It's not terribly racist, and he wouldn't be offended if he knew.

"Oh, uh. I can...well. My people, where I come from, we can change into other things. Vehicles, mostly, sometimes animals. And my friend Rewind turned into a giant memory stick, can you imagine? Then there's mono-formers, but now I'm getting off the subject and I don't much like to talk politics. Anyway. Alt-mode. Alternate. So...like I am now? That's Robot-mode. That's basically the default. But see, we can also do this..."

He stands and moves a little bit away before transforming into a small vehicle with to large exhaust pipes. "See? Alt-mode!"