Where to start...
I hate racism and I hate that it is present in our fraternity. It shouldn't be, and any man who follows our tenants would immediately abandon such thoughts. But, that's not how it is.
If you forced me to answer yes or no as to whether this amendment violates any of the tenants of Masonry, I'd have to say no. As has been stated, we are not to judge based on the external, so this isn't really a change to our principles.
However, I think this is a very slippery slope regarding forcing people to possibly vote against their beliefs. We might disagree with their beliefs, but free will is, in my opinion, the single greatest gift given to us by our creator, and forcing someone, or bullying them into, voting in a way that is against their opinions, provided it isn't expressly prohibited by our rituals, is wrong. So, in summary, while I don't disagree with THIS amendment, I think it sets the stage for other problems.
In addition, there is the issue of conflicting ideas. We are not to base our votes on the external, and yet, we are also taught to retain the peace and harmony within the lodge. While in a perfect world, these would not conflict, in reality, they sometimes do. A black man coming into a lodge with a racist would create disharmony.
I can already hear you all mashing your keyboards and screaming "THEN THE RACIST SHOULD LEAVE!". Well, maybe so, but it's still disharmony. So, you're saying that this racist brother, someone your lodge welcomed into rolls, and who may have given decades of service to his lodge, should leave to make room for someone that the majority of the lodge has never met? Again, it's a slippery slope.
I would argue that there's a far simpler way (albeit not as fast) to fix this problem; quit admitting racists! Everyone is talking about how the black ball is so powerful for keeping black men out. It is equally as powerful in keeping racists out. This isn't rocket science. A man petitions your lodge, you pull him aside and say to him "as a brother of this lodge, I don't feel that racism has any place here. That being said, if you were to become a member, would the color of a man's skin influence your opinion of him?" If he says yes, use that black ball. It might take decades, and it might result in no new brothers being made if you have to drop a black ball and every candidate, and the lodge may die. But so what? Guard the west gate. Keep the racists out. After all, isn't it more important to rid the Craft of racism rather than to find a way to work around them?