Which adjustment is NOT typically made to enhance a motorcycle's torque?

Reducing engine displacement is not a typical adjustment made to enhance a motorcycle's torque. In fact, reducing the size of the engine usually leads to a decrease in torque, as torque is generally proportional to the engine's displacement. Larger engine displacements allow for more air and fuel to be combusted, resulting in greater torque output.

On the other hand, increasing torque can be achieved through adjustments like installing a larger rear sprocket, which alters the gear ratio, providing more torque to the wheels at the cost of top speed. Optimizing the fuel mixture ensures that the engine burns the right amount of fuel for efficiency and power, which can improve torque delivery. Improving exhaust flow enhances the engine's ability to expel exhaust gases and take in fresh air, leading to better combustion efficiency and increased torque.