The ATV gear is mainly designed to transmit power and achieve the driving function of the vehicle. Specific to reverse gear and forward gear, although their physical structure may be similar, but their working principle and use are very different.

1. Gear meshing mode: whether it is reverse gear or forward gear, their tooth shape is designed according to the gear meshing principle. When the gears rotate, their tooth tips mesh with each other, which transmits torque and rotational motion. However, reverse and forward gears may be meshed differently to suit their respective work needs.

2. Gear arrangement: gear arrangement is directly related to the driving performance of the vehicle. In the transmission, multiple gears are arranged in a certain order to achieve different transmission ratios and speeds. Reverse gear and forward gear are usually arranged differently to ensure that the vehicle can complete the reverse and forward operation smoothly.

3. Output shaft speed direction: This is the obvious difference between reverse and forward gear. Under the same input shaft speed, the output shaft speed direction of reverse gear is opposite to that of forward gear. This means that when the vehicle is in reverse, its rear wheels (or drive wheels) rotate backwards, causing the vehicle to travel forward.

4. Material and hardness of the gear: Because the gear will withstand large torque and wear during use, they are usually made of materials with certain strength and wear resistance, such as alloy steel. In addition, in order to improve the service life of the gears, they also need to be properly hardened.

In short, while reverse gear and forward gear may be similar in physical construction, their design and purpose are very different. These differences allow them to play their respective roles on ATVs, ensuring that the vehicle can flexibly respond to a variety of driving conditions.