Stumbled across this on Facebook...

https://www.change.org/p/united-states-bowling-recertify-the-jackal-and-jackal-carnage-for-usbc-play

>>  they could have just told them to cease production, grandfathered the old stuff in, and there would have been no issue.

There would be an issue. You now set a new precedent. I send in a ball to USBC to get approved knowing the differential is .057. Once I am approved I change the core so the differential goes to .063. People buy my ball and love the hook on heavy oil. USBC comes back six months later and says we have to have to stop production. Your ball is no longer legal. However, now the USBC has to grandfather my previously made ball, too.

Every manufacturer would do this since they would not have to replace any bowling ball previously sold. Plus, maybe they never get caught and just get to keep making these bad bowling balls. I honestly believe 100% that the USBC did the correct thing here.

And yes, between my son and I we have 3 Jackals. So no, I'm not saying this from an outsiders perspective.

I do not think that any manufacturer would change the core once there is approval because then you have a different ball.  I believe that this whole thing with Motiv is truly them not understanding their own manufacturing tolerances.  I have been an engineer in the manufacturing industry and understanding your manufacturability tolerances is essential.  It has been said on other posts that a common tolerance for differential is +/-.004 so making a ball to send to USBC for approval at .060 is just asking for trouble.  This is the very reason you don't see other balls out there with the claim that they are at a .060 differential.  I have many customers that have bought these balls in question and I am hoping that this comes to a quick resolution.  I also believe that USBC needs to stick to the findings as all balls, no matter the manufacturer, are tested in the same manner.  It is a manner that is accepted in the industry.  USBC and all the ball manufacturers use this method as far as I know.  Until there is a better method this is it.  Get over it and move on.  Motiv will move on as well.  I am sure they are just looking for ways to lessen the cost.  I don't believe this will put them out of business but they will most likely need to tighten the belt a bit on spending.  In the end the consumer always gets the short end of the stick.
BTW, I deal with measurements in down to the .xxxx all the time.  When you do that the number does not seem as small as you think.