I have a trek 470 which may have extremely few miles on it, even though rims are worn from defective brake pads. The components are all RSX.
There is a metalic whistling sound when turning the cranks even with no load (front or back). It appears to be comming from the cassette/RD area. It started today, and seemed to go away when down and upshifting. It doesn't seem to go away anymore. I've tried Heavy lubing. The RD seems lined up with the cog.
if the bike doesn't hesitate when shifting, then the tension is correct for the RD.
I'm not sure what a metalic whistling sounds like (anyone listen to Car Talk where they make people imitate the sound their car makes? ) but it could be that the rollers for the pulleys in the RD are dry and need lube. have you tried lubing them and also the pivot points of the RD?
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