I've got horrible rust stains on my car's rims, and I'm at a loss as to how to get rid of them. A bit of googling suggests the use of steel wool, but I'm not sure how much I trust that. Any suggestions?
I'd try some CLR in a very small spot to see if it can remove it. I'm not sure the effect it will have on metal so try it in a very small/inconspicuous spot first (maybe on the very edge of one of the spokes).
The photo you have added is not of chrome rims. Chrome rims are a lot harder and can be cleaned with what you've suggested.
Aluminium rims are a lot softer and easily get stains, though they don't get the actual rust (mostly).
I've had similar stains on my Ford and was able to get rid of them after 2-3 iterations of Armour-All Wheel cleaner.
I think any decent off-the-shelf wheel cleaner should be able to help you. Although I don't believe it will be done in one go; you will need to repeat it a few times.
I've had very good results with Nevr-Dull - Magic Wadding Polish. It will take a bit more work to clean your wheels than CLR (or some other corrosive) but is probably safer for the wheels, and avoids the potential damage that steel wool might cause.
An Oxalic acid scrub is the old standard method of removing rust stains from chrome and other metal objects. It's sold as "wood bleach" in lumber yards, and likely sold as "rust remover" at hardware stores. My tin of the stuff is 20 years old, so I'm not familiar with what the brand names are today.
You could try using Cola and report back the results ... the Mythbusters didn't try Cola on Aluminum (which is what I am assuming your wheels are made of).
You should try using one of the 3M (or any other brand) recycled plastic bottle scrubbers. The aluminum should not be harmed as it is a much stronger material than thin woven plastic.
Mother's wheel polish has never failed me.
It works like a charm but use some elbow grease as well. I had little spots of surface rust on my chrome rims. My boyfriend used some clr 50/50 and it cleaned them wonderfully. They look brand new, yayyy for the boyfriend! He scored!
Don't polish your rims as they will get more dust and stains after that.
Use bathroom bleachers instead, If you do not trust this method, check it on a small area behind the rim, be carefull to not to touch the bleacher with your bare hand.
Bleachers do not chemically affect metals, as you may know they do not have a bad affect on bathroom equipment that mostly are coated with a thin layer of chrome.
Bleachers are the best solvant for brake pad stains that are very sticky.