Why are mid-mounted motors commonly used in high-speed electric motorcycles? But rarely use hub moto

Mid-mounted motors are commonly used in high-speed electric motorcycles due to several key advantages they offer:

1. Weight Distribution: Placing the motor in the middle of the motorcycle helps achieve a more balanced weight distribution between the front and rear wheels. This improves stability and handling, especially at high speeds. By having the motor near the center of the motorcycle, the overall weight is more evenly distributed, resulting in better control and maneuverability.

2. Handling and Agility: The positioning of a mid-mounted motor lowers the center of gravity of the motorcycle. This lower center of gravity improves the motorcycle's handling and agility, making it easier to navigate corners and maintain stability during rapid maneuvers. The improved balance enhances the overall riding experience, particularly at higher speeds.

3. Thermal Management: Electric motors generate heat during operation, and mid-mounted motors have better opportunities for effective thermal management. Placing the motor in the middle allows for improved airflow around the motor, facilitating better cooling. Cooling systems such as fans or heat sinks can be installed more easily in this configuration, ensuring efficient heat dissipation and preventing overheating.

4. Power Transfer Efficiency: Mid-mounted motors typically use chain or belt drive systems to transfer power from the motor to the rear wheel. This setup allows for optimized power transfer efficiency and the ability to adjust gear ratios. The flexibility in gear ratios enables high-speed electric motorcycles to deliver optimal performance across different riding conditions, including acceleration and top speed.

In contrast, hub motors are rarely used in high-speed electric motorcycles due to a few limitations:

1. Weight Distribution: Hub motors are integrated directly into the wheels, resulting in a concentration of weight in the wheel hubs. This can negatively impact weight distribution and overall balance, potentially affecting the motorcycle's stability and handling, particularly at high speeds.

2. Unsprung Mass: Hub motors contribute to the unsprung mass of the motorcycle, which refers to the weight not supported by the suspension system. Higher unsprung mass can reduce the motorcycle's ability to maintain traction, handle bumps, and provide a smooth ride.

3. Cooling Challenges: Hub motors are more challenging to cool efficiently compared to mid-mounted motors. Their location within the wheel makes it difficult to dissipate heat effectively, potentially leading to overheating issues and decreased performance.

4. Limited Gear Options: Hub motors typically have a fixed gear ratio, limiting the motorcycle's performance capabilities, especially in terms of acceleration and top speed. In contrast, mid-mounted motors with chain or belt drives offer greater flexibility in adjusting gear ratios to suit different riding conditions and optimize performance.

While hub motors have their advantages in certain applications, such as electric bicycles or low-speed electric motorcycles, mid-mounted motors are generally preferred for high-speed electric motorcycles due to their superior weight distribution, handling characteristics, thermal management, and power transfer capabilities.