I'll let my ball sit out in the sun on a hot day, 80-90. Rotate it and then wipe all the oil off and then bring it inside (away from the A/C). After it cools off a little I'll rub it with alcohol, it does get the belt marks off and cleans it up. Keep in mind I don't do this on a regular basis, cleaning your ball too much with Isopropyl can actually hurt your ball. Oh and don't clean it with anything above 70%
"Bowling is like sex...it's only fun if you're doing it"