There's a product called M.A.A.S. that I picked up at wallyworld in the household cleaning section (where you find windex and pine-sol). Man this stuff is amazing!

There must have been at least 2 years worth of "gunk" and exhaust soot on the chrome tips of my 8 and I didn't think this stuff would work as well as it did.

Just squeeze some on a micro-fiber cloth, rub onto the chrome, and immediately wipe away with a clean cloth. Years of caked-on black soot and oxidation disappeared like magic, and that chrome finish looks like new (I can see my reflection)! I didn't even have to apply very much pressure... only as much as wiping down a dirty window.

The tube cost about $3-$4... It's concentrated and only needs a small amount to do an awesome job! Go get some and clean those dirty tips!

 

I have used this product for cleaning old brass and rusty knife blades. The quantity is small (small toothpaste tube, or like a tube of hydrocortisone).

A large bottle of Brite Boy is more economical long-term, I think.