Howdy Since there are many references to Muriatic acid, etc.. for help cleaning and identifying the piston material out of the bore, I thought I would add my.02 after seizing the piston in my Jonny 920 yesterday. ( Totally my fault, no, I did not lean seize it, Much more exotic than that) Anyway, I used the above product for cleaning my V-Rod wheels when I first bought it on recomendation from a trucker. Nothing else worked 1/2 as good. The stuff is amazing. Ammonium Bifluoride, Phosphoric acid, etc... Won't bother the chrome cylinders like muriatic. Foams like crazy on ANY aluminum. If there is any present, you know it. I have used muriatic in the past, and I will never use it again after trying this stuff. Have a good one, D.