Preheat the grill to medium. Rub the grill with some vegetable oil and place the corn in the husks on the grill with the ends facing out. Turn the corn as each side chars, for a total grilling time of about 15 minutes. Remove corn from the grill and allow to rest a minute or two, then remove the husks. Allow to cool just until you can hold it without burning your fingers. Scrape the kernels off into the Bundt pan, then transfer to a large serving bowl.
Toss with the black beans, tomatoes, bell pepper, and onions. Add about 1/4 teaspoon sea salt, or more to taste, and stir. Grind a little fresh pepper on top, and squeeze the lime over all the salad. Serve at room temperature or chilled.
Removing corn kernels from the cob can be a messy experience with kernels flying everywhere, but a Bundt pan can help with that. Just hold the wide end of the cob and place the tip in the hole of the Bundt pan, then use a sharp knife to scrape off the kernels. A paper towel placed over the hole will help protect the nonstick surface.