Preheat grill to medium high. Peel squash and cut in half lengthwise. Scoop out and discard seeds and pulp. Cut into chunks. Add squash, olive oil, cinnamon, nutmeg, ginger, cloves, and salt to a bowl. Toss until squash is well-coated. Place in a grill basket.
Grill squash 30 minutes, stirring every 5 minutes or so. Squash is done when largest pieces are tender when pierced with a fork. Final cook time will vary depending on size of pieces.
Remove from grill basket and add to a serving bowl. Drizzle with maple syrup, if using, and sprinkle with pecans.