Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 10 inch tube pan.
In a large bowl, mix together the flour, sugar, baking soda, cinnamon and salt. Make a well in the center and pour in the eggs, oil, bananas and pineapple. Mix well and pour into prepared pan.
Bake in the preheated oven for 70 to 80 minutes, or until a toothpick inserted into the center of the cake comes out clean. Let cool in pan for 10 minutes, then turn out onto a wire rack and cool completely.