In article ,
zxcvbob wrote:

...on a bicycle that hasn't been used in a while. It doesn't look
rusty, but that's probably what it is.

Liquid Wrench, or WD-40?

Bob

We have a militant contingent of WD-40 detractors in a.h.r., but the can
says it "loosens rusted parts" and "frees sticky mechanisms," and it
does, for me, every time.