Symmetrical ball pluses.
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 The ball path is continuos through the pocket
 The ball may give you a little more hold because of later weight block stabilization.
 Less roll out

 When to use symmetrical balls
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 Good for dry back ends
 Good for higher rev players when they need a later reaction
 Good for lower & medium rev players on drier lanes

 Asymmetrical ball pluses
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 The ball gets into a roll faster when meeting friction
 A little more control because it has more roll than break on the backend

 When to use asymmetrical balls
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 Good for medium and lower rev players on oilier lanes because of faster roll
 Good for higher rev players when they need more control
 Good for all bowlers when then midlanes have less friction

As a side note: pls. remember that the force of the core's mass bias is the relevant reaction factor, not the simple fact that it has an asymmetrical shape! There are many asymmetrical cores out there, but they have only a low mass bias rating, due to the inner weight distribution. You can even achieve a symmetrically looking core with a strong mass bias through different material densities - better check for the RG asym. diff. numbers to be sure what you have at hand.
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DizzyFugu - Reporting from Germany

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