If her ball speed is very high with 12lb, then go to 14lb. If not, move up to 13lb first. If she can last 3-4 games with 13lbs no problem, then 14lb could be the answer in the future. My wife has an old 12lb Gyro that she throws about 17mph down the middle. I am drilling her a 14lb tornado this week, cause she leaves more 5 pins than anybody due to deflection. This will also slow her ball speed down and get a little more consistency in her swing instead of just throwing it down the middle.
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