What is the reason why the brake of the tricycle is hard to press and cannot stop?

[DelMaverick]

When pressing the oil brake, you should feel pressure in your hand. Also, check for any signs of oil leakage. If neither of these is the issue, there might still be air in the brake lines, which needs to be bled. Tricycle driving precautions: Speed requirements: Due to the compact size of electric tricycles, their driving speed is relatively slow. Driving too fast can easily cause the vehicle to drift, making it difficult to control. Generally, the speed of an electric tricycle can reach 40-45 km/h, but for safety reasons, the recommended speed should not exceed 20 km/h. Load requirements: For household electric tricycles, the load capacity is relatively light, usually around 200 kg. For cargo-type electric tricycles, the load capacity is generally 300-600 kg. Due to higher requirements for the motor, battery, and welding process, cargo-type tricycles have a relatively larger load capacity, which can reach 1-3 tons.