A Pro Pin bowling ball from SPI Bowling Products (Storm, Roto Grip, and 900 Global) is where the Pin (Core Top) distance from the CG (Center of Gravity) is 6 - 6 1/2" out. Anything more than 6 1/2" would be considered an X-Blem.
This is a premium, first-quality ball crafted to the same exacting standards as the rest of these elite lines - ensuring top-tier performance and durability without any compromises.
Due to changes in the USBC rules for static balances and weight holes, Pro Pins/Pro Cg's no longer have specialized and unique layouts. These balls can be drilled using any of the SPI drilling layouts. NOTE - On Pro CG balls, the final placement of the CG (Center of Gravity) will appear to be in an odd location but this will not affect the ball reaction.
The Viking is the go-to option for tackling patterns after they transition. The RB 90 Hybrid coverstock is engineered to deliver a balanced motion — blending solid traction with the clean responsiveness of a pearl. Its hybrid nature ensures reliable midlane read without sacrificing backend pop. Featuring a higher RG, the Strobe A.I. Core’s single-density design enhances control through the midlane while still creating a powerful and continuous backend motion.
Here's what 900 Global has to say about the Viking:
The Viking will be the clear choice to combat patterns once they have gone through transition. RB 90 Hybrid was designed specifically to bring balanced reaction. The solid component of the cover will give you the proper amount of traction while the pearl aspects will optimize responsiveness. With a raised RG, the Strobe A.I. Core's single density weight block uniquely reads the midlane while still providing a very strong backend shape.
