Everything is relative Einstein said, and it is the same about bowling balls. I cannot say if there is a general life span to a ball, but taking care of it should induce longevity.
Keep it clean. Wiping with a towel after each frame prevents oil and other, uglier things form being sucked up, which keeps up performance. Every now and then, clean the surface e.g. with a mild cleaner. If it is a sanded ball and loses performance, a 3M pad will scuff it back to life. If you see a visible track on a polished one, consider some new polish or a trip in a spinner. There are several surface care products available.
Another option ("big service") is a de-oiling procedure, which will restore performance. You can either have it done at a pro shop for a fee, or try it yourself at home, either in the oven at low temperature (oil etc. will ooze out. Wipe off, repeat several times and avoid temperature shocks or the ball might crack!), or put the ball in a bucket with warm/hot water, which might be the more carful option.
If anything else fails or it has caught major bruises which hamper performance, a ball can be resurfaced several times at the pro shop. But if this option is used up, the ball is finally "dead".
Additionally, taking care of your equipment will also keep up its life. Do not have balls bump around, e.g. in the back of your car (if you have one), and do not expose them to harsh temperature conditions or changes (e.g. leaving them over night in a winter car trunk, or keep them in hot summer sun).
That in mind, a ball will last quite a while.
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DizzyFugu --- Reporting from Germany
"All that we see or seem, is but a dream within a dream..." - Edgar Allen Poe
Edited on 1/25/2005 10:28 AM