How I cleaned both the tanks on my 1978 Harley FXS Lowrider Shovelhead at home with White Vinegar( not to harsh, but strong enough to do the cleaning), some chain & bolts( to knock loose the crusty stuff), distilled water & Baking Soda(to neutralize the acid from the Vinegar). The results were very good. Hope this helps anyone out there wanting to do this at home themselves!!