Everyone is going to hate on this idea but as a vegan and a proponent of natural foods I try to find more natural solutions to these issues. This idea sounds weird but it works well.

Soak some Dates and Bananas or fruit of choice in water overnight or a few hours before your ride. The water left behind is tasty and full of carbs and electrolytes. It won't upset your stomach. Best part of it is you save the fruit after you soak it and it makes a great post-ride smoothie.

Either that or I use Vega Sport which continues to amaze me, but it's rather expensive.

One problem with gatorade is has way more sugar and sodium than is necessary. If I had to go with a more mainstream sports beverage I'd go with Clif Shot drink.