Dry Lane Conditions
Dry lane conditions are most commonly found in older bowling centers that haven&'t converted to synthetic lanes. Lanes that are oiled to help facilitate ball movement will also experience dry conditions as the oil evaporates due to increased temperatures or is worn away with use. When facing these conditions, a player should opt for a polished ball—the smoother, the better. A slick ball will act as its own curving agent on a dry surface, providing adequate hook to hit the center of the pins without requiring any oil. Many pro bowlers will wipe their ball with a dry towel prior to the throw to ensure it is as slick as possible.
Oily Lane Conditions
Oily lane conditions are trickier to navigate. Regular synthetic lanes will always offer a certain amount of slickness, making them more consistent with regard to speed and amount of hook. Heavily oiled lanes offer less consistency because the oil will dry up or wear away over the course of a day. A rough, dry ball works best on a slick lane. The ball essentially lets the lane do all the work; a well thrown hook shot will "catch" the oil about halfway down and curve toward the middle. Smoother bowling balls perform poorly on these conditions; because both surfaces are slippery, the ball doesn&'t "catch" properly, skidding out and missing the middle altogether.
Spare Balls
Regardless of the lane condition, it is always a good idea to have a ball for converting one-pin spares. Expert bowlers don&'t get fancy when it comes to making a spare, which is why they opt for a straight shot over their normal curve throw. With a straight toss, a bowler is not left at the mercy of shifting lane conditions that may cause the ball to over-hook, under-hook or spin out completely. For a single-pin spare or a conversion involving two or more pins bunched together, a heavy ball is the right choice. A well-placed shot with a heavier ball will wipe out larger groups of pins with ease. A heavier ball will also travel straighter. Multi-pin "split" spares—where the pins are further apart—should be attempted with a regular ball, since a hook is the only way to generate the necessary pin action to complete the spare.