I often use spray-on WD-40 a lot as a cleaner. It thins grease down to an oil-like consistency that is easy to wipe away.
I bought a very low-cost Sugino Super Maxy crankset that was black/grey and it seemed impervious to any cleaners or polishes that I tried, even with extensive and persistent rubbing. I am not sure what type of aluminum it used. So, I sacrificed the anodizing with the weakest sandpaper+oil that I have, which is normally 1500 or 2000 grit plus WD-40 to wetsand the part.
- Don Gillies
San Diego, CA, USA