Martin Luther King most certainly was racist.
The mistake you are making is that you think labeling something 'racist' is the same as labeling it 'evil'. As an example : Black only scholarships, which Emon argues were created in response to racist bias. Are these scholarships racist? Yes. Are they evil? No.
Martin Luther King was racist because he was human, and a preference for your own kind is a normal human tendency. Martin Luther King's ideals were very non racist. MLK sought to remove race from the table entirely. He did not want a black man to get a job because he was black; he recognized that things like affirmative action were inherently racist.
You (All of you) are incapable of discussing the issue because you can not put aside what society has trained you to believe; that it's okay for some segment of the population to use a word but not okay for others; that WE have to pay for the sins of our fathers; that we must notice the color of a person's skin or risk being sued for discrimination or arrested for a hate crime; that the same act, when directed at two people of a different race, is worse depending on the color of the victim's skin.
Society has taught you that racism is okay, so long as it's a certain kind of racism; and it's taught you that racism is the greatest evil in the world, that it is unnatural, that anyone who speaks out against the kind of racism society deems acceptable is racist and evil, and worthy of your scorn, when they are the least racist of all.