Most people buy electric vehicles for convenience of life and work. When they choose electric vehicles, they can choose suitable for themselves, and fit themselves in performance requirements. For example, different use situations (weather, terrain, load, mileage...) can be selected for their own use.

1. The screw and nut of each fastening of electric vehicle shall be tightened, and shall not be loose or falling off. The rotating parts of electric vehicles shall be flexible in operation and rotation, and shall not be stuck or rigid. For example, the wheels before and after lifting shall be flexible and shall not have large left and right swings and up and down runout. When lifting the wheel to stop, the wheels shall be able to swing lightly and quickly before and after lifting the wheel, and shall not stop turning suddenly. The handlebars shall be flexible and free to rotate, the pedal shaft and crank shall be fastened, and they shall not be loose and flexible.

2. Electric vehicle transmission device: the gear change of the transmission vehicle shall be correct within the range of transmission, the shift position shall be clear and there shall be no neutral in the middle.

3. The electric vehicle chain should be loose and suitable and operate flexibly. Turn the crank sprocket repeatedly with the hand in the forward and reverse direction, and the chain can run flexibly without chain jumping and falling off.

4. Saddle parts of electric vehicles: hold the front and rear parts of saddle with both hands, press down the front end of saddle with one hand, and the front end of saddle shall not collapse. Turn the saddle horizontally with both hands, and the saddle shall not rotate.

5. Selection of electric vehicle brake and brake system: hold the handlebar with both hands, and push and pull the bicycle back and forth respectively, and the wheels should not rotate at this time; Release the handle and the brake system shall be able to reset quickly.

 6. Appearance of electric vehicle: the surface of all parts shall be clean, free of stain and corrosion, and the trademark decal shall be complete and clear without sharp edge burr, such as whether there is a scratch feeling on the edge of mud plate and chain cover, whether there is a scratch feeling at the end of steel rope such as brake, etc.

7. The brand or label of the parts observed by electric vehicles. Generally speaking, good parts are marked with obvious trademark marks and clear and exquisite designs.

8. The switch action of each part of electric vehicle is sensitive and reliable. The electric vehicle speed regulation is stable and reliable. Slowly turn the speed control handle, and the motor shall start smoothly with it, and accelerate without abnormal noise. After releasing the handle, the handle can be reset quickly and the motor decelerates evenly. The electric brake is fast and reliable when it is powered off. Turn the speed control handle, after the motor is running, after the brake is pressed, the motor can be cut off immediately. If there is power display, the voltage display can be seen to return to zero.