Hmmm I always wondered what the most used bike was. A mountain bike or a city bike, a road bike or a cruiser?… Mountain bikes are the most widely used bicycle type. It was designed for traversing forests and rougher or mountainous terrains. Its construction differs from a typical bicycle in many ways. The most noticeable of these differences are the inclusion of suspension on the frame and fork, larger knobby tires, more durable heavy-duty wheels, more powerful brakes, and lower gear ratios, which are needed for steep gradients and better traction.