Like our FB page

Like our website
Tweet @bowlingball
Follow @bowlingball
Use and distribution of this article is subject to our terms and conditions
whereby's information and copyright must be included.

Why Use A Bowling Ball Balance Hole, Originally Posted: 5/7/12; Updated: 4/13/21

**2021 Update: Per USBC Official Rules, balance holes in bowling balls are now considered illegal and must be plugged in order to be used in USBC sanctioned events. For more info, please click here. **

If you are wondering why use a bowling ball balance hole, the reasons are simple and scientifically sound. The balance hole is an extra hole (balance hole or weight hole) in a ball which is used to establish static balance as per the guidelines of United State Bowling Congress (USBC) specifications. Pro shop professionals will answer the question why use a bowling ball balance hole when addressing the challenge to create dynamic influence on the bowling ball motion. The effect of static weights is extremely minimal but the non-gripping balance hole alters the ball's dynamics which are those forces affecting the ball when it is in motion.

The location of a balance hole with regard to the distance from the pin in a bowling ball is the primary tool for altering the core dynamics. The strength of the core is measured by the difference of the RG of the height of the core and the RG of the width of the core. This relationship is referred to generally as Differential of RG. The maximum allowable diameter is of a balance hole 1-1/4" for USBC sanctioned play.

The greater the difference between the height and the width of the core, the higher the Differential. Higher Differential results in more track flare potential and will induce the ball to release energy quicker when the ball encounters friction. The greater the flare potential, the greater the hook potential and the ball motion will be reflected with a noticeable increase in the angle of entry into the pocket.

The USBC states that a bowling ball may have no more than one (1) ounce of side weight after the holes are drilled. You need a DoDo scale to weigh the ball for side weight. If you are over one (1) ounce (we recommend 3/4 ounce) then use the guide provided in bowling ball weight hole removal chart located at our site to help determine what size drill bit you should use, and how deep you should drill.

It helps to know some of the information and specifications pro shop professionals use so you gain greater insight into the net affect balance holes have influencing bowling ball motion. This bowling ball weight hole removal chart provided courtesy of assists the pro shop professionals in determining the size and depth of a balance hole to remove a given amount of weight and the size of a drill bit to accomplish the task.

Drilling a balance hole in your bowling ball will change the Differential ratio when the ball is in motion. Since the Differential ratio will influence the ball motion, you can control the degree of transition your ball makes as it travels through the mid-lane and when it transitions at the break point down the lane. The larger the differential ratio, the more asymmetrical the bowling ball. Conversely, the smaller the differential ratio, the less asymmetrical the ball.

Varying degrees of longer transitioning (longer hook zone) ball motion can be obtained by choosing to drill an asymmetrical ball. Asymmetrical balls after drilling show a defined, angular motion. These balls can create more area at the break point and will respond to friction faster at the break point than symmetrical balls.

Often experienced bowlers will drill a ball and then add a weight hole to alter the dynamics of the ball while it is in motion. Ball motion control is the objective of any experienced bowler looking to create a consistent ball reaction on given lane conditions. Use of the balance hole is one tool to help achieve bowling ball motion control.

We hope this information helps you in understanding the purpose of a bowling ball balance hole and how it can affect ball motion. We recommend you consult your local pro shop professional when selecting a new bowling ball and a drilling layout and to determine if a balance hole will improve your ball motion. has become the No. 1 “e-tailer” of choice for bowling equipment by consumers of America. When you are ready to place an order, it is an easy process by following simple online instructions. Thanks for visiting

Click here to shop smart deals Need Help? Click here to access our contact information. Click here to shop 3G Tour X Shoes!
WeeklyContestText Click here to shop all Pyramid bowling bags