I have a small amount of black corrosion on the lugs of a Schwinn I recently purchased. I tried WD40 and a stiff toothbrush, but this didn't seem to do the job. Any suggests on how I can clean this up without damaging the paint?
oxalic acid...do a search of this in the archives and read all about it.
Thanks looks like a trip to Home Depot is in my future.
Note that OA will bleach out the dark spots to white. You will need to apply touch-up paint to cover.