I've used simple green in water to soak balls and it works well. There are directions on the bottle that tell you how much water to mix in depending on how concentrated you want the stuff. It cuts through grime and oil fairly well, but nothing works as well as normal ball cleaner. Track's Clean & Dull takes off belt marks and grime better than anything that I've seen/used. However, using a pumice-based cleaner like Go-Jo or Fast Orange works well also. You have to be careful however, because that stuff is abraisive and will alter the coverstock finish like a scotchbrite if you scrub too hard. Trial and error is what you need. As long as you're not baking or blow-drying balls, nothing you do should hurt them that bad. Good luck.
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I can't bowl 300, but I can bench 310 : )