How much effort can you save by breaking wind on a bicycle

15-20 percent. The wind-breaking effect of bicycling is related to riding speed, weight, height, and the design of the car, and can help save 15-20% of force. "Breaking wind" refers to the fact that when a bicycle, for example, is running, the space behind the rear end becomes part of the weak drag space due to the compression of the air in front of it, the friction of the surfaces against the air on both sides, and the space behind the rear end.