Complex carbs. Cycling is a fast twitch lactic acid exercise. You need carbs to augment power output. There was a physics study done on Tour de France cyclists: Showed that the wattage generated by cyclists is low, 60 watts per day, rest is heat. Cycling is highly inefficient. You need energy with water added. Back when I was cycling lots, I really liked Twinlabs Carbo fuel. It had lots of cofactors plus the complex carbs that increased my nutrient intake and delayed fatigue, I highly recommend it if it is still made. It takes good too. I would stay far away from pseudoephedrine. It hasnt clearly demonstrated in studies that it augmented power output on a cycle ergometer test and it affects the dopaminergic system. Caffeine is fine, highly recommended and safe are yerba mate and green tea.