Like any other pearl: when the scratches start to make the ball too early reacting, then add a dose of polish.
There is no set number of games because it depends on several fatcors that vary wildly: rev rate, amount of oil protecting the lane, age and condition of the lanes, whether they are synthetic or wood.
The number of games could be as low as 15 for a high rev player bowling on real old wooden lanes or it could be 50 - 75 games for a low rev player on well kept, new synthetic lanes.
You have to keep an eye on the track for wear and tear and another eye on the ball reaction AND understand when the early reaction is due to wear on the ball or due to less oil being used on the lanes.
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"None are so blind as those who will not see." Unofficial Ballreviews.com FAQEdited on 8/24/2008 5:06 PM