Lower revs can have many reasons, and might even be just a symptom of a "bigger problem". What you need is a proper revs/speed match, and to get the ball through its skid/hook/roll transition. Even with little speed you can score well when you get the basics right.
Buying aggressive balls must not be the solution. Do you long for revs or for hook (out of the box)? IMHO, using strong stuff might just make the problem more severe - you do not get much steam onto the ball, and you make it easy for your equipment to bleed that little energy it keeps when the lanes are too dry.
Some modern stuff promotes skid and a quick hook/roll transition, so it might be useful. But I'd rather check the basics like proper ball fit and your timing/release point and way of release in search for more speed or hitting power.
Maybe you release the ball too late or hang onto the ball - this kills revs, too, and you won't need a special drill to get this right. IMHO, consult a coach, because checking the "living" thing is more helpful than generic release tips here, which might be sound but not help you when you have something fundamentally fishy.
Good luck, that's a tough one!
DizzyFugu - Reporting from Germany
2010/11 Benrather BC Club Champion
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