Dissolve yeast in warm water. Add honey, and stir well. Mix in whole wheat flour, salt, and vegetable oil. Work all-purpose flour in gradually. Turn dough out onto a lightly floured surface, and knead for at least 10 to 15 minutes. When dough is smooth and elastic, place it in a well oiled bowl. Turn it several times in the bowl to coat the surface of the dough, and cover with a damp cloth. Let rise in a warm place until doubled in bulk, about 45 minutes.Punch down the dough. Shape into two loaves, and place into two well greased 9 x 5 inch loaf pans. Allow to rise until dough is 1 to 1 1/2 inches above pans.Bake at 375 degrees F (190 degrees C) for 25 to 30 minutes.