[Hugh]

Mix laundry bleach 50/50 with distilled water. Lay the grip on a flat surface in the sun and drop some of the bleach solution on the black spot. You may have to repeat several times depending on how fast it evaporates.

You can also bleach the whole grip by putting some of the solution in a shallow pan and soaking the grip in it in the sunlight. Takes 30" to an hour to bleach out good, depending on the strength of the sunlight.