Discolored in what way? A few years ago mine looked very grungy and gray, turns out they had loads of dust that had accumulated on them and didn't wipe off easily. I took a very damp cloth rag and wiped them down several times, rinsing it out in between, and they cleaned up quickly and nicely. Or do you have a different type of discoloration?

I used a soft brush and lots of water and soap on mine, then I let them dry under sun light.

The original paint is very scratch resistant.

Now they look like new 😁

I use a product which is like a shoe polish but especially for iron stoves. Works great and makes them nice and black again.

Thanks for your advices.

Due to the damages of the paint and its discoloration, I will directly use the satin black bumper paint that some advised in an older thread found on beoworld.

I will post pictures before/after if I can do it with my ipad.

Could you please give me a link on ebay or amazon if it is possible ? Thanks