I generally wait close to a day, or at least over night just to be safe.  You probably only need 4-6 hours just to make sure the ball is the same temp from the core to the shell.

White streaks?  I have had this happen to a couple of my bowling balls, but I have done dozens and only a couple have had this happen.  Not sure why, but I think it has something to do with the heat.  It does not seem to effect the balls negatively, just a cosmetic change in mine.  Actually makes it easier to find mine on the return.
 

I had a Shock & Awe turning from Salmon/Sky Blue to Sand/Purplish-Grey after a hot water bath. I was shocked, but the ball was definitively clean thereafter (*squeak*), behaved as usual, and the colors came back after some use and probably lane conditioner absorption. My personal theory is that the colors "bleach out" because the porous coverstock material is "emptied" from anything, be it oil or plasticizer.

 

Anyway, I agree that a ball should be left alone for a while after a hot water treatment, and I'd also make sure that it rests in a ball cup or somewhere, where its weight is distributed on a larger footprint in order to avoid tensions between cover, filler and core due to temperature changes.

DizzyFugu - Reporting from Germany
2010/11 Benrather BC Club Champion
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