur.

I did search around and was unable to find anything that quite covered this issue. It's possible I was using bad search terms, though.

Thanks in advance.