Originally Posted by
Yogurt
The choice acids of this forum (Oxalic & Phosphoric) would definitely remove the rust, but you might get left with lots of pitting depending on how bad the rust is. I haven't used phosphoric acid, but I know it leaves a coating behind that actually prevents rust. I think it is the kinder/gentler of the two.
Actually phosphoric acid leaves behind a primer-type surface that needs to be painted otherwise it WILL rust.
I vote for Oxalic Acid since it won't harm the paint or most decals. Just be sure to rinse thoroughly, wax the outside, and use a framesaver product to coat the inside of the frame afterwords. I also soak my parts in a baking soda bath after the OA bath to ensure all acid is neutralized. Do a forum search for Oxalic Acid for more info.